source
sequence | text
stringlengths 99
98.5k
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|---|---|
[
"stackoverflow",
"0016345974.txt"
] | Q:
Displaying digits in forward direction in C?
I'm trying to make a program that takes an inputted integer and reads the digits forwards. So 12345 would be...
Digit: 1
Digit: 2
Digit: 3
Digit: 4
Last Digit: 5
Inputs with trailing zeros (like 100000) run into problems though. In the forward direction, some of these zeros show up as 9's and the last integer does not show up as 'Last Digit:'. Any ideas?
#include <stdio.h>
#include <math.h>
int main(){
int n = 0;
int i = 0;
int j = 0;
int k = 0;
int output2 = 0;
int count = 0;
printf("Number? > ");
scanf("%d", &n);
i = n;
j = n;
while (i){
i = i/10;
count++;
}
printf("Foward direction \n");
while (count > 0){
k = j;
k /= pow(10, count - 1);
output2 = k % 10;
if (output2 >= pow(10, count - 1)){
printf("Last digit: %d \n", output2);
}
else {
printf("Digit: %d \n", output2);
}
count -= 1;
}
return 0;
}
A:
If you want to be clever, simple and elegant, you can always use recursion.
void print_digits(int n)
{
if (n >= 10) {
print_digits(n / 10);
}
putc('0' + n % 10, stdout);
}
In your code, pow() is erroneous - don't try to use floating-point numbers to solve problems about integer numbers.
Edit: here's the full homework done for OP, just so that @darron will be happy as well:
void print_digits(int n, int islast)
{
if (n >= 10) {
print_digits(n / 10, 0);
}
if (islast) {
printf("Last ");
}
printf("Digit: %d\n", n % 10);
}
Call with the islast argument initially being true (nonzero):
print_digits(12345, 1);
this produces
Digit: 1
Digit: 2
Digit: 3
Digit: 4
Last Digit: 5
as output.
|
[
"tex.stackexchange",
"0000285866.txt"
] | Q:
Load PDF metadata from an external file
I see here that it's nice to put the entire \hypersetup command in an external .tex file. In my case, only a snippet is required, which has been generated by an external program and will change frequently, say, a build number. But this doesn't work:
\documentclass{article}
\usepackage{hyperref}
\hypersetup{pdfsubject=\input{buildno.txt}} % other info omitted
\begin{document}
Thanks
\end{document}
The generated PDF will have a subject "buildno.txt" rather than the text file's content. Is there a convenience way to load such information without scripting the entire \hypersetup command in the external file?
A:
You could modify the external file to define the subject as a command, then input the file and use the command; for example:
\begin{filecontents*}{buildnodef.txt}
\def\buildno{version 6}
\end{filecontents*}
\documentclass{article}
\input{buildnodef.txt}
\usepackage{hyperref}
\hypersetup{pdfsubject=\buildno} % other info omitted
\begin{document}
Thanks
\end{document}
Alternatively, you could read the contents of the file to a command, which may then be used. Using, for example, the catchfile package:
\begin{filecontents*}{buildno.txt}
version 7
\end{filecontents*}
\documentclass{article}
\usepackage{catchfile}
\CatchFileDef{\buildno}{buildno.txt}{}
\usepackage{hyperref}
\hypersetup{pdfsubject=\buildno} % other info omitted
\begin{document}
Thanks
\end{document}
|
[
"stackoverflow",
"0032899386.txt"
] | Q:
Problems with classes / methods
So I have this code I'm working on for my AP computer science class and I'm getting tons of errors when I compile even though when I look at it, it looks fine and everything is in order. All the errors are coming from my myClock class and RepairShop class.
public class APCS_104_Time {
public static void main(String[] args) {
tester tester = new tester();
}
}
class myClock {
private int minute;
private int hour;
public myClock() {
hour = 2;
minute = 3;
}
public myClock(int minute, int hour) {
public int getHour() {
hour = IO.getInt("Enter the hour");
return hour;
}
public int getMinute() {
minute = IO.getInt("Enter the minute");
return minute;
}
public void int setMinute(int minute) {
this.minute = minute;
}
public void int setHour(int hour) {
this.hour = hour;
}
public String toString() {
if (minute < 10) {
return (hour + ":0" + minute);
}
else {
return (hour + ":" + minute);
}
}
}
}
class RepairShop {
public void int springForward(myClock time) {
hour++;
}
public void int resetClock(myClock time) {
hour = 2;
minute = 3;
}
public int cloneClock(myClock time) {
myClock copy = myClock myClock.clone();
return myClock;
}
}
class Tester {
Tester() {
myClock time = new myClock();
System.out.printf("The time is: " + myClock(2, 20));
}
}
Error messages include:
C:\Users\Tom\Dropbox\Auriemma, Thomas\AP Comp Sci\Unit 1\APCS_104_Time.java:38: error: illegal start of expression
public void int setMinute(int minute) {
^
C:\Users\Tom\Dropbox\Auriemma, Thomas\AP Comp Sci\Unit 1\APCS_104_Time.java:38: error: illegal start of expression
public void int setMinute(int minute) {
^
C:\Users\Tom\Dropbox\Auriemma, Thomas\AP Comp Sci\Unit 1\APCS_104_Time.java:38: error: ';' expected
public void int setMinute(int minute) {
^
C:\Users\Tom\Dropbox\Auriemma, Thomas\AP Comp Sci\Unit 1\APCS_104_Time.java:38: error: '.class' expected
public void int setMinute(int minute) {
^
C:\Users\Tom\Dropbox\Auriemma, Thomas\AP Comp Sci\Unit 1\APCS_104_Time.java:38: error: ';' expected
public void int setMinute(int minute) {
^
C:\Users\Tom\Dropbox\Auriemma, Thomas\AP Comp Sci\Unit 1\APCS_104_Time.java:42: error: illegal start of expression
public void int setHour(int hour) {
^
C:\Users\Tom\Dropbox\Auriemma, Thomas\AP Comp Sci\Unit 1\APCS_104_Time.java:42: error: illegal start of expression
public void int setHour(int hour) {
^
C:\Users\Tom\Dropbox\Auriemma, Thomas\AP Comp Sci\Unit 1\APCS_104_Time.java:42: error: ';' expected
public void int setHour(int hour) {
^
C:\Users\Tom\Dropbox\Auriemma, Thomas\AP Comp Sci\Unit 1\APCS_104_Time.java:42: error: '.class' expected
public void int setHour(int hour) {
^
C:\Users\Tom\Dropbox\Auriemma, Thomas\AP Comp Sci\Unit 1\APCS_104_Time.java:42: error: ';' expected
public void int setHour(int hour) {
^
C:\Users\Tom\Dropbox\Auriemma, Thomas\AP Comp Sci\Unit 1\APCS_104_Time.java:46: error: illegal start of expression
public String toString() {
^
C:\Users\Tom\Dropbox\Auriemma, Thomas\AP Comp Sci\Unit 1\APCS_104_Time.java:46: error: ';' expected
public String toString() {
^
C:\Users\Tom\Dropbox\Auriemma, Thomas\AP Comp Sci\Unit 1\APCS_104_Time.java:58: error: <identifier> expected
public void int springForward(myClock time) {
^
C:\Users\Tom\Dropbox\Auriemma, Thomas\AP Comp Sci\Unit 1\APCS_104_Time.java:58: error: '(' expected
public void int springForward(myClock time) {
^
C:\Users\Tom\Dropbox\Auriemma, Thomas\AP Comp Sci\Unit 1\APCS_104_Time.java:58: error: invalid method declaration; return type required
public void int springForward(myClock time) {
^
C:\Users\Tom\Dropbox\Auriemma, Thomas\AP Comp Sci\Unit 1\APCS_104_Time.java:62: error: <identifier> expected
public void int resetClock(myClock time) {
^
C:\Users\Tom\Dropbox\Auriemma, Thomas\AP Comp Sci\Unit 1\APCS_104_Time.java:62: error: '(' expected
public void int resetClock(myClock time) {
^
C:\Users\Tom\Dropbox\Auriemma, Thomas\AP Comp Sci\Unit 1\APCS_104_Time.java:62: error: invalid method declaration; return type required
public void int resetClock(myClock time) {
^
C:\Users\Tom\Dropbox\Auriemma, Thomas\AP Comp Sci\Unit 1\APCS_104_Time.java:69: error: ';' expected
myClock copy = myClock myClock.clone();
A:
There are many things you need to fix:
First of all
//This myClock constructor can't contain other method!
public myClock(int minute, int hour) {
public int getHour() {
hour = IO.getInt("Enter the hour");
return hour;
}
...
}
Second thing is, the setter is void, can't be void and int, remove int out of these kind of method :
public void int setMinute(int minute) {
this.minute = minute;
}
Third thing is, the hour is a property in myClock you can't use in other class:
private int hour;
The fourth point is you need to follow the convention. Class name must be Upper case first letter. For example myClock -> MyClock
Please also refer this to understand more about the class in Java:
https://docs.oracle.com/javase/tutorial/java/concepts/class.html
After fixing all above points, I believe you can understand and fix your code. If not, just ping me.
Hope this help!
|
[
"meta.stackexchange",
"0000111452.txt"
] | Q:
106% complete! Strunk and white progress in review pane
Possible Duplicate:
“Your review progress” showing target badge that I've already received
So as far as I know, I haven't made very many edits today. Judging by my history, I have 4 edits and/or retags ("revisions" as it calls them) in the last two days. When I go to the review page, I see a handy-dandy review progress screen on the side. Here's a snapshot:
Don't get me wrong. I'm not saying I should have Strunk and White. It's quite obvious that I have some retags or some other revisions that do not count towards Strunk and White, or I'd have it by now. And that's fine. I'm just pointing out the sidebar is a bit misleading.
A:
I just fixed an issue where Strunk & White was not counting edits on deleted posts, yet the little side bar was.
Now there are 2 cases where the sidebar may be out of sync:
We grant badges at the slowest once every hour. The sidebar may be indicating you are about to get the badge.
We cache the fact you have, or do not have, the badge for 240 seconds.
In future, if you reached more than 100% and have waited an hour, let me know.
|
[
"stackoverflow",
"0017340564.txt"
] | Q:
Why does IE not send the Kerberos ticket information to my JBoss on Linux?
I'm trying to implement SSO using a Windows client and JBoss. Own my development PC, JBoss runs on Windows 7, on the development server, it runs on (Red Hat) Linux.
There's a JBoss Negotiation Toolkit which allows me to check whether the Negiation header is arriving correctly.
The BasicNegotiation test works fine as long as I have JBoss running on my own PC, using localhost. The sent header is
Authorization: Negotiate YHgGBisGAQUFAqBuMGygMDAuBgorBgEEAYI3AgIKB... (plus some more bytes)
The test's response is
Negotiation Toolkit
Basic Negotiation
WWW-Authenticate - Negotiate YHgGBisGAQUFAqBuMGygMDAuBgorBgEEAYI3AgIK...
NegTokenInit
Message Oid - SPNEGO
Mech Types - {NTLM} {Kerberos V5 Legacy} {Kerberos V5} {1.3.6.1.4.1.311.2.2.30}
Req Flags -
Mech Token -TlRMTVNTUAABAAAAl7II4gQABAAyAAAACgAKACgAAAAGAbAdAAAAD0lQSUVWMTAwMjVJUElF
Mech List Mic -
But on the Linux server, the same test doesn't work. The base reason (I guess) is that the header looks different:
Authorization: Negotiate TlRMTVNTUAABAAAAl4II4gAAAAAAAAAAAAAAAAAAAAAGAbAdAAAADw==
And then the JBoss Negotiation Toolkit makes a fallback to NTML Authentication, which I don't want and which appears as error in the webapp's output.
Negotiation Toolkit
NTLM Negotiation
WWW-Authenticate - Negotiate TlRMTVNTUAABAAAAl4II4gAAAAAAAAAAAAAAAAAAAAAGAbAdAAAADw==
NTLM - Negotiate_Message
Warning, this is NTLM, only SPNEGO is supported!
Negotiate Flags - (encryption56Bit)(explicitKeyExchange)(sessionKeyExchange128Bit)
negotiateVersion)(ntlm2)(alwaysSign)(ntlm)(lmKey)(sign)(requestTarget)(oem)(unicode)
Domain Name = null - {length=0}{maxLength=0}{offset=0}
Workstation Name = null - {length=0}{maxLength=0}{offset=0}
Version - ?
I configured both Internet Explorer and Firefox to send the Negotiation header, and they both fail with the Linux server.
What am I doing wrong?
By the way: I read somewhere that Windows always sends the Kerberos Negotiation header on local machines - is that true?
A:
Thanks for the answers. In our case the problem was that we have two Windows domains. I was trying to access the Linux server in the domain A with the Windows Browser in the domain B. Obviously, that doesn't work...
|
[
"pt.stackoverflow",
"0000149630.txt"
] | Q:
Android, como fazer a segurança em JSON?
Uso Volley para fazer requisição POST a uma url que retorna dados do usuario... Mas da para ver esses dados, criando um simples formulario html com action setado para a url 192.168.0.101/projeto/user.php . Ai mostra todo o JSON... como evitar que o cara veja esses dados sem prejudicar o app quando for listar esses dados no recyclerview?
OBS: Usei header("Location: www.teste.com"); e redireciona sem mostrar o JSON ao possivel "hacker", MAS nao lista os dados no app
PHP:
<?php
require_once('config.php');
require_once 'classes/BD.class.php';
BD::conn();
if(isset($_POST['user']) && $_POST['user'] != ""){
$user = (int)$_POST['user'];
$searchPhotos = BD::conn()->prepare("SELECT * FROM `photos` WHERE `id_user` = ? ORDER BY `id` DESC");
$searchPhotos->execute(array($user));
$resultPhotos = $searchPhotos->rowCount();
$searchQtdFollowers = BD::conn()->prepare("SELECT id FROM `follows` WHERE `user` = ?");
$searchQtdFollowers->execute(array($user));
$resultFollowers = $searchQtdFollowers->rowCount();
$searchQtdFollowing = BD::conn()->prepare("SELECT id FROM `follows` WHERE `follower` = ?");
$searchQtdFollowing->execute(array($user));
$resultFollowing = $searchQtdFollowing->rowCount();
$array = array(
"photos" => $resultPhotos,
"followers" => $resultFollowers,
"following" => $resultFollowing
);
$result[] = array_map("utf8_encode", $array);
while($data = $searchPhotos->fetch(PDO::FETCH_ASSOC)){
$array = array(
"photo" => PATH.$data["photo"],
"date_creation" => date('d/m/Y', strtotime($data["date_creation"]))
);
$result[] = array_map("utf8_encode", $array);
}
header('Content-type: application/json');
echo json_encode($result);
}
?>
A:
Existem diversos métodos de segurança para este caso, no entanto um método básico, que é o mínimo a fazer, seria você usar uma chave criptografada nas duas pontas da conexão. Neste primeiro caso, usando requisição HTTP Get e passando como parâmetro sua chave através de seu aplicativo. Exemplo:
http://192.168.0.101/projeto/user.php?chave=mistersatanderrotoucell
Neste caso, sua aplicação enviaria um dado criptografado através do parâmetro chave, considerando que o mistersatanderrotoucell já seria um dado criptografado.
Para recuperar este valor no PHP, utilizamos as seguintes linhas de código:
echo $_GET['chave'];
Sendo assim, seria necessário fazer uma verificação confirmando se a chave recebida está correta ou não. Desta forma:
$minha_chave = mistersatanderrotoucell;
if($_GET['chave'] == $minha_chave){
//exibe json
} else{
echo "chave incorreta";
}
Ou também, como você já está usando HTTP POST para receber o valor do atributo user, daria para você acrescentar mais uma condição para receber a 'chave' desta forma:
if(isset($_POST['user'])
&& $_POST['user'] != ""
&& $_GET['chave'] == $minha_chave){
//Exibe json
} else{
echo "chave incorreta";
}
POST é mais seguro que o GET porque as informações passadas pelos
usuários nunca é visível na URL.
Vai depender da sua criatividade. Boa sorte!
|
[
"stackoverflow",
"0020664588.txt"
] | Q:
set up Xerces on ubuntu 12.04 to use with cmake and clang
I want to use Xerces in my project, which I compile with the help of cmake and clang.
What I did is:
download source
extract it to a folder called 'xerces-c-3.1.1'
cd into that folder
./configure
make
make install
Then I wrote LINK_DIRECTORIES(/usr/local/lib) into my CMakeLists.txt, and #include <xercesc/parsers/XercesDOMParser.hpp> into my main.cpp.
It compiles fine, but linking doesn't work.
I get the following results:
Linking CXX executable DG5_RE
CMakeFiles/DG5_RE.dir/main.cpp.o: In function `xercesc_3_1::XMLAttDefList::~XMLAttDefList()':
/home/reissmann/Dokumente/DGFromRepo/Source_Cpp_RE/main.cpp:(.text._ZN11xercesc_3_113XMLAttDefListD0Ev[_ZN11xercesc_3_113XMLAttDefListD0Ev]+0x1e): undefined reference to `xercesc_3_1::XMemory::operator delete(void*)'
CMakeFiles/DG5_RE.dir/main.cpp.o: In function `xercesc_3_1::DTDEntityDecl::~DTDEntityDecl()':
/home/reissmann/Dokumente/DGFromRepo/Source_Cpp_RE/main.cpp:(.text._ZN11xercesc_3_113DTDEntityDeclD0Ev[_ZN11xercesc_3_113DTDEntityDeclD0Ev]+0x1e): undefined reference to `xercesc_3_1::XMemory::operator delete(void*)'
CMakeFiles/DG5_RE.dir/main.cpp.o: In function `xercesc_3_1::DTDEntityDecl::~DTDEntityDecl()':
/home/reissmann/Dokumente/DGFromRepo/Source_Cpp_RE/main.cpp:(.text._ZN11xercesc_3_113DTDEntityDeclD2Ev[_ZN11xercesc_3_113DTDEntityDeclD2Ev]+0x11): undefined reference to `xercesc_3_1::XMLEntityDecl::~XMLEntityDecl()'
CMakeFiles/DG5_RE.dir/main.cpp.o:(.rodata._ZTVN11xercesc_3_113XMLAttDefListE[_ZTVN11xercesc_3_113XMLAttDefListE]+0x20): undefined reference to `xercesc_3_1::XMLAttDefList::isSerializable() const'
CMakeFiles/DG5_RE.dir/main.cpp.o:(.rodata._ZTVN11xercesc_3_113XMLAttDefListE[_ZTVN11xercesc_3_113XMLAttDefListE]+0x28): undefined reference to `xercesc_3_1::XMLAttDefList::serialize(xercesc_3_1::XSerializeEngine&)'
CMakeFiles/DG5_RE.dir/main.cpp.o:(.rodata._ZTVN11xercesc_3_113XMLAttDefListE[_ZTVN11xercesc_3_113XMLAttDefListE]+0x30): undefined reference to `xercesc_3_1::XMLAttDefList::getProtoType() const'
CMakeFiles/DG5_RE.dir/main.cpp.o:(.rodata._ZTVN11xercesc_3_113DTDEntityDeclE[_ZTVN11xercesc_3_113DTDEntityDeclE]+0x20): undefined reference to `xercesc_3_1::DTDEntityDecl::isSerializable() const'
CMakeFiles/DG5_RE.dir/main.cpp.o:(.rodata._ZTVN11xercesc_3_113DTDEntityDeclE[_ZTVN11xercesc_3_113DTDEntityDeclE]+0x28): undefined reference to `xercesc_3_1::DTDEntityDecl::serialize(xercesc_3_1::XSerializeEngine&)'
CMakeFiles/DG5_RE.dir/main.cpp.o:(.rodata._ZTVN11xercesc_3_113DTDEntityDeclE[_ZTVN11xercesc_3_113DTDEntityDeclE]+0x30): undefined reference to `xercesc_3_1::DTDEntityDecl::getProtoType() const'
CMakeFiles/DG5_RE.dir/main.cpp.o:(.rodata._ZTIN11xercesc_3_113DTDEntityDeclE[_ZTIN11xercesc_3_113DTDEntityDeclE]+0x10): undefined reference to `typeinfo for xercesc_3_1::XMLEntityDecl'
clang: error: linker command failed with exit code 1 (use -v to see invocation)
make[2]: *** [DG5_RE] Fehler 1
make[1]: *** [CMakeFiles/DG5_RE.dir/all] Fehler 2
make: *** [all] Fehler 2
What went wrong, and what is the appropriate solution?
Many thanks in advance.
A:
Use the FindXercesC is an easy and quick solution.
include(FindXercesC)
find_package(XercesC REQUIRED)
include_directories( ${XercesC_INCLUDE_DIR} )
target_link_libraries ( ${PROJECT_NAME} ${XercesC_LIBRARY} )
A:
You probably want to replace your use of link_directories with find_library and target_link_libraries.
link_directories only provides paths which the linker can search for dependencies - it doesn't actually specify what those dependencies are. Furthermore, from the docs:
Note that this command is rarely necessary. Library locations returned by find_package() and find_library() are absolute paths. Pass these absolute library file paths directly to the target_link_libraries() command. CMake will ensure the linker finds them.
I'm not familiar with Xerces, but assuming it has only 1 library called "libxerces-c.a", you should probably have something like:
find_library(XercesLibrary NAMES xerces-c PATHS /usr/local/lib)
if(NOT XercesLibrary)
message(FATAL_ERROR "Failed to find the Xerces library.")
endif()
...
target_link_libraries(MyExe ${XercesLibrary})
You may need to significantly extend this find_library process; more PATHS than just /usr/local/lib could be given; you may need to find more than 1 library (e.g. a Debug version on Windows?), etc. If the library has different names on different operating systems, you may need to provide more NAME options (remember CMake may adjust the search name - see CMAKE_FIND_LIBRARY_PREFIXES and CMAKE_FIND_LIBRARY_SUFFIXES).
Also, a more helpful error message can be invaluable if the find attempt fails. You could suggest to set a variable (e.g. XERCES_LIB_DIR) indicating the location of the Xerces library, and this could be added to the list of PATHS in the find_library call.
|
[
"stackoverflow",
"0044961622.txt"
] | Q:
How to call flask migrate api in script
I have a database db. I want to judge if flask_migrate has created tables in db. If not, upgrade db.
There are commands, but no examples about calling migrate, upgrade in python script.
The test files in flask_migrate also run commands:
(o, e, s) = run_cmd('python app.py db migrate')
A:
This should do the trick for you.
from flask_migrate import upgrade
@ns.route('/migrate_db')
class Units(Resource):
def get(self):
upgrade(directory=<path_to_migrations_folder>)
|
[
"math.stackexchange",
"0000755539.txt"
] | Q:
Equivalent condition for interpolation polynomial
Let $(x_1,y_1),...,(x_n,y_n)\in \mathbb{R}^2 $, where $x_i\neq x_j$ if $i\neq j$. Let $p$ be a polynomial such that
$$\det\begin{pmatrix}
p(x)& 1 & x & x^2 &\dots & x^n \\
y_0 & 1 & x_0 & x_0^2 &\dots &x_0^n \\
y_1 & 1 & x_1 & x_1^2 &\dots &x_1^n \\
\vdots & & & & & \vdots \\
y_n & 1 & x_n & x_n^2 &\dots & x_n^n
\end{pmatrix}=0. $$
Then $p(x_k)=y_k ,\forall k=1,...,n$.
My ideas: We should compute the determinant using Laplace's formula, although I can't see a nice pattern to do a proof by induction or to conclude the proposition.
Thanks for the help
bests
bjn
A:
Hint. Put $x=x_0$ and subtract the second row from the first row. The determinant is then equal to
$$
\det\pmatrix{p(x_0)-y_0&0_{1\times(n+1)}\\ \ast&V}=(p(x_0)-y_0)\det(V),
$$
where $V$ is a Vandermonde matrix. In order that this is zero, ...
|
[
"stackoverflow",
"0028766804.txt"
] | Q:
.NET MVC - pass List of runtime type to Grid
I have List<MyType> list and need to pass list to @Html.Grid((IEnumerable<MyType>)list, "MvcGrid/customGridView") in my view. MyType was created at runtime. Can you provide some example code to do this??
Concreatelly:
In my controller i have this code:
public ActionResult dataRuntime()
{
var myType = CompileResultType();
var myObject = Activator.CreateInstance(myType);
var myObject2 = Activator.CreateInstance(myType);
Type listType = typeof(List<>).MakeGenericType(new Type[] { myObject.GetType() });
IList listt = (IList)Activator.CreateInstance(listType);
listt.Add(myObject);
listt.Add(myObject2);
ViewData["type"] = myType;
return View(list);
}
So I have List<MyType> with two MyType objects. In view I have:
@{
Type t = (Type)ViewData["type"];
var list = Model;
}
and need to call method like this:
@Html.Grid((IEnumerable<MyType>)list, "MvcGrid/customGridView")
So I need to do something like:
@Html.Grid((IEnumerable<t>)list, "MvcGrid/customGridView")
but it doesn't work, obviously.
So I tried do this:
@{
// For non-public methods, you'll need to specify binding flags too
System.Reflection.MethodInfo method = Html.GetType().GetMethod("Grid")
.MakeGenericMethod(new Type[] { t });
var g = method.Invoke(Html, new object[] { list, "MvcGrid/customGridView" });
}
but I get an error:
System.NullReferenceException: Object reference not set to an instance
of an object
which is logic, because HtmlHelper doesn't have method Grid.
Grid class is defined here:
https://github.com/leniel/Grid.Mvc/blob/master/GridMvc/Grid.cs
Do someone know, how to make it work?
A:
Grid is actually static method, so you do not pass Html as the first parameter to method.Invoke.
In case of static method, Invoke ignores the first parameter, so you can pass in just null for example. Do not forget to put Html into the parameters array:
method.Invoke(null, new object[] { Html, list, "MvcGrid/customGridView" });
Edit: and also you do not get the reference to Grid method from HtmlHelper type. Use intellisense to find out on which type is the Grid method defined and use that type instead of Html.GetType()
|
[
"ru.stackoverflow",
"0001074939.txt"
] | Q:
Как произвести извлечение JSON формата из PostgreSQL правильным образом через NetBeans?
Я использую EclipseLink JPA 2.1. в NetBeans.
Создал табличку в БД PostgreSQL:
CREATE TABLE public.test_json (
id serial NOT NULL,
json_data json NOT NULL,
CONSTRAINT test_json_pkey PRIMARY KEY (id)
);
В NetBeans выполнил команду "Entity Classes From DataBase", и попытался произвести отражение табличного представления из БД на мой Entity класс.
/*
* To change this license header, choose License Headers in Project Properties.
* To change this template file, choose Tools | Templates
* and open the template in the editor.
*/
package javaapplication6;
import java.io.Serializable;
import java.sql.Clob;
import javax.persistence.Basic;
import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.Lob;
import javax.persistence.NamedQueries;
import javax.persistence.NamedQuery;
import javax.persistence.Table;
import javax.xml.bind.annotation.XmlRootElement;
/**
*
* @author ramze
*/
@Entity
@Table(name = "test_geometry")
@XmlRootElement
@NamedQueries({
@NamedQuery(name = "TestGeometry.findAll", query = "SELECT t FROM TestGeometry t")
, @NamedQuery(name = "TestGeometry.findById", query = "SELECT t FROM TestGeometry t WHERE t.id = :id")})
public class TestGeometry implements Serializable {
private static final long serialVersionUID = 1L;
@Id
@GeneratedValue(strategy = GenerationType.IDENTITY)
@Basic(optional = false)
@Column(name = "id")
private Integer id;
@Lob
@Column(name = "geom")
private Object geom;
public TestGeometry() {
}
public TestGeometry(Integer id) {
this.id = id;
}
public Integer getId() {
return id;
}
public void setId(Integer id) {
this.id = id;
}
public Object getGeom() {
return geom;
}
public void setGeom(Serializable geom) {
this.geom = geom;
}
@Override
public int hashCode() {
int hash = 0;
hash += (id != null ? id.hashCode() : 0);
return hash;
}
@Override
public boolean equals(Object object) {
// TODO: Warning - this method won't work in the case the id fields are not set
if (!(object instanceof TestGeometry)) {
return false;
}
TestGeometry other = (TestGeometry) object;
if ((this.id == null && other.id != null) || (this.id != null && !this.id.equals(other.id))) {
return false;
}
return true;
}
@Override
public String toString() {
return "javaapplication6.TestGeometry[ id=" + id + " ]";
}
}
После того как это было успешно выполнено, я попытался присоединиться к моей БД и извлечь оттуда информацию:
EntityManagerFactory emf = Persistence.createEntityManagerFactory("Name_of_my_connection");
где Name_of_my_connection = 'JavaApplication5PU'
Но Java не понимает JSON формат и выдала мне следующую ошибку.
debug:
Exception in thread "main" Local Exception Stack:
Exception [EclipseLink-30005] (Eclipse Persistence Services - 2.5.2.v20140319-9ad6abd): org.eclipse.persistence.exceptions.PersistenceUnitLoadingException
Exception Description: An exception was thrown while searching for persistence archives with ClassLoader: sun.misc.Launcher$AppClassLoader@18b4aac2
Internal Exception: javax.persistence.PersistenceException: Exception [EclipseLink-28018] (Eclipse Persistence Services - 2.5.2.v20140319-9ad6abd): org.eclipse.persistence.exceptions.EntityManagerSetupException
Exception Description: Predeployment of PersistenceUnit [JavaApplication5PU] failed.
Internal Exception: Exception [EclipseLink-7164] (Eclipse Persistence Services - 2.5.2.v20140319-9ad6abd): org.eclipse.persistence.exceptions.ValidationException
Exception Description: The type [class java.lang.Object] for the attribute [jsonData] on the entity class [class javaapplication5.TestJson] is not a valid type for a lob mapping. For a lob of type BLOB, the attribute must be defined as a java.sql.Blob, byte[], Byte[] or a Serializable type. For a lob of type CLOB, the attribute must be defined as a java.sql.Clob, char[], Character[] or String type.
at org.eclipse.persistence.exceptions.PersistenceUnitLoadingException.exceptionSearchingForPersistenceResources(PersistenceUnitLoadingException.java:127)
at org.eclipse.persistence.jpa.PersistenceProvider.createEntityManagerFactoryImpl(PersistenceProvider.java:107)
at org.eclipse.persistence.jpa.PersistenceProvider.createEntityManagerFactory(PersistenceProvider.java:177)
at javax.persistence.Persistence.createEntityManagerFactory(Persistence.java:79)
at javax.persistence.Persistence.createEntityManagerFactory(Persistence.java:54)
at javaapplication5.JavaApplication5.main(JavaApplication5.java:23)
Caused by: javax.persistence.PersistenceException: Exception [EclipseLink-28018] (Eclipse Persistence Services - 2.5.2.v20140319-9ad6abd): org.eclipse.persistence.exceptions.EntityManagerSetupException
Exception Description: Predeployment of PersistenceUnit [JavaApplication5PU] failed.
Internal Exception: Exception [EclipseLink-7164] (Eclipse Persistence Services - 2.5.2.v20140319-9ad6abd): org.eclipse.persistence.exceptions.ValidationException
Exception Description: The type [class java.lang.Object] for the attribute [jsonData] on the entity class [class javaapplication5.TestJson] is not a valid type for a lob mapping. For a lob of type BLOB, the attribute must be defined as a java.sql.Blob, byte[], Byte[] or a Serializable type. For a lob of type CLOB, the attribute must be defined as a java.sql.Clob, char[], Character[] or String type.
at org.eclipse.persistence.internal.jpa.EntityManagerSetupImpl.createPredeployFailedPersistenceException(EntityManagerSetupImpl.java:1954)
at org.eclipse.persistence.internal.jpa.EntityManagerSetupImpl.predeploy(EntityManagerSetupImpl.java:1945)
at org.eclipse.persistence.internal.jpa.deployment.JPAInitializer.callPredeploy(JPAInitializer.java:98)
at org.eclipse.persistence.jpa.PersistenceProvider.createEntityManagerFactoryImpl(PersistenceProvider.java:96)
... 4 more
Caused by: Exception [EclipseLink-28018] (Eclipse Persistence Services - 2.5.2.v20140319-9ad6abd): org.eclipse.persistence.exceptions.EntityManagerSetupException
Exception Description: Predeployment of PersistenceUnit [JavaApplication5PU] failed.
Internal Exception: Exception [EclipseLink-7164] (Eclipse Persistence Services - 2.5.2.v20140319-9ad6abd): org.eclipse.persistence.exceptions.ValidationException
Exception Description: The type [class java.lang.Object] for the attribute [jsonData] on the entity class [class javaapplication5.TestJson] is not a valid type for a lob mapping. For a lob of type BLOB, the attribute must be defined as a java.sql.Blob, byte[], Byte[] or a Serializable type. For a lob of type CLOB, the attribute must be defined as a java.sql.Clob, char[], Character[] or String type.
at org.eclipse.persistence.exceptions.EntityManagerSetupException.predeployFailed(EntityManagerSetupException.java:230)
... 8 more
Caused by: Exception [EclipseLink-7164] (Eclipse Persistence Services - 2.5.2.v20140319-9ad6abd): org.eclipse.persistence.exceptions.ValidationException
Exception Description: The type [class java.lang.Object] for the attribute [jsonData] on the entity class [class javaapplication5.TestJson] is not a valid type for a lob mapping. For a lob of type BLOB, the attribute must be defined as a java.sql.Blob, byte[], Byte[] or a Serializable type. For a lob of type CLOB, the attribute must be defined as a java.sql.Clob, char[], Character[] or String type.
at org.eclipse.persistence.exceptions.ValidationException.invalidTypeForLOBAttribute(ValidationException.java:1132)
at org.eclipse.persistence.internal.jpa.metadata.converters.LobMetadata.process(LobMetadata.java:124)
at org.eclipse.persistence.internal.jpa.metadata.accessors.mappings.MappingAccessor.processLob(MappingAccessor.java:1707)
at org.eclipse.persistence.internal.jpa.metadata.accessors.mappings.BasicAccessor.processLob(BasicAccessor.java:524)
at org.eclipse.persistence.internal.jpa.metadata.accessors.mappings.MappingAccessor.processMappingConverter(MappingAccessor.java:1771)
at org.eclipse.persistence.internal.jpa.metadata.accessors.mappings.MappingAccessor.processMappingValueConverter(MappingAccessor.java:1796)
at org.eclipse.persistence.internal.jpa.metadata.accessors.mappings.BasicAccessor.process(BasicAccessor.java:419)
at org.eclipse.persistence.internal.jpa.metadata.MetadataDescriptor.processMappingAccessors(MetadataDescriptor.java:1536)
at org.eclipse.persistence.internal.jpa.metadata.accessors.classes.ClassAccessor.processMappingAccessors(ClassAccessor.java:1648)
at org.eclipse.persistence.internal.jpa.metadata.accessors.classes.EntityAccessor.processMappingAccessors(EntityAccessor.java:1234)
at org.eclipse.persistence.internal.jpa.metadata.accessors.classes.EntityAccessor.process(EntityAccessor.java:697)
at org.eclipse.persistence.internal.jpa.metadata.MetadataProject.processStage2(MetadataProject.java:1793)
at org.eclipse.persistence.internal.jpa.metadata.MetadataProcessor.processORMMetadata(MetadataProcessor.java:576)
at org.eclipse.persistence.internal.jpa.deployment.PersistenceUnitProcessor.processORMetadata(PersistenceUnitProcessor.java:585)
at org.eclipse.persistence.internal.jpa.EntityManagerSetupImpl.predeploy(EntityManagerSetupImpl.java:1869)
... 6 more
C:\Users\ramze\AppData\Local\NetBeans\Cache\8.2\executor-snippets\debug.xml:83: Java returned: 1
BUILD FAILED (total time: 4 seconds)
Подскажите, пожалуйста, что нужно сделать, чтобы исправить эту ошибку? Как правильным образом отразить табличное представление, где один из столбцов представляет собой JSON формат???
A:
Короче, я сам решил это:
1) Вот моя таблица в базе:
2) В автоматически сформированном ORM-классе TestJson:
/*
* To change this license header, choose License Headers in Project Properties.
* To change this template file, choose Tools | Templates
* and open the template in the editor.
*/
package javaapplication5;
import java.io.Serializable;
import javax.persistence.Basic;
import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.Lob;
import javax.persistence.NamedQueries;
import javax.persistence.NamedQuery;
import javax.persistence.Table;
import javax.xml.bind.annotation.XmlRootElement;
/**
*
* @author ramze
*/
@Entity
@Table(name = "test_json")
@XmlRootElement
@NamedQueries({
@NamedQuery(name = "TestJson.findAll", query = "SELECT t FROM TestJson t")
, @NamedQuery(name = "TestJson.findById", query = "SELECT t FROM TestJson t WHERE t.id = :id")})
public class TestJson implements Serializable {
private static final long serialVersionUID = 1L;
@Id
@GeneratedValue(strategy = GenerationType.IDENTITY)
@Basic(optional = false)
@Column(name = "id")
private Integer id;
@Basic(optional = false)
@Lob
@Column(name = "json_data")
private Object jsonData;
public TestJson() {
}
public TestJson(Integer id) {
this.id = id;
}
public TestJson(Integer id, Object jsonData) {
this.id = id;
this.jsonData = jsonData;
}
public Integer getId() {
return id;
}
public void setId(Integer id) {
this.id = id;
}
public Object getJsonData() {
return jsonData;
}
public void setJsonData(Object jsonData) {
this.jsonData = jsonData;
}
@Override
public int hashCode() {
int hash = 0;
hash += (id != null ? id.hashCode() : 0);
return hash;
}
@Override
public boolean equals(Object object) {
// TODO: Warning - this method won't work in the case the id fields are not set
if (!(object instanceof TestJson)) {
return false;
}
TestJson other = (TestJson) object;
if ((this.id == null && other.id != null) || (this.id != null && !this.id.equals(other.id))) {
return false;
}
return true;
}
@Override
public String toString() {
return "javaapplication5.TestJson[ id=" + id + " ]";
}
}
Изменил
@Lob
@Column(name = "json_data")
private Object jsonData;
public Object getJsonData() {
return jsonData;
}
на
@Lob
@Column(name = "json_data")
private String jsonData;
public String getJsonData() {
return jsonData;
}
Выполнил вот этот код:
EntityManagerFactory emf = Persistence.createEntityManagerFactory("JavaApplication5PU");
EntityManager em = emf.createEntityManager();
TestJson test_json = em.createNamedQuery("TestJson.findAll", TestJson.class).getSingleResult();
И в переменной test_json получил адекватный строковый json:
|
[
"english.stackexchange",
"0000072269.txt"
] | Q:
What does “root against something” mean? Isn’t it an idiom?
I found an article titled “The Schadenfreude Sports Fan” in today’s (June 23) New York Times followed by the lead copy:
“Figuring out which teams to root against is a nuanced and delicate matter.”
Though "root against"seems to mean "smashing down somebody, something," I'm not sure. So I checked on Cambridge, Oxford, and Merriam-Webster online dictionaries. None of them registers “root against” as an idiom, though they register root around (for / through/ out) as the idioms meaning scratch around, or terminating.
I also found many instances of using “root against” in sports related articles, e.g.;
-Figuring out which teams to root against is a nuanced and delicate matter.–New York Times.
-Because you root against the Yankees harder in October than you do the other 11 months.-Sport Illustrated.
-Only mean-spirited people root against Tim Tebow: The hate makes little sports sense- Culturemap Houston.
Google Ngram also shows the trend of continued increase of usage of the words “root against” since 1880 after bottoming out during ca. 1960 -1900.
What does “root against something” mean? Is it only used for sports related context? Isn’t it a "generic" idiom as against "sports speciffic expression"
A:
You can root for someone or something, and you can root someone on, too.
So “rooting against” is the opposite of rooting for.
EDIT
Due to @Brendon’s request, the OED’s root v.2 has these two applicable subsenses for sense 4:
4a. intr. To cheer for or lend support to a person or group, esp. a sports team; to wish for a person or group's success in a particular endeavour. Chiefly with for.
4b. trans. To cheer or urge (a person, team, etc.) on.
But that’s nothing: just wait till you get a gander of the citations under its distinctly antipodean sense 6. :)
|
[
"stackoverflow",
"0055220875.txt"
] | Q:
Travis-Ci not importing utilities
I have a script of the following shape:
main.py
utilities/
__init__.py
foo.py
In main.py I import the function bar from foo.py:
from utilities.foo import bar
However, Travis cannot import this, returning:
ModuleNotFoundError: No module named 'utilities.foo'
How can I solve this?
A:
I don't understand how or why, but changing the name of the utilities folder to utils solves the issue.
|
[
"stackoverflow",
"0025561554.txt"
] | Q:
Find triple sets in Pig Latin
Is it possible to find triple datasets in Pig? Let's say your data is:
bag1 Apple
bag1 Orange
bag2 Apple
bag2 Orange
bag2 Pineapple
bag3 Apple
bag3 Orange
bag3 Pineapple
bag4 Orange
bag5 Apple
bag5 Banana
In data above I want to count occurrence of (Apple,Orange,Pineapple)set inside each bag, which happens twice for bag2 and bag3. Is that possible?
A:
A = LOAD 'BAG.csv' using PigStorage(' ') as (bag:Chararray, fruit:Chararray);
B = GROUP A by $0;
C = FILTER B BY COUNT(A)==3;
D = FOREACH C GENERATE group, A.$1 as FRUITS;
DUMP D;
|
[
"stackoverflow",
"0009321913.txt"
] | Q:
Can I remove a merge/changeset from the past?
Say I am using git by creating a new branch for each feature, then merging into master.
So each merge is very narrow in that it is for a specific feature.
After 10 commits like this, can I go back and remove the 5th merge somehow?
Say it was a feature I didn't want.
A:
We do this constantly. Here is how: http://dymitruk.com/blog/2012/02/05/branch-per-feature/
You want to reset master to just before the 5th merge. Now merge in the rest.
One suggestion would be to use a release candidate branch instead of master. Use master to mark what was released.
|
[
"stackoverflow",
"0057207517.txt"
] | Q:
Counting the frequency of keywords in a specified list
I am trying to count the number of times specific keywords occur in a string. Let us suppose I have a string and I want to count how many times a few keywords occur in the string. And these keywords are stored in a list. After the program counts the number of times a word occurs it stores it in an array.
I've written the following program
var para = "I code code code Javascript"
var keywords = ['code',"I"];
var arr = [];
for(let i = 0; i < keywords.length; i++){
arr[i] = (para.match(/keywords[i]/g) || []).length;
}
keyword[i] doesn't seem to be working
A:
A way to solve this is to create the regex first...because string.match(regex) accepts a regex as the first argument but you are passing the stringkeywords[i] as the pattern (which will return 0 because that string doesn't exist on para) and for that we use RegExp Constructor to create the regex that we want to match first then we pass that to string.match(regex) :
var para = "I code code code Javascript"
var keywords = ['code',"I"];
var arr = [];
for(let i = 0; i < keywords.length; i++){
var reg = new RegExp(keywords[i],'g')
arr[i] = (para.match(reg) || []).length;
console.log(arr[i])
}
|
[
"stackoverflow",
"0028745132.txt"
] | Q:
Which takes precedence, Gradle build types or flavors?
Say I have a constant defined at both levels: in the build type I set it to "mybuild" and in the flavor I set it to "myflavor".
Such as in here:
buildTypes {
debug {
resValue "string", "analytics_key", "XXX_SANDBOX_KEY_XXX"
}
}
productFlavors {
appA {
resValue "string", "analytics_key", "XXX_KEY_FOR_A_XXX"
}
appB {
resValue "string", "analytics_key", "XXX_KEY_FOR_A_XXX"
}
}
I want to send the events of the different apps (thta is, flavors) to different accounts in my analytics platform. But, if I'm debugging, I want to send them all to my sandbox account.
The original question is: which takes precedence? From my test, I can already answer that: the one in the build type.
However, the more interesting one is: is this guaranteed?
(Or, is there a better way to do this?)
A:
is this guaranteed?
Build types generally are considered higher priority than are product flavors for things at the same level (e.g., the same module). Quoting the documentation:
Usually, the Build Type configuration is an overlay over the other configuration. For instance, the Build Type's packageNameSuffix is appended to the Product Flavor's packageName.
Manifest merging, though, is rather complicated, requiring its own set of docs.
In your case, you are creating resources. In that case, it should follow the same rules as if you had put these values as string resources in relevant sourcesets:
All resources (Android res and assets) are used using overlay priority where the Build Type overrides the Product Flavor, which overrides the main sourceSet.
If resValue started behaving differently than the equivalent using sourcesets, I would consider that to be a bug.
|
[
"stackoverflow",
"0060183316.txt"
] | Q:
Show Image Response Null If image Is Not Submitted In Laravel
I'm Submitting data through postman in Laravel. I need to show the null value if data do not insert during submitting(In JSON response). But It did not show the image in response I need to show an image response also Null
My Store Code is
public function store(Request $request)
{
$screenshots = new Screenshots ;
$screenshots->user_id = $request->user_id;
$screenshots->name = $request->name;
$screenshots->size = $request->size;
if($request->hasFile('image')){
$fileNameExt = $request->file('image')->getClientOriginalName();
$fileName = pathinfo($fileNameExt, PATHINFO_FILENAME);
$fileExt = $request->file('image')->getClientOriginalExtension();
$fileNameToStore = $fileName.'.'.$fileExt;
$pathToStore = $request->image->storeAs('public/uploads/screenshots', $request->image->getClientOriginalName());
$screenshots->image = $fileNameToStore;
$screenshots->save();
};
$screenshots->save();
return $this->sendResponse($screenshots->toArray(), 'Command Send Successfully successfully.');
}
It is giving a null when any field is blank but if an image is blank I didn't any response.
For more clear please see attached screenshot
Getting Response Be like
{"success":true,"data":{"user_id":"2","name":null,"size":"3.4kb","updated_at":"2020-02-12 07:26:49","created_at":"2020-02-12 07:26:49","id":32},"message":"Command Send Successfully successfully."}
The response I need if the image is also blank
{"success":true,"data":{"user_id":"2","name":null,"size":"3.4kb","image":"null","updated_at":"2020-02-12 07:26:49","created_at":"2020-02-12 07:26:49","id":32},"message":"Command Send Successfully successfully."}
A:
please use below method to add default set null
// set in your model Screenshots
protected $attributes = array(
'image' => '',
);
OR
if($request->hasFile('image')){
$fileNameExt = $request->file('image')->getClientOriginalName();
$fileName = pathinfo($fileNameExt, PATHINFO_FILENAME);
$fileExt = $request->file('image')->getClientOriginalExtension();
$fileNameToStore = $fileName.'.'.$fileExt;
$pathToStore = $request->image->storeAs('public/uploads/screenshots', $request->image->getClientOriginalName());
$screenshots->image = $fileNameToStore;
$screenshots->save();
}else{
$screenshots->image = '';
}
|
[
"stackoverflow",
"0025817387.txt"
] | Q:
Add dictionary as value of dictionary in Python
I want to create a array of set in Python.
That is what i am trying to do with my code below
for doc in collection.find():
pageType = doc.get('pageType')
title = doc.get('title')
_id = doc.get('_id')
value = {'pageType' : pageType, 'id': _id}
setValues = pageDict.get(title)
if not setValues :
setValues = set()
pageDict[title] = setValues
setValues.add(value)
I get following error when running it
setValues.add(value)
TypeError: unhashable type: 'dict'
I found that i cannot set the mutable value as a key of the dictionary, but i am here adding it as value of dictionary. Essentially, my value of dictionary is a set which contains another dictionary.
How can i achieve this in python? What other data structures can i used to achieve this?
A:
i used frozsenSet to add the value to the set and it worked
setValues.add(frozenSet(value.items())
|
[
"math.stackexchange",
"0000700336.txt"
] | Q:
Free fall with resistance: solution to the ODE
I'm having trouble solving this ODE:
$$\ddot x = \mu \dot x^2 - g, \space \space x(0)=x_0$$
This is the ODE that determines the equation of motion of an object with air resistance. $\mu$ is a positive constant. This is what I've done:
Let $\dot x = v$ we have $v(0) = 0$ by assumption and the equation becomes:
$$\dot v = \mu v^2 - g$$
This is a Riccati differential equation. Recall that a Riccati differential equation has the form
$$\dot x = h(t) + f(t) x + g(t)x^2$$
In our case is $h(t) = -g$, $f(t) = 0$ and $g(t) = \mu$
To solve this kind of differential equations one has to guess a solution, which in this case I found be:
$$v_p(t) = \sqrt{g \over \mu}$$
$\implies y = {1 \over {v- \sqrt{g \over n}}}$ $\implies y(0) = \sqrt{n\over g}$ to find the solution $v(t)$ one has to solve the following differential equation:
$$\dot y = -(f(t) + 2v_pg(t))y-g(t)$$
This is what I've done:
\begin{align}
\dot y & = -(f(t) + 2v_pg(t))y-g(t) \\
& \dot y = -2 \sqrt{g\mu }\space y - \mu \space
& (1)
\end{align}
Now this is a linear inhomogeneous differential equation an the solution is given by the sum of the homogeneous solution $y_h(t)$ with the particular solution $y_p (t)$ The homogeneous solution comes from:
$$\dot y = -2 \sqrt{g\mu }\space y \implies y_h = y(0) e^{-2 \sqrt{g\mu }}$$
for the particular solution $y_p(t)$ is a little bit more complicated then to find it I substituted
$$y_p(t) = y(0)(t)e^{-2 \sqrt{g\mu }} = C_1 (t)e^{-2 \sqrt{g\mu }}$$
in the equation (1). This is what I get:
\begin{align}
y_p(t)& =C_1(t)' e^{-2 \sqrt{g\mu }} -2 \sqrt{g\mu }C_1(t)e^{-2 \sqrt{g\mu }} = -2 \sqrt{g\mu }C_1(t)e^{-2 \sqrt{g\mu }} - \mu
\end{align}
\begin{align}
\iff C_1(t)' e^{-2 \sqrt{g\mu }} & = -\mu
\end{align}
$$ \iff C_1(t) = {-\mu \over {2 \sqrt{g\mu }}}e^{2 \sqrt{g\mu }}$$
summarizing we have
$$y(t) = {1 \over v - \sqrt {g \over n}} = C_1(t)e^{-2 \sqrt{g\mu }} + y_h(t)= {-\mu \over {2 \sqrt{g\mu }}}e^{2 \sqrt{g\mu }}e^{-2 \sqrt{g\mu }} + y(0) e^{-2 \sqrt{g\mu }} $$
$$= {-\mu \over {2 \sqrt{g\mu }}} + y(0) e^{-2 \sqrt{g\mu }}$$
from here I tried to solve $y = {1 \over {v- \sqrt{g \over n}}}$ with respect to $v$ and then solve the last ODE $v = \dot x$ but I think that something has gone wrong.
Is there an alternative way to solve the original ODE? Is the method I've used the only one?
A:
As you asked for methods I decided to post an alternative. Here we use the trick of eliminating the inhomogeneity.
First, consider only the equation for $v(t)=\dot{x}(t)$,
$$\dot{v}=\mu v^2-g.$$ The inhomogeneity $-g$ prevents us from simple integration of the ODE, so let's make it disappear by defining $w(t)=v(t)-\gamma$, which leads to
$$\dot{w}=\mu w^2+2\mu\gamma w+\mu\gamma^2-g.$$ We see that the choice $\gamma=\sqrt{g/\mu}$ kills the constant term, leadig to the homogenous equation for $w$:
$$\frac{dw}{dt}=\mu w^2+2\sqrt{\mu g}w,$$ which now can directly be integrated:
$$\int_{w_0}^{w(t)} \frac{dw}{\mu w^2+2\sqrt{\mu g}w}=\int_0 ^t dt.$$ This can be solved using $\int dt/(at^2+bt)=-(2/b)\text{artanh} (2at/b+1)$ (for $b>0$) which gives
$$\frac{-1}{\sqrt{\mu g}}\text{artanh}\left( \mu w+1 \right)-C=t$$ with some integration constant $C$. We can solve this for $w$ and obtain
$$w(t)=\sqrt{\frac{g}{\mu}}\left( \tanh[-\sqrt{\mu g}(t+C)]-1 \right).$$ Transforming back to our original function $v$ gives
$$v(t)=w(t)+\gamma=\sqrt{\frac{g}{\mu}} \tanh[-\sqrt{\mu g}(t+C)],$$ and from the initial condition $v(0)=0$ it follows that $C=0$.
Now you can integrate $v=\dot{x}$ to get the position solution using that $\int dt \tanh(t)=\ln (\cosh x)$ arriving at
$$x(t)=x_0-\frac{1}{\mu}\ln\left[ \cosh(-\sqrt{\mu g}t) \right],$$
where the integration constant has been chosen such that $x(0)=x_0$.
|
[
"superuser",
"0000232721.txt"
] | Q:
How to avoid tilde ~ in Bash prompt?
I would like to remove the tilde from displaying within the PS1 variable.
My current PS1 string:
PS1="\h:\w\n$"
And the prompt looks like this:
lnx-hladky:/tmp/plugtmp
$
I don't like that the $HOME directory is displayed as tilde. Can this be avoided?
It causes problems, example:
lnx-hladky:~/DOC
$
Documentation says:
\w : the current working directory, with $HOME abbreviated with a tilde
\W: the basename of the current working directory, with $HOME abbreviated with a tilde
Is there any possibility to avoid $HOME being abbreviated with a tilde?
I have found one way around but I feel like it's overcomplicated:
PROMPT_COMMAND='echo -ne "\e[4;35m$(date +%T)\e[24m$(whoami)@$(hostname):$(pwd)\e[m\n"'
PS1=$
Can anyone propose a better solution? I have a feeling it's not quite OK to run so many commands just to get prompt. (date,whoami,hostname,pwd).
A:
bash runs expansions in the prompt; just make sure to escape them.
PS1='\h:$(pwd)\n$'
|
[
"stackoverflow",
"0033407217.txt"
] | Q:
How to parse a line with double character tokens
I'm trying to write an xtext parser to parse a simple markup language. The markup uses double characters for styling text. !! is used for bold. I'm struggling to work out how to create the grammar, in particular how to handle the double character symbols. As an example:
The following text !!is bold! !! but not this.
I want to parse this into the following AST:
Lines
Line
Text "The following text "
BoldText "is bold! "
Text " but not this."
Does anyone have any good approaches?
Should I use:
terminal BOLD: '!!'
or
Bold : '!' '!'
I'm thinking that I have to use the second rule. That to handle this I have to have single character terminals and then use parser rules for everything.
My grammar at the moment is:
grammar org.xtext.example.mydsl.MyDsl
import "http://www.eclipse.org/emf/2002/Ecore" as ecore
generate myDsl "http://www.xtext.org/example/mydsl/MyDsl"
Lines:
lines+=Line*
;
Line:
{Line} content+=(PlainText|BoldText)*
NL
;
PlainText:
text = Text
;
Text returns ecore::EString:
(CHAR|WS)+
;
BoldText:
BOLD
{BoldText} text += PlainText*
BOLD
;
terminal BOLD: '!!';
terminal WS: (' ' | '\t')+;
terminal NL: '\r'? '\n';
terminal CHAR: !(' '|'\t'|'\r'|'\n');
BUT this is getting warnings because it can match repetitions of PlainText OR (CHAR|WS)+ in Text and I don't know how to get rid of that?
A:
I would suggest defining the terminal as '!!' (first case), however '!' followed by another '!' (second case) should also work in this use-case.
How is your parser supposed to behave in the case where you have "!!!" in a row? In this case it is likely it will group the first two "!!" and leave the third as a literal '!'. I would suggest adding the ability to escape !s, e.g., "\!", so you could have "\!!!" for a literal '!' followed by '!!' terminal. Another idea here would be to implement some form of recursion to take only the rightmost pair as the '!!' terminal.
Best of luck!
|
[
"stackoverflow",
"0014171952.txt"
] | Q:
MYSQL Select update query multiple joins error
i am trying to update a variable row, in a variable table. This is my query:
// EDIT: removed double...
UPDATE `ec`.`category_id` AS `category_id`,`e`.`title` AS `title`,
`r`.`first_name` AS `first_name`,
`r`.`last_name` AS `last_name`,`r`.`email` AS `email`,
`r`.`comment` AS `comment`,`r`.`amount` AS `amount`,
`r`.`published` AS `published`,`r`.`transaction_id` AS `transaction_id`,
`r`.`register_date` AS `register_date`,
max((case `f`.`id` when 1 then `v`.`field_value` else '' end)) AS `pand`,
max((case `f`.`id` when 52 then `v`.`field_value` else '' end)) AS `achternaam`,
max((case `f`.`id` when 53 then `v`.`field_value` else '' end)) AS `voornaam`,
max((case `f`.`id` when 20 then `v`.`field_value` else '' end)) AS `gebdat`,
max((case `f`.`id` when 32 then `v`.`field_value` else '' end)) AS `geslacht`,
max((case `f`.`id` when 31 then `v`.`field_value` else '' end)) AS `kleinkind`,
max((case `f`.`id` when 21 then `v`.`field_value` else '' end)) AS `straat`,
max((case `f`.`id` when 54 then `v`.`field_value` else '' end)) AS `postcode`,
max((case `f`.`id` when 55 then `v`.`field_value` else '' end)) AS `plaats`,
max((case `f`.`id` when 26 then `v`.`field_value` else '' end)) AS `telthuis`,
max((case `f`.`id` when 27 then `v`.`field_value` else '' end)) AS `telmir`,
max((case `f`.`id` when 28 then `v`.`field_value` else '' end)) AS `gsmdeelnemer`,
max((case `f`.`id` when 29 then `v`.`field_value` else '' end)) AS `gsmpapa`,
max((case `f`.`id` when 56 then `v`.`field_value` else '' end)) AS `gsmmama`,
max((case `f`.`id` when 30 then `v`.`field_value` else '' end)) AS `graad`,
max((case `f`.`id` when 88 then `v`.`field_value` else '' end)) AS `bestelling`,
max((case `f`.`id` when 34 then `v`.`field_value` else '' end)) AS `eigendom`,
max((case `f`.`id` when 57 then `v`.`field_value` else '' end)) AS `zodiac`,
max((case `f`.`id` when 42 then `v`.`field_value` else '' end)) AS `tshirt`,
max((case `f`.`id` when 39 then `v`.`field_value` else '' end)) AS `helpdag`,
max((case `f`.`id` when 40 then `v`.`field_value` else '' end)) AS `helpinfo`,
max((case `f`.`id` when 36 then `v`.`field_value` else '' end)) AS `vervoerjanee`,
max((case `f`.`id` when 37 then `v`.`field_value` else '' end)) AS `vervoerinfo`
from ((((`dat_eb_field_values` `v` join `dat_eb_registrants` `r` on((`v`.`registrant_id` = `r`.`id`)))
join `dat_eb_fields` `f` on((`v`.`field_id` = `f`.`id`)))
join `dat_eb_events` `e` on((`r`.`event_id` = `e`.`id`)))
join `dat_eb_event_categories` `ec` on((`ec`.`event_id` = `e`.`id`)))
where ((`ec`.`category_id` = 4) and (`e`.`published` = 1))
SET $rowname=$newvalue WHERE transaction_id=$transid
Normally this query uses SELECT as the first argument instead of UPDATE.
The last line was also added by me.
$rowname, $newvalue and $transid are all defined and it geives me the following error:
Not unique table/alias: 'first_name'.
Thanks in advance, Laurent
A:
The syntax for UPDATE clause is something like this
UPDATE table JOIN table1 ON table.field = table1.field SET table.field2 = 'value' WHERE table.field3 = 'value2'
You don't provide any fields to select as UPDATE clause does not select anything. So, you should remove the fields from SELECT clause and add the WHERE pats after SET.
UPDATE
((((`dat_eb_field_values` `v` join `dat_eb_registrants` `r` on((`v`.`registrant_id` = `r`.`id`)))
join `dat_eb_fields` `f` on((`v`.`field_id` = `f`.`id`)))
join `dat_eb_events` `e` on((`r`.`event_id` = `e`.`id`)))
join `dat_eb_event_categories` `ec` on((`ec`.`event_id` = `e`.`id`)))
SET $rowname=$newvalue
WHERE ((`ec`.`category_id` = 4) and (`e`.`published` = 1)) AND transaction_id=$transid
|
[
"stackoverflow",
"0031965034.txt"
] | Q:
Reading TCP raw data and send it to ActiveMQ
I want to write an application that reads tracking data from fixed unit controllers that send bytecode and process the data then write to a database. I want to use grails 3.0.4, ActiveMQ, Apache Camel. If I send the data from the controllers straight to ActiveMQ I get a DataType Error and suggestions where that I should use apache camel to receive and then route the messages.
I do know know how to setup apache camel in a grails project. Can anyone help with the steps that are needed to setup Apache Camel to read raw data from a tcp in grails 3.
A:
This is how I implemented my solution:
In build.gradle under dependencies add the following dependencies depending on the components you want to use as follows.
runtime "org.apache.camel:camel-core:2.15.3" runtime "org.apache.camel:camel-groovy:2.15.3" runtime "org.apache.camel:camel-stream:2.15.3" //runtime "org.apache.camel:camel-netty:2.15.3" runtime "org.apache.camel:camel-netty4:2.15.3" runtime "org.apache.camel:camel-spring:2.15.3" runtime "org.apache.camel:camel-jms:2.15.3" runtime "org.apache.activemq:activemq-camel:5.11.1" runtime "org.apache.activemq:activemq-pool:5.11.1"
Create a route that extends RouteBuilder as follows:
class TrackingMessageRoute extends RouteBuilder { def grailsApplication
@Override
void configure() {
def config = grailsApplication?.config
//from('netty4:tcp://192.168.254.3:553?sync=true&decoders=#decoders&encoder=#encoder').to('activemq:queue:Mimacs.Tracking.Queue')
from('netty4:tcp://192.168.254.3:553?serverInitializerFactory=#sif&keepAlive=true&sync=true&allowDefaultCodec=false').to('activemq:queue:Mimacs.Tracking.Queue')
from('activemq:queue:Mimacs.Tracking.Queue').bean(MimacsMessageListener.class)
}
}
Configure a Camel Context in BootStrap.groovy. You can use SpringBeans in resources.groovy if you want
CamelContext camelContext = new DefaultCamelContext(registry) camelContext.addComponent("activemq", ActiveMQComponent.activeMQComponent("failover:tcp://localhost:61616")) camelContext.addRoutes new TrackingMessageRoute() camelContext.start()
NB. I left out certains part of code that do not affect this answer. If you have these then you ar good to go.
|
[
"es.stackoverflow",
"0000196371.txt"
] | Q:
`if` con un boolean que no actua segun la documentacion
Estoy trabajando contra un Active Directory y la respuesta del servidor es un boolean. Y siempre, siempre, entra en la parte "true" del if.
He hecho debug devuelve false haya ido bien o mal la validación contra el Active Directory.
Siendo que el resultado es false, ¿no debería ir al else?
La parte de mi código:
if(callLDAP(internalVO));//este metodo devuelve un boolean
System.out.println("Entra en el true");
}else{
System.out.println("Entra en el false");
}
El codigo de callLDAP es esto básicamente:
private static boolean callLDAP(InternalDoLoginVO internalVO){
boolean status = false;
String LDAPServer = "servidor";
String LDAPPort = "puerto";
String LDAPDomain = "dominio";
String LDAPUser = internalVO.getUser();
String LDAPassword = internalVO.getPass();
LDAPServer LDAP = new LDAPServer(LDAPServer, LDAPPort, LDAPDomain);
LDAP.setCredentials(LDAPUser, LDAPassword);
status = LDAP.doLogin();//haciendo debug esta variable es false
return status;
}
A:
Te falta una llave en el if. Tienes un punto y coma en su lugar
if(callLDAP(internalVO)){//este metodo devuelve un boolean
System.out.println("Entra en el true");
}else{
System.out.println("Entra en el false");
}
|
[
"drupal.stackexchange",
"0000075974.txt"
] | Q:
Inserting PDF files via the Image icon in ckeditor. Is there a better way?
I would like to insert inline files throughout the text editor, without having to attach them all at the bottom of the page. I figured out that I can upload them via the image icon, remove the blank image, and then insert the link by browsing to the file I just uploaded. But surely there is a better way?
Can anyone share?
A:
The canonical "Drupal way" is to keep files in file fields. You are free not to display them in your theme for readers and only keep links in body. Having them explicitly linked to a node has some advantages: you can keep track if files are used or should be deleted, you can display them in views, in search you can possibly add "with attachment" option and so on.
You can write a CKEditor plugin - copy image uploading one, change output from <img src=" to <a href=" and you have what you wanted. It's what you want, but be careful, you might regret it in the future if you'll ever need that node-file relation.
|
[
"english.stackexchange",
"0000072672.txt"
] | Q:
What do you call someone who likes variety?
I don't mean a variety in a certain field or area like food, but in general. I'm developing an iOS quiz app with different sections to be quizzed on. For example, there is a math quiz, a history quiz, a grammar quiz, a literature quiz, a history quiz, etc. One game center achievement is to have tried every quiz. I want the game center achievement title to be something like "diverse interests" except as a single word.
A:
We don't really have enough context, but an adventurous [personality type] is one who displays curiosity, interest, novelty-seeking, openness to experience.
There's also neophile (a personality type characterized by a strong affinity for novelty), but that's something of a "cult/jargon" neologism with rather more limited currency.
EDIT: Now the question has been edited to give more context, I suggest...
intrepid (characterized by resolute fearlessness, fortitude, and endurance)
...which seems to me a far more appropriate "honorific" for OP's category of game players.
EDIT2: polymath (a person whose expertise spans a significant number of different subject areas)
A:
Consider venturesome ("Bold; willing to take risks; adventurous"), mercurial ("Volatile; erratic; unstable; flighty; fickle or changeable in temperament" or "Lively; clever; sprightly; animated; quick-witted"), impetuous ("Making arbitrary decisions, especially in an impulsive and forceful manner") and some of their synonyms.
Note, with question as modified, perhaps only venturesome is relevant. For titles of an achievement, consider enthusiast, fanatic, experienced, well-rounded.
|
[
"math.stackexchange",
"0002028083.txt"
] | Q:
Is there a simpler way to find an inverse of a congruence?
In order to find an inverse of a congruence, do we have to go through Euclid’s algorithm and do back substitution?
Here is an example to find an inverse of 9 modulo 23.
A:
There are many ways to compute modular inverses that are often simpler for smaller numbers, e.g. below I use Gauss's algorithm a few ways. The basic idea is to scale the top and bottom to obtain a $\rm\color{#c00}{smaller}$ denominator, then repeat, till the bottom exactly divides the top (or $ $ top $\!\pm\!$ modulus)
${\rm mod}\ 23\!:\,\ \dfrac{1}9\equiv \dfrac{3}{27}\equiv \dfrac{-20}{\color{#c00}4}\equiv -5$
${\rm mod}\ 23\!:\,\ \dfrac{1}9\equiv \dfrac{2}{18}\equiv \dfrac{25}{\color{#c00}{-5}}\equiv -5$
${\rm mod}\ 23\!:\,\ \dfrac{1}3\equiv \dfrac{24}3\equiv 8\,\Rightarrow\,\dfrac{1}9\equiv 8^2\equiv -5 $
Beware $\ $ Modular fraction arithmetic is well-defined only for fractions with denominator coprime to the modulus. See here for further discussion.
A:
EDIT: remembered the name of the thing I was talking about: the primitive roots
My two favorite methods are guessing and brute-forcing. Together with Euclid's Algorithm, these are the most pratical ways I know of calculating inverses.
(As I see now from other answers there are many inventive representations and ways to compute just a couple of useful methods.)
Unless one knows a primitive root, in which case it generates all invertible elements and therefore inverting one is just check what is the power of the primitive root that cancels it.
|
[
"stackoverflow",
"0047748733.txt"
] | Q:
Angular 5 - Reactive forms doesn't validate form on submit
I have a simple form as below:
some.component.html
<form class="example-form" novalidate (ngSubmit)="onSubmit()" autocomplete="off" [formGroup]="testform">
<input type="text" formControlName="name" class="form-control" placeholder="Enter name" required/>
<app-show-errors [control]="claimform.controls.name"></app-show-errors>
<button type="submit" (click)="onSubmit()">Next</button>
</form>
some.component.ts
ngOnInit() {
this.testform= new FormGroup({
name: new FormControl('', { validators: Validators.required})
}, {updateOn: 'submit'});
}
onSubmit() {
if (this.testform.valid) {
alert('saving data');
} else {
this._validationService.validateAllFormFields(this.testform);
}
}
validationService.ts
validateAllFormFields(formGroup: FormGroup) {
Object.keys(formGroup.controls).forEach(field => {
const control = formGroup.get(field);
if (control instanceof FormControl) {
control.markAsTouched({ onlySelf: true });
} else if (control instanceof FormGroup) {
this.validateAllFormFields(control);
}
});
}
Reference
Problem
The form will validate on submit if left blank, but even after filling the value when I check this.testform.valid it returns false. But if I remove updateOn:'submit' on form then it validates on blur of input control and when value is entered it validates form return true. Not sure if updateOn is working fine or not or whether I've implemented this in a proper way. Could someone point me in the right direction.
A:
in your HTML you have two calls to onSubmit() function, from submit button:
<button type="submit" (click)="onSubmit()">Next</button>
and from the form:
<form class="example-form"
ovalidate
(ngSubmit)="onSubmit()"
autocomplete="off"
[formGroup]="testform">
The first call to be triggered is the button's trigger, which actually does nothing in terms of updating your reactive form, since you set FormGroup's option to {updateOn: 'submit'}. The second call to be triggered is the form's trigger, which does actual form update.
Here is FormGroup directive config:
@Directive({
selector: '[formGroup]',
providers: [formDirectiveProvider],
host: {'(submit)': 'onSubmit($event)', '(reset)': 'onReset()'},
exportAs: 'ngForm'
})
as we can see in host property DOM form's submit (triggered by hitting ENTER while focused within form or clicking form's submit button) will call onSubmit() function:
onSubmit($event: Event): boolean {
(this as{submitted: boolean}).submitted = true;
syncPendingControls(this.form, this.directives);
this.ngSubmit.emit($event);
return false;
}
which then will call syncPendingControls() function:
export function syncPendingControls(form: FormGroup, directives: NgControl[]): void {
form._syncPendingControls();
directives.forEach(dir => {
const control = dir.control as FormControl;
if (control.updateOn === 'submit' && control._pendingChange) {
dir.viewToModelUpdate(control._pendingValue);
control._pendingChange = false;
}
});
}
which updates a model at last.
So, in your case, just remove (click)="onSubmit()" from the submit button:
<button type="submit">Next</button>
also you do not need required DOM element property on your input, since you set it using Reactive Forms API validators: Validators.required and since you set your form to novalidate which cancels HTML5 form validation.
|
[
"stackoverflow",
"0019745063.txt"
] | Q:
How to take screenshot of a user defined rectangular area in cocos2d
I need to take the screenshot in my cocos2d application. I've searched a lot, even in stack overflow. Then I found the following code:
+(UIImage*) screenshotWithStartNode:(CCNode*)stNode
{
[CCDirector sharedDirector].nextDeltaTimeZero = YES;
CGSize winSize = [[CCDirector sharedDirector] winSize];
CCRenderTexture* renTxture =
[CCRenderTexture renderTextureWithWidth:winSize.width
height:winSize.height];
[renTxture begin];
[stNode visit];
[renTxture end];
return [renTxture getUIImage];
}
Now,
Problem: The above code gives me the entire screenshot. But I am in need of the screenshot of a custom are, such as, within a CGRect(50,50,100,200).
Can anyone please help me..? Thanks...
A:
Wow... found out what I need. I've changed the above method like:
-(UIImage*) screenshotWithStartNode:(CCNode*)startNode
{
[CCDirector sharedDirector].nextDeltaTimeZero = YES;
CGSize winSize = [CCDirector sharedDirector].winSize;
CCRenderTexture* rtx =
[CCRenderTexture renderTextureWithWidth:winSize.width
height:winSize.height];
[rtx begin];
[startNode visit];
[rtx end];
UIImage *tempImage = [rtx getUIImage];
CGRect imageBoundary = CGRectMake(100, 100, 300, 300);
UIGraphicsBeginImageContext(imageBoundary.size);
CGContextRef context = UIGraphicsGetCurrentContext();
// translated rectangle for drawing sub image
CGRect drawRect = CGRectMake(-imageBoundary.origin.x, -imageBoundary.origin.y, tempImage.size.width, tempImage.size.height);
// clip to the bounds of the image context
CGContextClipToRect(context, CGRectMake(0, 0, imageBoundary.size.width, imageBoundary.size.height));
// draw image
[tempImage drawInRect:drawRect];
// grab image
UIImage* subImage = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
return subImage;
}
|
[
"computergraphics.stackexchange",
"0000001790.txt"
] | Q:
What does "6-separating" and "26-separating" voxelization mean?
I was reading this paper about Voxelpipe, a voxelization library from NVIDIA and I found on section 2 Voxelization the terms 6-separating and 26-separating
I found this website that tries to explain the basic ideas on voxelization but it wasn't very much helpful understanding the terms mentioned.
Can anybody explain or point out to some other resource that can help me understand?
A:
The terms have to do with the "thickness" of the voxelization. I'll illustrate with the help of a diagram about 2D line rasterization (from this unrelated question).
On the right is the typical line rasterization: the algorithm finds the one pixel nearest the line within each row (or column, depending on slope). This produces what we usually think of as a "1-pixel-thick" line. On the left is a conservative rasterization, which finds every pixel whose rectangle is touched by the line, and it produces a thicker line.
6-separating voxelization is like the thin line on the right, and 26-separating is like the thick line on the left, but in 3D. If you imagine the line is actually a triangle viewed on-edge, this is analogous to what the voxelization would look like.
Different types of voxelization may be better depending on what you're going to do with the voxelized data later. If you're using the voxels as a spatial hierarchy to find triangles that intersect a given region, you probably want the thick voxelization, as it's conservative. The thick voxelization might also be preferable for ray-marching, as the thin voxelization could be missed by a diagonal ray. On the other hand, the thin voxelization is a more faithful representation of the original surface, which is probably better for visibility tests, collision detection, fluid simulation, and suchlike.
The "n-separating" terminology is a bit unfortunate, but here's what it's getting at. Imagine you're doing a 3D flood-fill in the voxel grid, but in the flood-fill you only look at the 6 direct neighbors of each voxel (±1 step along each axis). Then the "6-separating" (thin) voxelization will stop the flood-fill: it suffices to separate the two sides of the surface, if only 6 neighbors are considered. On the other hand, suppose your flood-fill was allowed to go to diagonal neighbors as well—26 neighbors in all (3×3×3 neighborhood of voxels). Then the 6-separating voxelization wouldn't stop the flood fill, but the 26-separating (thick) one would.
|
[
"stackoverflow",
"0027958285.txt"
] | Q:
Why does the device vibrate from an Activity, but not from within a Class (file)?
I want my app to vibrate the device using my app's custom vibration pattern. I can do this from MainActivity, or any Activity, but I don't know why it isn't working from within a Java class (SmsReceiver.java).
I thought that if I use ...context.getApplicationContext.getSystemService(Context.VIBRATOR_SERVICE); it would get the MainActivity context and thus would be kind of like I was in the MainActivity and it would vibrate. But nope. It doesn't vibrate from the Receiver class.
How do I vibrate the phone from the SmsReceiver.java class?
SmsReceiver.java:
package com.app.name.app;
import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.os.Bundle;
import android.os.Vibrator;
import android.telephony.SmsMessage;
import android.util.Log;
import android.widget.Toast;
public class SmsReceiver extends BroadcastReceiver {
private static final String SMS_RECEIVED = "android.provider.Telephony.SMS_RECEIVED";
@Override
public void onReceive(Context context, Intent intent) {
if (intent.getAction().equals(SMS_RECEIVED)) {
Bundle bundle = intent.getExtras();
if (bundle != null) {
// get sms objects
Object[] pdus = (Object[]) bundle.get("pdus");
if (pdus.length == 0) {
return;
}
// large message might be broken into many
SmsMessage[] messages = new SmsMessage[pdus.length];
StringBuilder sb = new StringBuilder();
for (int i = 0; i < pdus.length; i++) {
messages[i] = SmsMessage.createFromPdu((byte[]) pdus[i]);
sb.append(messages[i].getMessageBody());
}
String sender = messages[0].getOriginatingAddress();
Log.d("SNDR", sender);
String message = sb.toString();
// prevent any other broadcast receivers from receiving broadcast
abortBroadcast();
if(!message.isEmpty())
{
if(message == "!")
{
Vibrator v = (Vibrator)context.getApplicationContext().getSystemService(Context.VIBRATOR_SERVICE);
v.cancel();
long[] longs = { 0, 75, 15, 100, 15, 100, 15, 75, 15 };
v.vibrate(longs, -1);
}
}
Toast.makeText(context, message, Toast.LENGTH_SHORT).show();
}
}
}
}
MainActivity.java, onButtonClick:
switch(id)
{
case R.id.action_search:
Vibrator v = (Vibrator)getSystemService(Context.VIBRATOR_SERVICE);
long[] longs = { 0, 75, 15, 100, 15, 100, 15, 75, 15 };
v.vibrate(longs, -1);
break;
case R.id.action_settings:
break;
}
This related question does not solve this issue.
A:
I don't believe there's any restriction on using the Vibrator service from a BroadcastReceiver. I think your problem has to do with your String comparison. You should be using String#equals() to test for String equality, not ==.
if(message.equals("!"))
|
[
"stackoverflow",
"0040488827.txt"
] | Q:
Add textblock text to favorite list on button click
I have two pages: the first is mainpage.xaml and the second is favoriteslist.xaml.
In mainpage.xaml I have a text block, which shows some dynamic text automatically.
And I have a button also on mainpage.xaml.
From which I want when I click on that button, text appears on text block should go to favorite list in favoriteslist.xaml page.
If text already favorite, which text appears on text block should be removed from favorite list on button click.
So finally I need help to implement this functionality textblock which shows dynamically already created but I only need to know how to develop add to favorite functionality.
Textblock:
<TextBlock x:Name="StringTextBlock" Text="" Margin="9,-7,0,0" Style="{StaticResource PhoneTextTitle1Style}" />
Button:
<Button Grid.Row="2" x:Name="AddToFavoritesButton"
Content="Add" Style="{StaticResource ButtonStyle2}" Margin="2"
Click="AddToFavoritesButton_Click"/>
C#
private void AddToFavoritesButton_Click(object sender, RoutedEventArgs e)
{
}
Listbox:
<ListBox x:Name="FavoriteListBox" />
A:
I would use IsolatedStorageSettings to store the list and compare the dynamic text to the list in the isolatedstoragesettings upon button click. Then on FavouritesList page, set itemsource of the listbox to the list in IsolatedStorageSettings.So here are the steps to be followed:
1. Create a model/class to set the dynamic text being shown on the text block
public class favourites
{
public string myText { get; set; }
}
2. In the button click event on MainPage.xaml.cs, first set the dynamic text (where ever you are getting it from) to the text block if you need to and then create the list and/or compare
private void AddToFavoritesButton_Click(object sender, RoutedEventArgs e)
{
//your dynamic text set to textblock
StringTextBlock.Text = myDynamicText;
//Set value of your text to member variable of the model/class
favourites f = new favourites();
f.myText = myDynamicText;
IsolatedStorageSettings settings = IsolatedStorageSettings.ApplicationSettings;
/*Check if "FavouritesList" key is present in IsolatedStorageSettings
which means already a list had been added. If yes, retrieve the
list, compare each item with your dynamic text, add or remove
accordingly and replace the new list in IsolatedStorageSettings
with same key. */
if (settings.Contains("FavouritesList"))
{
List<favourites> l = (List<favourites>)settings["FavouritesList"];
for(int i = 0; i <= l.Count()-1; i++)
{
if (l[i].Equals(myDynamicText))
{
l.RemoveAt(i);
settings["FavouritesList"] = l;
}
else
{
l.Add(f);
settings["FavouritesList"] = l;
}
}
}
//If no key in IsolatedStorageSettings means no data has been added
//in list and IsolatedStorageSettings. So add new data
else
{
List<favourites> l = new List<favourites>();
l.Add(f);
settings["FavouritesList"] = l;
}
settings.Save();
}
Now all that is left is show the always updated list in the FavouritesList Page. I added a 'NoData' textblock that should be visible when there is nothing in the list. Else the list will be displayed.
In FavouritesList.xaml
<ListBox x:Name="FavoriteListBox" Visibility="Collapsed">
<ListBox.ItemTemplate>
<DataTemplate>
<TextBlock Text="{Binding myText}"/>
</DataTemplate>
</ListBox.ItemTemplate>
</ListBox>
<TextBlock Name="NoData"
Text="No Data"
Visibility="Collapsed"
Width="50"
Height="50"/>
In FavouritesList.xaml.cs
IsolatedStorageSettings settings = IsolatedStorageSettings.ApplicationSettings;
if (settings.Contains("FavouritesList"))
{
List<favourites> l = (List<favourites>)settings["FavouritesList"];
if(l.Count!= 0)
{
NoData.Visibility = System.Windows.Visibility.Collapsed;
FavoriteListBox.Visibility = System.Windows.Visibility.Visible;
FavoriteListBox.ItemsSource = l;
}
}
else
{
FavoriteListBox.Visibility = System.Windows.Visibility.Collapsed;
NoData.Visibility = System.Windows.Visibility.Visible;
}
I have not tested this but should definitely work. Hope it helps!
|
[
"stackoverflow",
"0004332755.txt"
] | Q:
How to read a String (file) to array in java
Suppose there is a file named as SUN.txt
File contains : a,b,dd,ss,
I want to make dynamic array depending upon the number of attributes in file.
If ther is a char after comma then array will be of 0-4 i.e of length 5.
In the above mentioned case there is no Char which returns 0-3 Array of length 4. I want to read the NULL after comma too.
How do i do that?
Sundhas
A:
You should think about
Reading the file into a String
Splitting the file by separator ','
Using a list for adding the characters and convert the list to an array, when the list is filled
A:
As Markus said, you want to do something like this..
//Create a buffred reader so that you can read in the file
BufferedReader reader = new BufferedReader(new FileReader(new File(
"\\SUN.txt")));
//The StringBuffer will be used to create a string if your file has multiple lines
StringBuffer sb = new StringBuffer();
String line;
while((line = reader.readLine())!= null)
{
sb.append(line);
}
//We now split the line on the "," to get a string array of the values
String [] store = sb.toString().split(",");
I do not quite understand why you would want the NULL after the comma? I am assuming that you mean after the last comma you would like that to be null in your array? I do not quite see the point in that but that is not what the question is.
If that is the case you wont read in a NULL, if after the comma there was a space, you could read that in.
If you would like a NULL you would have to add it in yourself at the end so you could do something like
//Create a buffred reader so that you can read in the file
BufferedReader reader = new BufferedReader(new FileReader(new File(
"\\SUN.txt")));
//Use an arraylist to store the values including nulls
ArrayList<String> store = new ArrayList<String>();
String line;
while((line = reader.readLine())!= null)
{
String [] splitLine = line.split(",");
for(String x : splitLine)
{
store.add(line);
}
//This tests to see if the last character of the line is , and will add a null into the array list
if(line.endsWith(","))
store.add(null);
}
String [] storeWithNull = store.toArray();
|
[
"stackoverflow",
"0048060417.txt"
] | Q:
vb.net XML (SVG) xlink:href=
I am trying to make a .svg file using vb.net and I need to add a company logo.
I am using the following code to add the image element:
'Add logo
.WriteStartElement("image")
.WriteAttributeString("width", "100")
.WriteAttributeString("height", "100")
.WriteAttributeString("xlink", "href", "data:img/png;base64, string of company logo")
.WriteAttributeString("x", "200")
.WriteAttributeString("y", "200")
But I end up with this in my XML file:
<image width="100" height="100" p4:xlink="data:img/png;base64, string of company logo" />
But I want to end up with:
<image width="100" height="100" xlink:href="data:img/png;base64, string of company logo" />
What am I doing wrong? and what do I need to change in my code to get the required result in my .svg file?
A:
I fixed my problem by changing this line:
.WriteAttributeString("xlink", "href", "data:img/png;base64, string of company logo")
to this
.WriteAttributeString("xlink", "href", Nothing, "data:img/png;base64, string of company logo")
not sure why this works and my earlier solution didn....
|
[
"math.stackexchange",
"0001347509.txt"
] | Q:
Determinant Question.
Show that if $A=\begin{bmatrix}a & b\\c & d\end{bmatrix}$, then
$\det(A)=\frac{1}{2}\det\left(\begin{bmatrix}1 & 1\\tr(A^2) & (tr(A))^2\end{bmatrix}\right)$.
I tried finding the determinant using the formula but it didn't come out to be the same as when I found determinant using cofactor expansion.
A:
We have that
$$det(A) = ad-bc$$
$$A^{2} = \begin{bmatrix} a^{2} + bc & ab + bd \\ ca + dc & cb + d^{2}\end{bmatrix}$$
Then
\begin{align*}
\frac{1}{2} \cdot det(\begin{bmatrix}1 & 1\\tr(A^2) & (tr(A))^2\end{bmatrix}) &=\frac{1}{2} \cdot det(\begin{bmatrix}1 & 1\\a^{2} + 2bc + d^{2} & (a+d)^{2}\end{bmatrix}) \\
&= \frac{1}{2}(a^{2} + 2ad + d^{2} - a^{2} - 2bc - d^{2}) \\
&= ad - bc
\end{align*}
as required.
|
[
"stackoverflow",
"0009916025.txt"
] | Q:
GAE initialization recommended practice
I've a Java GAE app that should clear the memcache whenever I deploy a new version of the app. I'm using static initializer, i.e.
static {
MemcacheServiceFactory.getMemcacheService().clearAll();
}
However, that would clear the memcache as well whenever a new instance is started, which is not desired behavior.
What is the proper way to execute initialization code?
TIA
A:
I create my memcache keys using a factory and they always get appended with the version number of my app so when i upload a new version, the keys are new I forget about the old cached values, which will go away on their own.
I also have a servlet defined in web.xml with a security constraint for admin only, then I browse to it's URL (/admin/example) manually after an upgrade - logging in as as admin. The servlet has my run once code in it to kick off any tasks for upgrading store data and purging the cache.
<security-constraint>
<web-resource-collection>
<url-pattern>/admin/*</url-pattern>
</web-resource-collection>
<auth-constraint>
<role-name>admin</role-name>
</auth-constraint>
</security-constraint>
|
[
"math.stackexchange",
"0001346597.txt"
] | Q:
Evaluate the following Integration--
Evaluate the following Integration $$\int \frac{\cos^9 x}{\sin^3 x + \cos^3 x} \,dx$$
I tried, but this problem is very difficult to me. any help?
A:
Hint
As suggested by Paramanand Singh in a comment, change variable $x=\tan^{-1}(t)$. This makes $$\int \frac{\cos^9 (x)}{\sin^3 (x) + \cos^3 (x)} \,dx=\int\frac{dt}{\left(t^2+1\right)^4 \left(t^3+1\right)}$$ Now, using partial fraction decomposition the new integrand becomes $$\frac{-11 t-5}{16 \left(t^2+1\right)}+\frac{2 t-1}{3 \left(t^2-t+1\right)}-\frac{3
(t-1)}{8 \left(t^2+1\right)^2}+\frac{t+3}{4 \left(t^2+1\right)^3}+\frac{t+1}{2
\left(t^2+1\right)^4}+\frac{1}{48 (t+1)}$$ which is not too complex.
I am sure that you can take from here.
Edit
For the first term $$\frac{-11 t-5}{16 \left(t^2+1\right)}=-\frac{11}{32}\frac{2t}{t^2+1}-\frac{5}{16}\frac{1}{t^2+1}=-\frac{11}{32}\frac{(t^2+1)'}{t^2+1}-\frac{5}{16}\frac{1}{t^2+1}$$ For the second term $$\frac{2 t-1}{3 \left(t^2-t+1\right)}=\frac{1}3 \frac{2 t-1}{t^2-t+1}=\frac{1}3 \frac{(t^2-t+1)'}{t^2-t+1}$$
|
[
"stackoverflow",
"0012946522.txt"
] | Q:
How can I count the times an HTML5 video is played
I'm developing a site that shows videos from youtube, and I'm interested in knowing how many times each video has been played from my web. Youtube views doesn't count, just the views from my web. I've found this approach for audio:
Tracking how many times an HTML5 audio element is played?
Can I use the same approach for videos? Someone has done this? How? I have found a similar question:
Tracking the number of times a video was played
But the answer is not satisfying for me, I need to do it without a third party service, if it is possible, of course.
A:
I used the example from https://developer.mozilla.org/en-US/docs/DOM/Media_events
I adapted it to do what I wanted:
var v = document.getElementsByTagName("video")[0];
v.addEventListener("ended", function() {
alert('Video has been viewed!');
}, true);
|
[
"spanish.stackexchange",
"0000028611.txt"
] | Q:
¿Por qué inflamable y no flamable?
En México, la gente a veces usa el adjetivo flamable en lugar del "correcto" inflamable para referirse a algo que puede encenderse con facilidad. Eso me dejó pensando, ¿por qué, en español, decimos inflamable?
Sobre todo considerando que el prefijo in- tiene las siguientes definiciones en el DLE:
in-1. 1. pref. Suele significar 'adentro' o 'al interior'. Infiltrar, inseminación, implantar, irrumpir.
in-2. 1. pref. Indica negación o privación. Inacabable, incomunicar, inacción, impaciencia, ilegal, irreal.
A:
En la propia pregunta aparece la respuesta. La primera acepción del prefijo "in-" es la clave.
En efecto, en este caso "in-" no es un prefijo de negación, sino que hace referencia a la preposición "en", y proviene del latín. El significado sería, como apunta guifa,
en-llamas-able.
Es decir, capaz de ponerse en llamas, y por tanto que puede arder. Por el contrario, "flamable" sería algo como "capaz de convertirse en una llama", que no es lo mismo.
PD: Enviar al Dr. Nick Riviera de los Simpsons, en clara alusión, jaja https://www.youtube.com/watch?v=efDYvtj2Rlo
Fuente: http://etimologias.dechile.net/?inflamable
A:
Viene del verbo inflamar, del latín inflammare que significaba poner en llamas. Flammare existía en latín también, pero significaba generalmente arder, o estar en llamas. Inflamar es el acto de hacer que otra cosa arda, y el sufijo V.-able/-ible significa capaz de ser V.-ado/-ido. Así, algo inflamable es algo capaz de ser puesto en llamas (u hoy diríamos capaz de ser encendido).
|
[
"english.stackexchange",
"0000022042.txt"
] | Q:
What are synonyms of the word "metadata"?
Metadata is "data about data". Are there other words with similar meaning?
A:
Metadata has no meaningful synonym in software development; it's the abstract term to refer to data that describe the context of another value. The words object, type, attribute, property, aspect, and schema all refer to metadata in some context. The elements of a web page, for example, are collectively referred to as the Document Object Model, or DOM for short. The DOM contains the order, type, reference name, display name, and value of each element in the page. Or, more generally, it's the metadata for a web page.
So I'm thinking what you really want is a more specific term than metadata, rather than a synonym for it.
A:
I agree with all the answerers that metadata is the more general and useful terms and all other options are more restrictive or context-sensitive.
Other possible (but less general) terms not already proposed, and sometimes found in software, the general idea being that the collection of metadata on an object "x" can allow identification/disambiguation/research of "x" :
Known facts about "x"
General facts about "x"
Information resources on "x"
Identity card of "x"
Pedigree of "x"
Description of "x"
and a dozen more variants.
One can also remark that metadata is a bit barbaric. Didactic close-equivalent words would be
prologos
metalogos
perilogos
epilogos
with the exact choice depending of the relation between the information and the subject of it. For instance peri is really "about" but in a more concrete way (think perimeter, delimiting the object), than meta, which has more often the meaning of "information of a higher level, of another kind, with precedence or pre-existence".
|
[
"stackoverflow",
"0050915593.txt"
] | Q:
Flask rendering templates from another folder
I have a simple flask app with only an index.html page (so far), it's located in a folder with a bunch of javascript and CSS, which makes it a bit difficult to render.
I tried listing the file path for my HTML, however, it gives an internal server error, when I open the browser. Should I instead declare the path as a variable and pass that in?
I'm on Linux Ubuntu 16.04 btw.
here is my sample code:
from flask import Flask, render_template
app = Flask(__name__)
@app.route("/")
@app.route("/home")
def home():
return render_template('/frontend/index.html')
here is how my directory is listed
--flaskwebsite
----routes.py
----routes.pyc
----templates
------frontend(other folders, javascript files etc)
------index.html
A:
If Im seeing your folder structure correctly.
'templates/frontend/index.html'
Also you should have a separate template folder and a separate folder for static files such as css, js, pictures, and fonts.
|
[
"stackoverflow",
"0028296794.txt"
] | Q:
Query CouchDB with multiple keys for multiple properties
I'm using couch db to store subscription documents. While performing queries, I want to be able to query on multiple properties and also use an "IN" clause. For example, I have a subscriptionStatus property which can have multiple values (Active, Failed, In_Progress etc.) and subscriptions also have a customerID.
How can I create a query for all subscriptions where customerID = "JD212S" AND subscriptionStatus IN ["Active", "In_Progress"]
Essentially show me active and in progress subscriptions for a particular customer.
I looked at combinations of views, multiple keys etc but I was not able to do this (or I've misunderstood the docs).
I've had a look at a number of Stack Overflow Q/A and CouchDB docs for this but seem to find options only for a single property at a time.
A:
it does look list a duplicate, but in your context you would create a view return multiple keys then when executing that view, like the link here states, pass in your multi-key options
// view foo/bar
var view = function(doc) {
doc.emit([doc.customerId, doc.subscriptionStatus]);
}
db.view('foo/bar', { keys: [['JD212S','Active'],
['JD212S','In_Progress']], include_docs: true });
|
[
"stackoverflow",
"0012133290.txt"
] | Q:
Cannot add panel
The code I have, creates a set buttons but are vertically aligned
Now what I wanna do is add a JLabel to this panel but when I create an new JPanel, I get an error when I run it, but code doesn't give me any conflicts. And I would like to rearrange the buttons in a flowlayout if possible.
my full code:
import java.awt.*;
import javax.swing.*;
import java.awt.event.*;
public final class CharSearch extends Box {
int i = 0;
int error = 0;
static JPanel panel;
String original = "Dinosaur";
String secret = new String(new char[original.length()]).replace('\0', '-');
public CharSearch() {
super(BoxLayout.Y_AXIS);
for (char i = 'A'; i <= 'Z'; i++) {
String buttonText = new Character(i).toString();
JButton button = getButton(buttonText);
add(button);
}
JLabel label = new JLabel(secret);
JPanel panel = new JPanel();
panel.add(label);
}
public JButton getButton(final String text) {
final JButton button = new JButton(text);
button.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
if (original.indexOf(text) != -1) {
JOptionPane.showConfirmDialog(null,
"Your word does contain" + text);
} else {
JOptionPane.showConfirmDialog(null, "There is no" + text);
}
// If you want to do something with the button:
button.setText("Clicked"); // (can access button because it's
// marked as final)
}
});
return button;
}
public static void main(String[] args) {
EventQueue.invokeLater(new Runnable() {
public void run() {
JFrame frame = new JFrame();
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.add(panel);
frame.setContentPane(new CharSearch());
frame.pack();
frame.setVisible(true);
new CharSearch();
}
});
}
}
and this is the error I get when I run it
Exception is:
Exception in thread "AWT-EventQueue-0" java.lang.NullPointerException
at java.awt.Container.addImpl(Unknown Source)
at java.awt.Container.add(Unknown Source)
at javax.swing.JFrame.addImpl(Unknown Source)
at java.awt.Container.add(Unknown Source)
at org.informatica.com.CharSearch$2.run(CharSearch.java:50)
at java.awt.event.InvocationEvent.dispatch(Unknown Source)
at java.awt.EventQueue.dispatchEventImpl(Unknown Source)
at java.awt.EventQueue.access$000(Unknown Source)
at java.awt.EventQueue$1.run(Unknown Source)
at java.awt.EventQueue$1.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
at java.security.AccessControlContext$1.doIntersectionPrivilege(Unknown Source)
at java.awt.EventQueue.dispatchEvent(Unknown Source)
at java.awt.EventDispatchThread.pumpOneEventForFilters(Unknown Source)
at java.awt.EventDispatchThread.pumpEventsForFilter(Unknown Source)
at java.awt.EventDispatchThread.pumpEventsForHierarchy(Unknown Source)
at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
at java.awt.EventDispatchThread.run(Unknown Source)
A:
You are adding an undefined JPanel object to your JFrame, resulting in a NullPointerException, as is noted in the Container#add(Component) documentation.
frame.add(panel);
You must instantiate panel before adding it to your JFrame's content pane container.
A:
For the NullPointerException it's because of this line:
frame.add(panel);
While you've created a global variable panel you are not instantiating it before adding it to the frame
|
[
"stackoverflow",
"0010756130.txt"
] | Q:
How to retrieve stage from JavaFX Application Class
I am writing an application with 2 different BorderPanes, BorderPane A and BorderPane B.
The application has 2 menuitems, such that, when clicked it HAS to show BorderPane A or BorderPane B.
This is the Application class, which has the stage I want to use
public class SampleApp extends Application {
private Stage primaryStage;
public static void main(final String[] args) {
launch(args);
}
@Override
public void start(final Stage stage)
throws Exception {
final AnnotationConfigApplicationContext context = new AnnotationConfigApplicationContext(SampleAppFactory.class);
final SpringFxmlLoader loader = new SpringFxmlLoader(context);
final Parent root = (Parent) loader.load("Main.fxml", Main.class);
final Scene scene = new Scene(root, 600, 480, Color.ALICEBLUE);
this.primaryStage = stage;
scene.getStylesheets().add("fxmlapp.css");
stage.setScene(scene);
stage.show();
}
}
The Main.java Class has two BorderPanes, when the menuItem is chosen I want to show the borderpane on the Application.
Does someone knows how to show the Borderpane(set the Scene on Stage) from this method(showBorderPane)?
I'd like to retrieve the Stage and set the scene with de borderpane:
public class Main extends BorderPane implements Initializable {
@FXML
private Verbinding verbindingContent; // BORDERPANE A
@FXML
private Beheer beheerContent;// BORDERPANE A
@FXML
private MenuBar menuContent;
@Override
public void initialize(final URL url, final ResourceBundle rb) {
System.out.println(url);
menuContent.setFocusTraversable(true);
}
@FXML
private void showBorderPane(final ActionEvent event) {
final MenuItem menuItem = (MenuItem) event.getSource();
}
@FXML
private void handleCloseAction(final ActionEvent event) {
System.exit(0);
}
}
my Main.xml
<?xml version="1.0" encoding="UTF-8"?>
<?import java.lang.*?>
<?import javafx.scene.*?>
<?import javafx.scene.control.*?>
<?import javafx.scene.layout.*?>
<?import javafx.scene.shape.*?>
<?import javafx.scene.effect.*?>
<?import nl.mamaloe.tab.view.Main?>
<BorderPane xmlns:fx="http://javafx.com/fxml" fx:controller="nl.mamaloe.tab.view.Main">
<fx:define>
<fx:include source="scene/Beheer.fxml" fx:id="beheerContent" />
<!-- fx:include source="Menu.fxml" fx:id="menuContent" / -->
</fx:define>
<top>
<MenuBar fx:id="menuContent" onMouseClicked="#handleKeyInput">
<menus>
<Menu text="Systeem">
<items>
<MenuItem text="Verbinding maken" onAction="#handleVerbindingAction"/>
<SeparatorMenuItem />
<MenuItem text="Afsluiten" onAction="#handleCloseAction"/>
</items>
</Menu>
<Menu text="TAB">
<items>
<MenuItem text="Script toevoegen" onAction="#handleAboutAction"/>
<SeparatorMenuItem />
<MenuItem text="Script draaien" />
</items>
</Menu>
<Menu text="About" onAction="#handleAboutAction">
<items>
<MenuItem text="Op basis van wizard" />
</items>
</Menu>
</menus>
</MenuBar>
</top>
<center> <Label text="Add New Dock of Home" />
</center>
I've seen it is possible to do this from the start method of the application.
But I'd like to implement it in the Main.java because of structure and I am using mainly FXML to declare the GUI.
A:
When the "Main.fxml" file is loaded by FXMLLoader, a new BorderPane (defined in Main.fxml) is created. The loader also creates/initializes its controller class which is another BorderPane-derived class with its own instance. So there are two different instances of BorderPanes. Your design is a bit different from general approach though, to achieve your goal, I suggest to add a container into center in FXML file like this:
<center>
<StackPane fx:id="pane">
<children>
<Label text="Add New Dock of Home" />
</children>
</StackPane>
</center>
You can change the StackPane with any pane/layout you want.
Next make a link to it in the controller class:
@FXML
private StackPane pane;
and you should remove "extends BorderPane" because it is no sense anymore. Finally,
@FXML
private void showBorderPane(final ActionEvent event) {
final MenuItem menuItem = (MenuItem) event.getSource();
pane.getChildren().clear(); // Clear old content.
switch (menuItem.getText()) {
case "Borderpane A":
pane.getChildren().add(borderPaneA);
break;
case "Borderpane B":
pane.getChildren().add(borderPaneB);
break;
default:
pane.getChildren().add(new Label("Add New Dock of Home"));
}
}
|
[
"stackoverflow",
"0044728071.txt"
] | Q:
ClassCastException:String cannot be cast to
I have an error in my code.
logcat:
java.lang.ClassCastException: java.lang.String cannot be cast to
com.example.aymen.schoolmanager.dates
at
com.example.aymen.schoolmanager.Adapter.onBindViewHolder(Adapter.java:68)
at
com.example.aymen.schoolmanager.Adapter.onBindViewHolder(Adapter.java:20)
at
android.support.v7.widget.RecyclerView$Adapter.onBindViewHolder(RecyclerView.java:6356)
at
android.support.v7.widget.RecyclerView$Adapter.bindViewHolder(RecyclerView.java:6389)
at
android.support.v7.widget.RecyclerView$Recycler.tryBindViewHolderByDeadline(RecyclerView.java:5335)
at
android.support.v7.widget.RecyclerView$Recycler.tryGetViewHolderForPositionByDeadline(RecyclerView.java:5598)
at
android.support.v7.widget.RecyclerView$Recycler.getViewForPosition(RecyclerView.java:5440)
at
android.support.v7.widget.RecyclerView$Recycler.getViewForPosition(RecyclerView.java:5436)
at
android.support.v7.widget.LinearLayoutManager$LayoutState.next(LinearLayoutManager.java:2224)
at
android.support.v7.widget.LinearLayoutManager.layoutChunk(LinearLayoutManager.java:1551)
at
android.support.v7.widget.LinearLayoutManager.fill(LinearLayoutManager.java:1511)
at
android.support.v7.widget.LinearLayoutManager.onLayoutChildren(LinearLayoutManager.java:595)
at
android.support.v7.widget.RecyclerView.dispatchLayoutStep2(RecyclerView.java:3583)
at
android.support.v7.widget.RecyclerView.dispatchLayout(RecyclerView.java:3312)
at
android.support.v7.widget.RecyclerView.onLayout(RecyclerView.java:3844)
at android.view.View.layout(View.java:17637)
at android.view.ViewGroup.layout(ViewGroup.java:5575)
at android.widget.RelativeLayout.onLayout(RelativeLayout.java:1079)
at android.view.View.layout(View.java:17637)
at android.view.ViewGroup.layout(ViewGroup.java:5575)
at android.support.v4.view.ViewPager.onLayout(ViewPager.java:1795)
at android.view.View.layout(View.java:17637)
at android.view.ViewGroup.layout(ViewGroup.java:5575)
at
android.support.design.widget.HeaderScrollingViewBehavior.layoutChild(HeaderScrollingViewBehavior.java:131)
at
android.support.design.widget.ViewOffsetBehavior.onLayoutChild(ViewOffsetBehavior.java:42)
at
android.support.design.widget.AppBarLayout$ScrollingViewBehavior.onLayoutChild(AppBarLayout.java:1391)
at
android.support.design.widget.CoordinatorLayout.onLayout(CoordinatorLayout.java:870)
at android.view.View.layout(View.java:17637)
at android.view.ViewGroup.layout(ViewGroup.java:5575)
at android.widget.FrameLayout.layoutChildren(FrameLayout.java:323)
at android.widget.FrameLayout.onLayout(FrameLayout.java:261)
at android.view.View.layout(View.java:17637)
at android.view.ViewGroup.layout(ViewGroup.java:5575)
at android.widget.LinearLayout.setChildFrame(LinearLayout.java:1741)
at android.widget.LinearLayout.layoutVertical(LinearLayout.java:1585)
at android.widget.LinearLayout.onLayout(LinearLayout.java:1494)
at android.view.View.layout(View.java:17637)
at android.view.ViewGroup.layout(ViewGroup.java:5575)
at android.widget.FrameLayout.layoutChildren(FrameLayout.java:323)
at android.widget.FrameLayout.onLayout(FrameLayout.java:261)
at android.view.View.layout(View.java:17637)
at android.view.ViewGroup.layout(ViewGroup.java:5575)
at android.widget.LinearLayout.setChildFrame(LinearLayout.java:1741)
at android.widget.LinearLayout.layoutVertical(LinearLayout.java:1585)
at android.widget.LinearLayout.onLayout(LinearLayout.java:1494)
at android.view.View.layout(View.java:17637)
at android.view.ViewGroup.layout(ViewGroup.java:5575)
at android.widget.FrameLayout.layoutChildren(FrameLayout.java:323)
at android.widget.FrameLayout.onLayout(FrameLayout.java:261)
at com.android.internal.policy.DecorView.onLayout(DecorView.java:726)
at android.view.View.layout(View.java:17637)
at android.view.ViewGroup.layout(ViewGroup.java:5575)
at android.view.ViewRootImpl.performLayout(ViewRootImpl.java:2346)
at android.view.ViewRootImpl.performTraversals(ViewRootImpl.java:2068)
06-22 10:11:41.107 22646-22646/com.example.aymen.schoolmanager
E/AndroidRuntime: at
android.view.ViewRootImpl.doTraversal(ViewRootImpl.java:1254)
at
android.view.ViewRootImpl$TraversalRunnable.run(ViewRootImpl.java:6337)
at
android.view.Choreographer$CallbackRecord.run(Choreographer.java:874)
at android.view.Choreographer.doCallbacks(Choreographer.java:686)
at android.view.Choreographer.doFrame(Choreographer.java:621)
at
android.view.Choreographer$FrameDisplayEventReceiver.run(Choreographer.java:860)
at android.os.Handler.handleCallback(Handler.java:751)
at android.os.Handler.dispatchMessage(Handler.java:95)
at android.os.Looper.loop(Looper.java:154)
at android.app.ActivityThread.main(ActivityThread.java:6119)
at java.lang.reflect.Method.invoke(Native Method)
at
com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:886)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:776)
line 68 points to:
holder.textViewHead.setText(idd.get(position).getSubject());
line 20 points to:
class Adapter extends RecyclerView.Adapter<Adapter.ViewHolder>
Here's my code:
My database class handler:
public class DBhandler extends SQLiteOpenHelper {
private static final String databas_name="newdata.db";
public static final int databas_version=1;
public static String ID="id";
int id;
SQLiteDatabase dj;
ArrayList<dates> er=new ArrayList<dates>();
SQLiteDatabase db;
DBhandler helper;
String TYPE="type";
String sub="Subject";
String Title="Title";
String det="Detail";
String TabN="ClassExams";
int i;
public DBhandler(Context context)
{
super(context,databas_name,null,databas_version);
}
@Override
public void onCreate(SQLiteDatabase db) {
db.execSQL("CREATE TABLE if not EXISTS ClassExams(id INTEGER primary key,type TEXT,Subject TEXT,Title TEXT,Detail TEXT) ");
}
@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
db.execSQL("DROP table if EXISTS ClassExams");
onCreate(db);
}
public void insert(String type, String sub, String title, String detaill)
{
SQLiteDatabase db=this.getWritableDatabase();
ContentValues contentValues=new ContentValues();
contentValues.put("type",type);
contentValues.put("Subject",sub);
contentValues.put("Title",title);
contentValues.put("Detail",detaill);
db.insert("ClassExams",null,contentValues);
db.close();
}
public ArrayList getAs(String Type)
{
String DATABASE_TABLE="ClassExams";
String type="type";
String quer = "SELECT * FROM " + DATABASE_TABLE + " WHERE " + type + "='" + Type+"'";
ArrayList arrayList=new ArrayList();
SQLiteDatabase db=this.getReadableDatabase();
Cursor res=db.rawQuery(quer,null);
res.moveToFirst();
while (res.isAfterLast()==false){
arrayList.add(res.getString(res.getColumnIndex("id")));
// arrayList.add(res.getString(res.getColumnIndex("Subject")));
// arrayList.add(res.getString(res.getColumnIndex("Title")));
// arrayList.add(res.getString(res.getColumnIndex("Detail")));
res.moveToNext();
}
return arrayList;
}
public void deleteNote(int x){
String TABLE_NAME="ClassExams";
String ID="id";
SQLiteDatabase db = this.getWritableDatabase();
db.delete(TABLE_NAME, ID + " = ?",new String[] {String.valueOf(x)});
}
}
My adapter class:
public class Adapter extends RecyclerView.Adapter<Adapter.ViewHolder> {
Context activity;
private ArrayList<dates> idd;
public class ViewHolder extends RecyclerView.ViewHolder {
public TextView textViewHead;
public TextView textViewDown;
public TextView buttonViewOption;
public int position;
public ViewHolder(View itemView) {
super(itemView);
textViewHead = (TextView) itemView.findViewById(id.text1);
textViewDown = (TextView) itemView.findViewById(id.text2);
buttonViewOption = (TextView) itemView.findViewById(R.id.textViewOptions);
}
}
public Adapter (Context context, ArrayList<dates> id) {
this.activity=context;
this.idd=id;
}
@Override
public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
LayoutInflater inflater=LayoutInflater.from(activity);
// View row=inflater.inflate(layout.costum_row,parent,false);
View view = LayoutInflater.from(parent.getContext()).inflate(layout.costum_row, null);
ViewHolder holder=new ViewHolder(view);
return holder;
}
public void onBindViewHolder(final Adapter.ViewHolder holder, final int position) {
// dates object=idd.get(position);
// String firstText = object.getDetail();
// String secondText = object.getSubject();
holder.textViewDown.setText("Somthing");
holder.textViewHead.setText(idd.get(position).getSubject());
holder.buttonViewOption.setOnClickListener(new View.OnClickListener() {
public void onClick(View view) {
PopupMenu popup = new PopupMenu(activity, holder.buttonViewOption);
popup.inflate(R.menu.option_menu);
popup.setOnMenuItemClickListener(new PopupMenu.OnMenuItemClickListener() {
@Override
public boolean onMenuItemClick(MenuItem item) {
switch (item.getItemId()) {
case id.Update:
break;
case R.id.menu2:
break;
case id.Delete:
delete();
//db.deleteNote(Integer.parseInt(j));
// db.deleteNote(getid);
}
return false;
}
});
//displaying the popup
popup.show();
}
public void delete() {
idd.remove(position);
notifyItemRemoved(position);
notifyItemRangeChanged(position, idd.size());
holder.itemView.setVisibility(View.GONE);
}
});
}
@Override
public int getItemCount() {
return idd.size();}}
My class:
public class dates {
String Subject,Title,Detail,type;
int id;
public dates(String subject, String title, String detail, String type, int id) {
this.Subject = subject;
this.Title = title;
this.Detail = detail;
this.type = type;
this.id = id;
}
dates()
{
}
public String getSubject() {
return Subject;
}
public void setSubject(String subject) {
Subject= subject;
}
public String getTitle() {
return Title;
}
public void setTitle(String title) {
Title = title;
}
public String getDetail() {
return Detail;
}
public void setDetail(String detail) {
Detail = detail;
}
public String getType() {
return type;
}
public void setType(String type) {
this.type = type;
}
public int getId() {
return id;
}
public void seti(int id) {
this.id = id;
}
A:
Not all the necessary code is shown here, but I assume the Array list coming from ArrayList DBHandler.getAs() is passed as id parameter to the Adapter constuctor
public Adapter (Context context, ArrayList<dates> id)
There should have been a compiler warning about "unchecked or unsafe operations".
What getAs returns is actually a list containing String objects and this is now interpreted as a list containing dates objects, which results in the class cast exception as soon as one of the elements is accessed.
Two lessons can be learned from this:
Don't ignore compiler warnings
Don't use raw collection classes
|
[
"workplace.meta.stackexchange",
"0000000008.txt"
] | Q:
How should we handle cultural issues?
Just glancing over a few questions, I see many that are culture specific, eg:
What are some guidelines for appropriate social drinking at work? - this will vary greatly between secular and Muslim cultures (also note, this is a list question)
Switching jobs - how soon is too soon?
How to select interview attire for a technical job interview?
How should we handle issues that are affected by culture, whether that is per country (includes culture and religion), per role (eg different for an accountant or a programmer) or per branch (eg military to the arts)?
E.g. Is multiple questions with tags the way to go?
A:
On Judaism.SE, we have the same sort of issue due to different sub-cultures within Judaism maintaining traditions including different practices and beliefs and due to different rabbinic authorities giving different rulings on various issues. The community tends to deal with this in one of two ways.
One is that some questions specify that they're asking about rulings within a particular line of tradition or even according to a specific rabbi. Valid answers to such questions would be within the specified parameters.
The other, which is actually employed more frequently, is that many questions get multiple equally-valid answers that refer to different traditions or cite authorities who disagree. I actually see this possibility as a strength of the SE model, which allows for multiple answers, taking advantage of the various sets of knowledge and experience that exist in the community.
I think that the same approach should work here. If askers want to specify (within the question body and also possibly by tagging) the culture they're asking within, fine. If not, and answerers are aware that the right answer may differ depending on the cultural context, they should consider noting as much in their answers, and specifying what cultural context [s] their answers address.
A:
I don't think tagging should be used to differentiate these questions. They could be easily missed. For instance, if we had 7 questions all titled:
What are some guidelines for appropriate social drinking at work?
and all 7 of those questions had different tags, it might not be clear to everyone that the scope of the question is somehow tied to the tag.
Tags should be used to categorize questions, but they should not be required for a reader to understand what the question is about. Instead, the question should contain enough detail to stand on it's own without the tags.
On StackOverflow, when I answer a JavaScript question, I can tell the question is about JavaScript simply by reading the question. The questions stand on their own without tags; I don't need the tag in order to tell me it's a JavaScript question. However, when searching for JavaScript questions, the tags are very helpful.
Thus, we should target questions like:
I work in the United States, what are some guidelines for appropriate social drinking at work?
I live in Afghanistan, what are some guidelines for appropriate social drinking at work?
Additionally, these details don't necessarily need to go in the question title. They should also be included in the question body.
|
[
"stackoverflow",
"0024432247.txt"
] | Q:
How to split string by new lines in JAVA?
I want to split string by new lines in Java.I am using following regex -
str.split("\\r|\\n|\\r\\n");
But still it is not splitting string by new lines.
Input -
0
0
0
0
Output = String [] array = {"0000"} instead I want = String [] array = {"0","0","0","0"}.
I have read various solutions on stack overflow but nothing works for me.
Code is -
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.text.DecimalFormat;
public class Input {
public static void main(String[] args) {
BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
String line;
String text = "";
try {
while((line=br.readLine())!=null){
text = text + line;
}
} catch (IOException e) {
e.printStackTrace();
}
String [] textarray = text.trim().split("[\\r\\n]+");
for(int j=0;j<textarray.length;j++)
System.out.println(textarray[j]);
// System.out.print("");
// for(int i=((textarray.length)-1);i>=0;i--){
// long k = Long.valueOf(textarray[i]).longValue();
// System.out.println(k);
//// double sqrt = Math.sqrt(k);
//// double value = Double.parseDouble(new DecimalFormat("##.####").format(sqrt));
//// System.out.println(value);
////
//// }
}
A:
When you call br.readLine(), the newline characters are stripped from the end of the string. So if you type 0 + ENTER four times, you are trying to split the string "0000".
You would be better to read items in from stdin and store them in an expandable data structure, such as a List<String>. No need to split things if you've already read them separately.
|
[
"stackoverflow",
"0061340123.txt"
] | Q:
How the expression !A + (A . !B) = !(A.B)?
I have an expression !A+(A.!B) and on an expression solver, it gives the !A+(A.!B) = !(A.B)?.
The solver notified that "Apply the Absorption Law" A.B+!A = B+!A.
I have made the truth tables for both the expressions and the answer was correct. But the problem is I can not understand how the absorption law has got implemented to my expression !A+(A.!B)?
Can someone please explain in details how the absorption law has got implemented to my expression?
A:
I am going to assume that + = OR, . = AND and ! = NOT.
The absorption law was applied in the very first step:
!A + A.!B
= !A + !B (if the first monomial does not hold, A is "true"
and thus does not need to be checked again)
= !(A.B) (De Morgan's rule)
|
[
"stackoverflow",
"0011316906.txt"
] | Q:
Jquery toggle background color
I have a jquery function that when a li is clicked, the li expands. That part is working fine. Now, I want, when the li is clicked it toggles a background color. But it works, however when i have to click on the li item again to untoggle the background color. Can someone assist me in the right direction on how to achieve this.
$(function() {
$('.a').click(function() {
var name = $(this).attr("name");
var content = $('.content[name=' + name + ']');
$('.content').not(content).hide('fast');
$('.selected').css('background', 'yellow');
content.slideToggle('fast');
});
$("li").click(function() {
$(this).toggleClass("highlight");
});
});
A:
On every click set your <li>-s to default color and highlight the current:
$("li").click(function() {
$("li").removeClass("highlight");
$(this).addClass("highlight");
});
...
UPDATE
http://jsfiddle.net/NXVhE/4/
$(function() {
$('.a').click(function() {
$(this).removeClass("highlight");
var name = $(this).attr("name");
var content = $('.content[name=' + name + ']');
$('.content').not(content).hide();
content.toggle();
});
$("a").click(function () {
$("a").removeClass("highlight");
if ( $(".content").is(":visible") ) {
$(this).addClass("highlight");
}
});
});
|
[
"stackoverflow",
"0013090211.txt"
] | Q:
NSInternalInconsistencyException(Invalid update: invalid number of rows in section 0)
I design the process is that:
Enter into a CourseAddViewController(UITableViewController) via a Model Segue;
The right bar button display "Done"(At this status, the tableview display all data in eachrow with "-", but the additional row at the bottom with "+");
Press "Done" button, the save the data.
When I add the statement "self.editing = YES;" in - (void)viewDidLoad method, it will crash.
I found that it didn't perform "tableView:cellForRowAtIndexPath:" method.But, actually I trust that there is 1 row in section 0 via the result of NSLog().
If I don't add "self.editing = YES;", it run correctly.
- (void)viewDidLoad
{
[super viewDidLoad];
self.navigationItem.rightBarButtonItem = self.editButtonItem;
self.editing = YES; // here: adding it cause crash
}
After performing "insertRowsAtIndexPaths:withRowAnimation:", it crashed.
Two statement:
[self.tableView beginUpdates];
[self.tableView endUpdates];
add them or not, all cuase crash.
- (void)setEditing:(BOOL)editing animated:(BOOL)animated
{
[super setEditing:editing animated:animated];
[self.tableView beginUpdates];
NSInteger booksCount = self.course.books.count;
NSArray *booksInsertIndexPath = [NSArray arrayWithObject:[NSIndexPath indexPathForRow:booksCount inSection:0]];
if (editing) {
[self.tableView insertRowsAtIndexPaths:booksInsertIndexPath
withRowAnimation:UITableViewRowAnimationBottom]; // then, it crashes
} else {
[self.tableView deleteRowsAtIndexPaths:booksInsertIndexPath
withRowAnimation:UITableViewRowAnimationBottom];
}
[self.tableView endUpdates];
// ...
}
Other method,
- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView
{
NSLog(@"%d", self.fetchedResultsController.sections.count); // the result is always 1;
return self.fetchedResultsController.sections.count;
}
Other method,
- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
{
id <NSFetchedResultsSectionInfo> sectionInfo = [self.fetchedResultsController.sections objectAtIndex:section];
NSInteger rows = [sectionInfo numberOfObjects];
if (self.editing)
rows++;
NSLog(@"%d", rows); // the result is always 1;
return rows;
}
Other method,
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
static NSString *CellIdentifier = @"Cell";
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
if (!cell)
cell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:CellIdentifier];
id <NSFetchedResultsSectionInfo> sectionInfo = [self.fetchedResultsController.sections objectAtIndex:indexPath.section];
NSInteger rows = [sectionInfo numberOfObjects];
if (self.editing && rows == indexPath.row) {
return cell;
}
[self configureCell:cell atIndexPath:indexPath];
// NSLog(@"%d-%d-%d-%d", self.editing, rows, indexPath.section, indexPath.row);
return cell;
}
New Edit:
2012-10-27 08:44:29.934 Course Table[306:fb03] *** Assertion failure in
-[UITableView _endCellAnimationsWithContext:], /SourceCache/UIKit_Sim/
UIKit-914.84/UITableView.m:1037
2012-10-27 08:44:29.935 Course Table[306:fb03] CRASH: Invalid update:
invalid number of rows in section 0. The number of rows contained in
an existing section after the update (1) must be equal to the number
of rows contained in that section before the update (1), plus or
minus the number of rows inserted or deleted from that section
(1 inserted, 0 deleted) and plus or minus the number of rows moved
into or out of that section (0 moved in, 0 moved out).
2012-10-27 08:44:29.942 Course Table[306:fb03] Stack Trace: (
0 CoreFoundation 0x016cf03e __exceptionPreprocess + 206
1 libobjc.A.dylib 0x01860cd6 objc_exception_throw + 44
2 CoreFoundation 0x01677a48 +[NSException raise:format:arguments:] + 136
3 Foundation 0x009d12cb -[NSAssertionHandler handleFailureInMethod:object:file:lineNumber:description:] + 116
4 UIKit 0x000bf3d7 -[UITableView(_UITableViewPrivate) _endCellAnimationsWithContext:] + 12439
5 UIKit 0x000ca6d2 -[UITableView _updateRowsAtIndexPaths:updateAction:withRowAnimation:] + 295
6 UIKit 0x000ca711 -[UITableView insertRowsAtIndexPaths:withRowAnimation:] + 55
7 Course Table 0x0000ef42 -[CTXCourseAddViewController setEditing:animated:] + 434
8 UIKit 0x0010de4c -[UIViewController(UINavigationControllerItem) setEditing:] + 49
9 Course Table 0x0000ec1f -[CTXCourseAddViewController viewDidLoad] + 655
10 UIKit 0x00101a1e -[UIViewController view] + 184
11 UIKit 0x00100fec -[UIViewController nextResponder] + 34
12 UIKit 0x00127f1d -[UIResponder _containsResponder:] + 40
13 UIKit 0x001121cb -[UINavigationController defaultFirstResponder] + 83
14 UIKit 0x00128df1 -[UIResponder(Internal) _deepestDefaultFirstResponder] + 36
15 UIKit 0x00128ea9 -[UIResponder(Internal) _promoteDeepestDefaultFirstResponder] + 36
16 UIKit 0x00322508 -[UIWindowController transitionViewDidStart:] + 89
17 UIKit 0x000df401 -[UITransitionView _didStartTransition] + 93
18 UIKit 0x000e008b -[UITransitionView transition:fromView:toView:] + 1169
19 UIKit 0x00321d6c -[UIWindowController transition:fromViewController:toViewController:target:didEndSelector:] + 6114
20 UIKit 0x00108857 -[UIViewController presentViewController:withTransition:completion:] + 3579
21 UIKit 0x001089bc -[UIViewController presentViewController:animated:completion:] + 112
22 UIKit 0x001089fc -[UIViewController presentModalViewController:animated:] + 56
23 UIKit 0x00470f4a -[UIStoryboardModalSegue perform] + 250
24 UIKit 0x004654d0 -[UIStoryboardSegueTemplate perform:] + 174
25 CoreFoundation 0x016d0e99 -[NSObject performSelector:withObject:withObject:] + 73
26 UIKit 0x0003d14e -[UIApplication sendAction:to:from:forEvent:] + 96
27 UIKit 0x0027ba0e -[UIBarButtonItem(UIInternal) _sendAction:withEvent:] + 145
28 CoreFoundation 0x016d0e99 -[NSObject performSelector:withObject:withObject:] + 73
29 UIKit 0x0003d14e -[UIApplication sendAction:to:from:forEvent:] + 96
30 UIKit 0x0003d0e6 -[UIApplication sendAction:toTarget:fromSender:forEvent:] + 61
31 UIKit 0x000e3ade -[UIControl sendAction:to:forEvent:] + 66
32 UIKit 0x000e3fa7 -[UIControl(Internal) _sendActionsForEvents:withEvent:] + 503
33 UIKit 0x000e3266 -[UIControl touchesEnded:withEvent:] + 549
34 UIKit 0x000623c0 -[UIWindow _sendTouchesForEvent:] + 513
35 UIKit 0x000625e6 -[UIWindow sendEvent:] + 273
36 UIKit 0x00048dc4 -[UIApplication sendEvent:] + 464
37 UIKit 0x0003c634 _UIApplicationHandleEvent + 8196
38 GraphicsServices 0x015b9ef5 PurpleEventCallback + 1274
39 CoreFoundation 0x016a3195 __CFRUNLOOP_IS_CALLING_OUT_TO_A_SOURCE1_PERFORM_FUNCTION__ + 53
40 CoreFoundation 0x01607ff2 __CFRunLoopDoSource1 + 146
41 CoreFoundation 0x016068da __CFRunLoopRun + 2218
42 CoreFoundation 0x01605d84 CFRunLoopRunSpecific + 212
43 CoreFoundation 0x01605c9b CFRunLoopRunInMode + 123
44 GraphicsServices 0x015b87d8 GSEventRunModal + 190
45 GraphicsServices 0x015b888a GSEventRun + 103
46 UIKit 0x0003a626 UIApplicationMain + 1163
47 Course Table 0x000020dd main + 141
48 Course Table 0x00002045 start + 53
)
2012-10-27 08:44:29.945 Course Table[306:fb03] *** Terminating app due to
uncaught exception 'NSInternalInconsistencyException', reason: 'Invalid
update: invalid number of rows in section 0. The number of rows contained
in an existing section after the update (1) must be equal to the number
of rows contained in that section before the update (1), plus or minus
the number of rows inserted or deleted from that section (1 inserted,
0 deleted) and plus or minus the number of rows moved into or out of that
section (0 moved in, 0 moved out).
terminate called throwing an exception(lldb)
A:
Just add
[self.tableView reloadData];
before
self.editing = YES;
This is needed because the table view doesn't initially have information about its data source and delegate; if you create a table view, it always needs to be sent a reloadData message as part of its initialization.
|
[
"stackoverflow",
"0038851380.txt"
] | Q:
Our ASP.NET core RC1 application stopped working and then started working again
We have built an .NET application on ASP.NET core RC1 (release candidate 1) and deployed it on Windows Azure in an Web App container. By August the 2'nd the application stopped working over night. We found out it was caused by the fact that Microsoft stopped supporting RC1 (and RC2 for that matter) by that date.
The strange thing is that by today the application started working again without any change from our side.
Can anyone explain that behavior? I don't feel very comfortable with these kind of changes in the container environments.
NB: I should add that the error we saw in the log files was this one:
MissingMethodException: Method not found: 'Newtonsoft.Json.JsonSerializerSettings Microsoft.AspNet.Mvc.MvcJsonOptions.get_SerializerSettings()'
A:
I can explain what happened: a version of Json.NET v6.0.4 was mistakenly added to the GAC. Due to the way Json.NET is versioned, apps that had a different 6.x version in their bin folder ended up loading the one in the GAC. Your RC1 app probably has v6.0.7, and broke because v6.0.4 was missing APIs.
This assembly is not supposed to be in the GAC at all, so when we realized the issue, we removed it, which is when your app started working again. Apologies for the downtime.
That being said, you really should move away from RC1, which is not officially supported.
|
[
"stackoverflow",
"0033003789.txt"
] | Q:
AngularJs memory
I have an Angular application that loads in only the needed controller / factory or service when it needs to. However i started wondering if all of these scripts eats up the memory the longer my client uses my application.
Take for instance the following example:
Client1 logs into my application here the following controllers are loaded:
LoginController
UserController
Together with these some factories and services are loaded in to store the user for furture reference.
As my Client1 goes through my system the application keeps on adding scripts but never dumping the ones it does not use.
At the last page of my application all of my controllers,factories and services has been loaded and stored in the memory however only a few is actually being used and only a few will be used again.
Should i be concerned about this once my application grows or is that just the normal procedure of AngularJs?
A:
It sounds to me like this will be the least of your concerns if your application grows. When it comes to overhead and optimization, there's a lot of issues that will be significantly more memory consuming than loaded javascript files.
For instance, too many bindings in your view, listeners you haven't removed on a $scope $destroy event, caching of API calls. I think you shouldn't really worry about this, your application would have to be way too big for this to be an issue, and when this happens, you'll be able to simply optimize the many other areas that are more worrying.
Here you have a few tips to optimize your angular app before you even take this into account.
|
[
"stackoverflow",
"0007674688.txt"
] | Q:
Mac Spotlight-API: how to search email's "to", "from" or "subject" fields
At the moment I have spotlight-api code which searches email's body. I'm using NSMetadataQuery and creating predicate for "kMDItemTextContent like[c] %@". This works fine when requested "search-term" is in body of email.
In Spotlight App (magnifier icon in top right) if I enter "to: john" I'll get list of emails in which "to" field contains word "john" (e.g. part of some email address [email protected]).
I tried to achieve this with [NSCompoundPredicate orPredicateWithSubpredicates:] by adding additional predicates of type "kMDItemRecipients", "kMDItemRecipientEmailAddresses", "kMDItemAuthors", "kMDItemAuthorEmailAddresses" and "kMDItemSubject".
Unfortunately this doesn't return desired emails.
Does anyone know how to achieve this by using Spotlight-API?
Below is my code for this:
NSString *predicateFormat = @"kMDItemTextContent like[c] %@";
NSPredicate *predicateToRun = [NSPredicate predicateWithFormat:predicateFormat, self.searchKey];
NSString *predicateFormat1 = @"kMDItemTitle like[c] %@";
NSPredicate *predicateToRun1 = [NSPredicate predicateWithFormat:predicateFormat1, self.searchKey];
NSString *predicateFormat2 = @"kMDItemAuthorEmailAddresses like[c] %@";
NSPredicate *predicateToRun2 = [NSPredicate predicateWithFormat:predicateFormat2, self.searchKey];
NSString *predicateFormat3 = @"kMDItemAuthors like[c] %@";
NSPredicate *predicateToRun3 = [NSPredicate predicateWithFormat:predicateFormat3, self.searchKey];
NSString *predicateFormat4 = @"kMDItemRecipientEmailAddresses like[c] %@";
NSPredicate *predicateToRun4 = [NSPredicate predicateWithFormat:predicateFormat4, self.searchKey];
NSString *predicateFormat5 = @"kMDItemRecipients like[c] %@";
NSPredicate *predicateToRun5 = [NSPredicate predicateWithFormat:predicateFormat5, self.searchKey];
NSString *predicateFormat6 = @"kMDItemSubject like[c] %@";
NSPredicate *predicateToRun6 = [NSPredicate predicateWithFormat:predicateFormat6, self.searchKey];
NSUInteger options = (NSCaseInsensitivePredicateOption|NSDiacriticInsensitivePredicateOption);
NSPredicate *compPred = [NSComparisonPredicate
predicateWithLeftExpression:[NSExpression expressionForKeyPath:@"*"]
rightExpression:[NSExpression expressionForConstantValue:self.searchKey]
modifier:NSDirectPredicateModifier
type:NSLikePredicateOperatorType
options:options];
predicateToRun = [NSCompoundPredicate orPredicateWithSubpredicates:
[NSArray arrayWithObjects:
compPred,
predicateToRun, predicateToRun1, predicateToRun2, predicateToRun3, predicateToRun4,
predicateToRun5, predicateToRun6, nil]];
predicateToRun = [NSCompoundPredicate andPredicateWithSubpredicates:
[NSArray arrayWithObjects:predicateToRun, [NSPredicate predicateWithFormat:@"(kMDItemContentType != 'public.vcard')"], nil]];
[self.query setPredicate:predicateToRun];
[self.query startQuery];
A:
I know how to do this with MDQuery - which in my opinion is simpler.
You can use basically the same queries as you can use in mdfind from the command line.
make a search string like: (NOT tested)
((((kMDItemAuthorEmailAddresses == "*john*"cd)) || ((kMDItemAuthors == "*john*"cd))) && (kMDItemContentType == 'com.apple.mail.emlx'))
also in terminal
mdls /path/to/library/mail/v2/24324.emlx
will show what to search on for emails. Its your friend
Note how you can hook up objective c notifications.
NSString* query = some string ;
MDQueryRef mdQuery = MDQueryCreate(nil, (CFStringRef)query, nil, nil);
// if something is goofy, we won't get the query back, and all calls involving a mil MDQuery crash. So return:
if (mdQuery == nil)
return;
NSNotificationCenter* nf = [NSNotificationCenter defaultCenter];
[nf addObserver:self selector:@selector(progressUpradeQuery:) name:(NSString*)kMDQueryProgressNotification object:(id) mdQuery];
[nf addObserver:self selector:@selector(finishedUpradeQuery:) name:(NSString*)kMDQueryDidFinishNotification object:(id) mdQuery];
[nf addObserver:self selector:@selector(updatedUpradeQuery:) name:(NSString*)kMDQueryDidUpdateNotification object:(id) mdQuery];
// Should I run this query on the network too? Difficult decision, as I think that this will slow stuff way down.
// But i think it will only query leopard servers so perhaps ok
//MDQuerySetSearchScope(mdQuery, (CFArrayRef)[NSArray arrayWithObjects:(NSString*)kMDQueryScopeComputer, (NSString*)kMDQueryScopeNetwork, nil], 0);
// start it
BOOL queryRunning = MDQueryExecute(mdQuery, kMDQueryWantsUpdates);
if (!queryRunning)
{
CFRelease(mdQuery);
mdQuery = nil;
// leave this log message in...
NSLog(@"MDQuery failed to start.");
return;
}
Tom
|
[
"stackoverflow",
"0063212830.txt"
] | Q:
Set submenu position from top
I am a backend developer and don't know much about the designing. In my ecommerce project, I am trying to get sub-menus to be displayed from the top no matter where the parent menu position.
In my menu HTML I have:
<ul id="nav">
<li class="site-name"><a href="#">Social </a></li>
<li class="yahoo"><a href="#">Yahoo</a>
<ul style="">
<li><a href="#">Yahoo Games »</a>
<ul style="">
<li><a href="#">Board Games</a></li>
<li><a href="#">Card Games</a></li>
<li><a href="#">Puzzle Games</a></li>
<li><a href="#">Skill Games »</a>
<ul style="">
<li><a href="#">Yahoo Pool</a></li>
<li><a href="#">Chess</a></li>
</ul>
</li>
</ul>
</li>
<li><a href="#">Yahoo Search</a></li>
<li><a href="#">Yahoo Answsers</a></li>
</ul>
</li>
<li class="google"><a href="#">Google</a>
<ul style="">
<li><a href="#">Google mail</a></li>
<li><a href="#">Google Plus</a></li>
<li><a href="#">Google Search »</a>
<ul>
<li><a href="#">Search Images</a></li>
<li><a href="#">Search Web</a></li>
</ul>
</li>
</ul>
</li>
<li class="twitter"><a href="#">Twitter</a>
<ul style="">
<li><a href="#">New Tweets</a></li>
<li><a href="#">Compose a Tweet</a></li>
</ul>
</li>
</ul>
And the CSS is to this menu is:
#nav{
height: 39px;
font: 12px Geneva, Arial, Helvetica, sans-serif;
background: #3AB3A9;
border: 1px solid #30A097;
border-radius: 3px;
min-width:500px;
margin-left: 0px;
padding-left: 0px;
}
#nav li{
list-style: none;
display: block;
float: left;
height: 40px;
position: relative;
border-right: 1px solid #52BDB5;
}
#nav li a{
padding: 0px 10px 0px 30px;
margin: 0px 0;
line-height: 40px;
text-decoration: none;
border-right: 1px solid #389E96;
height: 40px;
color: #FFF;
text-shadow: 1px 1px 1px #66696B;
}
#nav ul{
background: #f2f5f6;
padding: 0px;
border-bottom: 1px solid #DDDDDD;
border-right: 1px solid #DDDDDD;
border-left:1px solid #DDDDDD;
border-radius: 0px 0px 3px 3px;
box-shadow: 2px 2px 3px #ECECEC;
-webkit-box-shadow: 2px 2px 3px #ECECEC;
-moz-box-shadow:2px 2px 3px #ECECEC;
width:170px;
}
#nav .site-name,#nav .site-name:hover{
padding-left: 10px;
padding-right: 10px;
color: #FFF;
text-shadow: 1px 1px 1px #66696B;
font: italic 20px/38px Georgia, "Times New Roman", Times, serif;
background: url(images/saaraan.png) no-repeat 10px 5px;
width: 160px;
border-right: 1px solid #52BDB5;
}
#nav .site-name a{
width: 129px;
overflow:hidden;
}
#nav li.facebook{
background: url(../images/facebook.png) no-repeat 9px 12px;
}
#nav li.facebook:hover {
background: url(../images/facebook.png) no-repeat 9px 12px #3BA39B;
}
#nav li.yahoo{
background: url(../images/yahoo.png) no-repeat 9px 12px;
}
#nav li.yahoo:hover {
background: url(../images/yahoo.png) no-repeat 9px 12px #3BA39B;
}
#nav li.google{
background: url(../images/google.png) no-repeat 9px 12px;
}
#nav li.google:hover {
background: url(../images/google.png) no-repeat 9px 12px #3BA39B;
}
#nav li.twitter{
background: url(../images/twitter.png) no-repeat 9px 12px;
}
#nav li.twitter:hover {
background: url(../images/twitter.png) no-repeat 9px 12px #3BA39B;
}
#nav li:hover{
background: #3BA39B;
}
#nav li a{
display: block;
}
#nav ul li {
border-right:none;
border-bottom:1px solid #DDDDDD;
width:170px;
height:39px;
}
#nav ul li a {
border-right: none;
color:#6791AD;
text-shadow: 1px 1px 1px #FFF;
border-bottom:1px solid #FFFFFF;
}
#nav ul li:hover{background:#DFEEF0;}
#nav ul li:last-child { border-bottom: none;}
#nav ul li:last-child a{ border-bottom: none;}
/* Sub menus */
#nav ul{
display: none;
visibility:hidden;
position: absolute;
top: 40px;
}
/* Third-level menus */
#nav ul ul{
top: 0px;
left:170px;
display: none;
visibility:hidden;
border: 1px solid #DDDDDD;
}
/* Fourth-level menus */
#nav ul ul ul{
top: 0px;
left:170px;
display: none;
visibility:hidden;
border: 1px solid #DDDDDD;
}
#nav ul li{
display: block;
visibility:visible;
}
#nav li:hover > ul{
display: block;
visibility:visible;
}
When executes on the server it displayed like this:
https://jsfiddle.net/uqfsvn4L/
As you can see the submenu of Google Search displays from the top of its parent position but I want it to be displayed from the top of the main menu. How can I get the submenu display from the top?
My expected output would be:
A:
Remove position: relative from #nav li and then adjust the top property of #nav ul. Here is the working example
#nav {
height: 39px;
font: 12px Geneva, Arial, Helvetica, sans-serif;
background: #3AB3A9;
border: 1px solid #30A097;
border-radius: 3px;
min-width: 500px;
margin-left: 0px;
padding-left: 0px;
}
#nav li {
list-style: none;
display: block;
float: left;
height: 40px;
border-right: 1px solid #52BDB5;
}
#nav li a {
padding: 0px 10px 0px 30px;
margin: 0px 0;
line-height: 40px;
text-decoration: none;
border-right: 1px solid #389E96;
height: 40px;
color: #FFF;
text-shadow: 1px 1px 1px #66696B;
}
#nav ul {
background: #f2f5f6;
padding: 0px;
border-bottom: 1px solid #DDDDDD;
border-right: 1px solid #DDDDDD;
border-left: 1px solid #DDDDDD;
border-radius: 0px 0px 3px 3px;
box-shadow: 2px 2px 3px #ECECEC;
-webkit-box-shadow: 2px 2px 3px #ECECEC;
-moz-box-shadow: 2px 2px 3px #ECECEC;
width: 170px;
}
#nav .site-name,
#nav .site-name:hover {
padding-left: 10px;
padding-right: 10px;
color: #FFF;
text-shadow: 1px 1px 1px #66696B;
font: italic 20px/38px Georgia, "Times New Roman", Times, serif;
background: url(images/saaraan.png) no-repeat 10px 5px;
width: 160px;
border-right: 1px solid #52BDB5;
}
#nav .site-name a {
width: 129px;
overflow: hidden;
}
#nav li.facebook {
background: url(../images/facebook.png) no-repeat 9px 12px;
}
#nav li.facebook:hover {
background: url(../images/facebook.png) no-repeat 9px 12px #3BA39B;
}
#nav li.yahoo {
background: url(../images/yahoo.png) no-repeat 9px 12px;
}
#nav li.yahoo:hover {
background: url(../images/yahoo.png) no-repeat 9px 12px #3BA39B;
}
#nav li.google {
background: url(../images/google.png) no-repeat 9px 12px;
}
#nav li.google:hover {
background: url(../images/google.png) no-repeat 9px 12px #3BA39B;
}
#nav li.twitter {
background: url(../images/twitter.png) no-repeat 9px 12px;
}
#nav li.twitter:hover {
background: url(../images/twitter.png) no-repeat 9px 12px #3BA39B;
}
#nav li:hover {
background: #3BA39B;
}
#nav li a {
display: block;
}
#nav ul li {
border-right: none;
border-bottom: 1px solid #DDDDDD;
width: 170px;
height: 39px;
}
#nav ul li a {
border-right: none;
color: #6791AD;
text-shadow: 1px 1px 1px #FFF;
border-bottom: 1px solid #FFFFFF;
}
#nav ul li:hover {
background: #DFEEF0;
}
#nav ul li:last-child {
border-bottom: none;
}
#nav ul li:last-child a {
border-bottom: none;
}
/* Sub menus */
#nav ul {
display: none;
visibility: hidden;
position: absolute;
top:48x;
}
/* Third-level menus */
#nav ul ul {
top: 0px;
left: 170px;
display: none;
visibility: hidden;
border: 1px solid #DDDDDD;
min-height: 100%
}
/* Fourth-level menus */
#nav ul ul ul {
top: 0px;
left: 170px;
display: none;
visibility: hidden;
border: 1px solid #DDDDDD;
min-height: 100%
}
#nav ul li {
display: block;
visibility: visible;
}
#nav li:hover>ul {
display: block;
visibility: visible;
}
<ul id="nav">
<li class="site-name"><a href="#">Social </a></li>
<li class="yahoo"><a href="#">Yahoo</a>
<ul>
<li><a href="#">Yahoo Games »</a>
<ul>
<li><a href="#">Board Games</a></li>
<li><a href="#">Card Games</a></li>
<li><a href="#">Puzzle Games</a></li>
<li><a href="#">Skill Games »</a>
<ul>
<li><a href="#">Yahoo Pool</a></li>
<li><a href="#">Chess</a></li>
</ul>
</li>
</ul>
</li>
<li><a href="#">Yahoo Search</a></li>
<li><a href="#">Yahoo Answsers</a></li>
</ul>
</li>
<li class="google"><a href="#">Google</a>
<ul>
<li><a href="#">Google mail</a></li>
<li><a href="#">Google Plus</a></li>
<li><a href="#">Google Search »</a>
<ul>
<li><a href="#">Search Images</a></li>
<li><a href="#">Search Web</a></li>
</ul>
</li>
</ul>
</li>
<li class="twitter"><a href="#">Twitter</a>
<ul>
<li><a href="#">New Tweets</a></li>
<li><a href="#">Compose a Tweet</a></li>
</ul>
</li>
</ul>
|
[
"stackoverflow",
"0049320114.txt"
] | Q:
How pass json Object string to javascript function?
i want to pass object json string to javascript function but facing some error. please help. thanks in advance. i'm using MVC5,
my code as below
inside .cshtml
<a href="javascript:void(0);" onclick="addToOrder('@JsonConvert.SerializeObject(item)')">@item.NAME</a>
my json value is inside addToOrder() function looks like,
{
"ITEM_ID": 1,
"NAME": "PEPPER POPPERS",
"FOOD_TYPE": "VEG",
"SIZES": [
{
"SIZE": "FULL",
"PRICE": 220.00
},
{
"SIZE": "MEDIUM",
"PRICE": 170.00
},
{
"SIZE": "8\"",
"PRICE": 50.00
},
{
"SIZE": "12\"",
"PRICE": 40.00
}]
}
throw error when JSON.parse "SIZE": "8\"" in javascript function!
Error in browser console
Uncaught SyntaxError: Unexpected string in JSON at position 37
at JSON.parse (<anonymous>)
at addToOrder (restaurantCounter.js:130)
at HTMLAnchorElement.onclick (1?deptid=6&counterid=1&department=1 AC:933)
Please help. thank you.
A:
The problem is with the json itself. Try this one
{
"ITEM_ID": 1,
"NAME": "PEPPER POPPERS",
"FOOD_TYPE": "VEG",
"SIZES": [
{
"SIZE": "FULL",
"PRICE": 220.00
},
{
"SIZE": "MEDIUM",
"PRICE": 170.00
},
{
"SIZE": "8\"",
"PRICE": 50.00
},
{
"SIZE": "12\"",
"PRICE": 40.00
}]
}
|
[
"stackoverflow",
"0010256677.txt"
] | Q:
Allocating a large amount of space for vector
I need to allocate a vector with 6227020800 elements. Its obviously too big for a regular call:
vector<int> largevector(6227020800)
I tried using new and its even too big for that:
vector<int> largevector= new vector<int>[6227020800]
Is there a way to allocate a vector that large?
A:
Take a look at the stxxl library.
|
[
"superuser",
"0001127299.txt"
] | Q:
How to restart MySQL with --skip-grant-tables if you can't use the root password?
I need to restart MySQL in Ubuntu 16.04 with the --skip-grant-tables option enabled, but either I don't know my root password or it isn't working. How can I set --skip-grant-tables without the password?
When I try it as a regular user:
mysqld --skip-grant-tables
I see this:
mysqld: Can't change dir to '/var/lib/mysql/' (Errcode: 13 - Permission denied)
So, I dug this example out of /etc/init.d/mysql and added the --skip-grant-tables parameter:
su - mysql -s /bin/bash -c "/usr/sbin/mysqld --skip-grant-tables"
Password:
su: Authentication failure
So su doesn't work and the root password didn't work either. I also tried this:
sudo su - mysql -s /bin/bash -c "/usr/sbin/mysqld --skip-grant-tables"
No directory, logging in with HOME=/
How can I start mysql with --skip-grant-tables?
A:
When you don't know your root password (or an error like 'ERROR 1045 (28000): Access denied for user 'root'@'localhost' prevents access) you can get access by adding the option to the MySQL config file. First open it for editing:
sudo nano /etc/mysql/my.cnf
Then search for [mysqld] and enter these values below it:
[mysqld]
# For debugging and recovery only #
skip-grant-tables
skip-networking
###################################
As you can see, the trick to adding command line parameters here is dropping the -- from the front of the parameter. Now restart the mysql service and you can access your tables to reset your root user password or almost anything you need to do. (However, you can't do anything with the grant tables because they aren't loaded.)
Beware. While you're in this mode, any logged-in user has access to your whole database. That's why I added the skip-networking option above, so remote users can't access the tables while you're recovering.
Be sure to comment out those lines out and restart mysql once again when you're done, to re-secure the server.
|
[
"gamedev.stackexchange",
"0000032357.txt"
] | Q:
Way to render objects
Is it best to have a renderer class in which you have a seperate function for each object you wish to draw? Or is it best to give each object a render function?
class Renderer {
...
}
Renderer::renderPlayer(Player *player) {
...
}
vs
class Player {
...
}
Player::render() {
...
}
A:
The question is a little bit vague and philosophical, im not sure it belongs to this website model, but here goes my opinion.
I would go with the first option, its my favourite way for the following reasons:
The drawable object should not be able to know everything about how to draw itself, instead, a global(or not so global) renderer should be used as a dependency for all drawables, to influence how they are drawn.
If a drawable only has geometry data in its raw form, that allows global configurations in the renderer to influence all geometry, instead of changing all one by one. Also it may allow optimizations that would be otherwise impossible, if all geometry and draw code was hidden behind each drawable.
One example that comes to mind would be the ability to batch all geometry that uses a same texture, and have it draw as fast as it possible, with less state changes.
Sorry for the possible incorrectness, my sleepiness is winning , cheers
|
[
"stackoverflow",
"0054897085.txt"
] | Q:
Getting top counts in a single query in bigquery
Suppose I have the following two fields:
`name` `age`
"tom" 20
"tom" 20
"brad" 10
"steve" 14
"alex" 13
"alex" 11
I want to populate a filter panel on my Page that gives the top count per field. For example, it would look like:
name (top 2)
----------------
Alex (2)
Tom (2)
age (top 2)
----------------
20 (2)
10 (1)
Normally I would do this with two queries:
SELECT name, count(*) FROM mytable GROUP BY name ORDER BY count(*) DESC LIMIT 2;
SELECT age, count(*) FROM mytable GROUP BY age ORDER BY count(*) DESC LIMIT 2
However, there may literally be hundreds of columns, so I do not want to do 100s of queries just to load the Filters panel. Is there a way to do the above in a single query? It needs to be exact results, so it cannot use something like APPROX_TOP_COUNT (unless you can specify 100% precision) on it.
How would I construct the above query?
Perhaps the following query would work, but how do I ensure that the results and counts will be exact?
select APPROX_TOP_COUNT(name, 2), APPROX_TOP_COUNT(age, 2) from `mytable`
The reason I need exact is because there may be financial data here, and for example, I need to give an exact count of "units sold" or something similar in the side panel.
A:
Below is for BigQuery Standard SQL
#standardSQL
SELECT
ARRAY(SELECT REGEXP_REPLACE(name, r'\(0*', '(') FROM t.names name ORDER BY name DESC) names,
ARRAY(SELECT REGEXP_REPLACE(age, r'\(0*', '(') FROM t.ages age ORDER BY age DESC) ages
FROM (
SELECT
ARRAY_AGG(DISTINCT name ORDER BY name DESC LIMIT 2) names,
ARRAY_AGG(DISTINCT age ORDER BY age DESC LIMIT 2) ages
FROM (
SELECT
CONCAT('(', SUBSTR(CONCAT('00000', CAST(COUNT(1) OVER(PARTITION BY name) AS STRING)), -5), ') ', name) name,
CONCAT('(', SUBSTR(CONCAT('00000', CAST(COUNT(1) OVER(PARTITION BY age) AS STRING)), -5), ') ', CAST(age AS STRING)) age
FROM `project.dataset.table`
)
) t
You can test, play with above using sample data from your question as in below example
#standardSQL
WITH `project.dataset.table` AS (
SELECT 'tom' name, 20 age UNION ALL
SELECT 'tom', 20 UNION ALL
SELECT 'brad', 10 UNION ALL
SELECT 'steve', 14 UNION ALL
SELECT 'alex', 13 UNION ALL
SELECT 'alex', 11
)
SELECT
ARRAY(SELECT REGEXP_REPLACE(name, r'\(0*', '(') FROM t.names name ORDER BY name DESC) names,
ARRAY(SELECT REGEXP_REPLACE(age, r'\(0*', '(') FROM t.ages age ORDER BY age DESC) ages
FROM (
SELECT
ARRAY_AGG(DISTINCT name ORDER BY name DESC LIMIT 2) names,
ARRAY_AGG(DISTINCT age ORDER BY age DESC LIMIT 2) ages
FROM (
SELECT
CONCAT('(', SUBSTR(CONCAT('00000', CAST(COUNT(1) OVER(PARTITION BY name) AS STRING)), -5), ') ', name) name,
CONCAT('(', SUBSTR(CONCAT('00000', CAST(COUNT(1) OVER(PARTITION BY age) AS STRING)), -5), ') ', CAST(age AS STRING)) age
FROM `project.dataset.table`
)
) t
with result
Row names ages
1 (2) tom (2) 20
(2) alex (1) 14
Update for I'd like to have it as an array (exactly as it would be in select APPROX_TOP_COUNT(name, 2), APPROX_TOP_COUNT(age, 2) from mytable)
See below - just two lines in outer SELECT are changed
#standardSQL
WITH `project.dataset.table` AS (
SELECT 'tom' name, 20 age UNION ALL
SELECT 'tom', 20 UNION ALL
SELECT 'brad', 10 UNION ALL
SELECT 'steve', 14 UNION ALL
SELECT 'alex', 13 UNION ALL
SELECT 'alex', 11
)
SELECT
ARRAY(SELECT STRUCT(REGEXP_EXTRACT(name, r'\(\d*\) (.*)') AS value, CAST(REGEXP_EXTRACT(name, r'\((\d*)\)') AS INT64) AS `count`) FROM t.names name ORDER BY name DESC) names,
ARRAY(SELECT STRUCT(REGEXP_EXTRACT(age, r'\(\d*\) (.*)') AS value, CAST(REGEXP_EXTRACT(age, r'\((\d*)\)') AS INT64) AS `count`) FROM t.ages age ORDER BY age DESC) ages
FROM (
SELECT
ARRAY_AGG(DISTINCT name ORDER BY name DESC LIMIT 2) names,
ARRAY_AGG(DISTINCT age ORDER BY age DESC LIMIT 2) ages
FROM (
SELECT
CONCAT('(', SUBSTR(CONCAT('00000', CAST(COUNT(1) OVER(PARTITION BY name) AS STRING)), -5), ') ', name) name,
CONCAT('(', SUBSTR(CONCAT('00000', CAST(COUNT(1) OVER(PARTITION BY age) AS STRING)), -5), ') ', CAST(age AS STRING)) age
FROM `project.dataset.table`
)
) t
with result
Row names.value names.count ages.value ages.count
1 tom 2 20 2
alex 2 14 1
|
[
"stackoverflow",
"0030733893.txt"
] | Q:
Why the script does NOT show "Fatal error: Maximum execution time of XX seconds"?
I would like to know why php (I'm using 5.5) doesn't stop this script with a fatal error. Thanks.
<?
set_time_limit(5);
ini_set('max_execution_time', 5);
echo 'hi';
for ($i = 0; $i < 10; $i++){
sleep(1);
}
echo '<br>bye';
?>
The output of the script is:
hi<br>bye
Without any errors or warnings.
A:
From the PHP docs:
The set_time_limit() function and the configuration directive max_execution_time only affect the execution time of the script itself. Any time spent on activity that happens outside the execution of the script such as system calls using system(), stream operations, database queries, etc. is not included when determining the maximum time that the script has been running. This is not true on Windows where the measured time is real.
To paraphrase this documentation answer, it basically means that sleep() is not a time consuming function in Linux.
|
[
"stackoverflow",
"0052060174.txt"
] | Q:
AngularJS adal Authentication to Azure Blob Storage
I have an angularJS project. I've included azure-blob-storage.js in my scripts and I am able to get access using SAS but not the AD authentication.
I have added Azure Storage API permissions to the AD App Registration and given the App Reader and Contributor roles to the storage account.
adalAuthenticationService.acquireToken({clientId},
function(error, token) {
// Handle ADAL Error
if (error || !token) {
return;
}
}).then(function (token) {
var tokenCredential = new AzureStorage.Blob.TokenCredential(token);
var blobService = AzureStorage.Blob.createBlobServiceWithTokenCredential({myStorageAccountURI}, tokenCredential);
I get the following error:
<Error><Code>AuthenticationFailed</Code><Message>Server failed to authenticate the request. Make sure the value of Authorization header is formed correctly including the signature....</Message>
<AuthenticationErrorDetail>Audience validation failed. Audience did not match.</AuthenticationErrorDetail></Error>
A:
The error Audience validation failed. Audience did not match. means the token audience (= intended receiver) is wrong. You are most likely acquiring a token for your app with your client id. You need to switch it to https://storage.azure.com/ in the call to acquireToken().
And also your user needs to have the read/write access to the blobs as you found out :)
|
[
"math.stackexchange",
"0003430461.txt"
] | Q:
Let $P(z)=\displaystyle{\sum}_{k=0}^{n}a_kz^k$ with $a_0,...,a_n\in\mathbb{R}$ Prove if $P(\alpha)=0$ then $P(\bar{\alpha})=0$
Let $P(z)=\displaystyle{\sum}_{k=0}^{n}a_kz^k$ with $a_0,...,a_n\in\mathbb{R}$ Prove if $P(\alpha)=0$ then $P(\bar{\alpha})=0$
My attempt:
Let $\alpha\in\mathbb{C}$ such that $\alpha=x+iy$. Let $\bar{\alpha}$ the conjugate of alpha
$\displaystyle{\sum}_{k=0}^{n}a_kz^k=0$ implies that $a_0+a_1z+...a_nz^n=0$
Here i'm stuck. can someone help me?
A:
You should use the following properties for $z, w \in \mathbb C$:
$$\overline {zw} = \bar z \bar w$$
$$\overline {z + w} = \overline z + \overline w$$
|
[
"stackoverflow",
"0003801757.txt"
] | Q:
fast querying on hbase
I am running a little test/poc here.
I need to load a few million rows every day into a database. And it's not log file data, I have comma delimited rows (of columns) which would exactly fit a relational database.
After the loading, I need to allow a very fast search mechanism. Looking a bit at Google's implementation of bigtable and structure around it, I originally thought of using hive integrated with hbase. Hive because of its querying capabilities. The loading works out fine, better than RDBMS perf. However, the querying bottleneck, which was the reason to look for alternatives to RDBMS in the first place, continues with hive too.
Testing hive for querying is not really blazing performance. Perhaps I need to look for alternatives..
Is there something else ? any other tool/solution/library that I can put on top of hbase ? or even without hbase ? (I looked at hbase as an alternative to the RDBMS, moving towards dist computing)
Suggestions please...
A:
If you want general search capabilities you may want to look at solutions like Solr or ElasticSearch instead. HBase works well if you prepare the data for the queries you need (key design) not for general search. Also you can look at Lily which combines Solr and HBase
|
[
"stackoverflow",
"0036532799.txt"
] | Q:
Android - Backendless: Issue with like button
Coming here from backendless support forum. "This support forum is strictly for Backendless-related issues. Any general problems outside of our APIs and backend services are not covered by support. Please consider posting to stackoverflow.com and/or Android forums." Mark Piller.
So I'm posting my problem here.
At backendless support forum I got some precious help to save and retrieve relations but now I'm facing another problem with the Like button.
I'm working on a social app in which there are 3 button: Like Comment Share.
Link at my backendless support thread:
http://support.backendless.com/topic/some-questions-regarding-data-loading-in-recyclerview-android
For now I'm trying to make Like button work but I'm facing the following problem:
If you look at the following code and at the screenshot I attached you can see that there's the like heart button which isn't fill and it means I didn't hit the like for that post. And at 2 number there's another button which is filled and I hit liked on it and the app added me to the list of users those like that post.
if (user.getObjectId().equals(userId)) {
holder.like.setBackgroundResource(R.drawable.ic_star_rate_on);
holder.like.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
showToast();
}
});
} else {
holder.like.setBackgroundResource(R.drawable.ic_star_rate_off);
//onclick in another function: setLike(holder.like,holder.likes,feeds);
}
But the problem is that the click on the empty heart isn't working. I tried to create a toast to check if click works and the toast isn't showing up.
But if I click on an item which I liked (with heart icon filled) it shows me the toast which I put to check if it listens to my click....
I tried to debug the app and nothing appears in the debug window... everything seems to be normal but can't find out what's the problem with the code.
My Adapter class is following:
public class FeedAdapter extends RecyclerView.Adapter<FeedAdapter.FeedsHolder> {
private List<Feeds> list;
private Context context;
private static String TAG = "MainActivity";
public FeedAdapter(Context context, List<Feeds> list) {
this.context = context;
this.list = list;
}
@Override
public FeedsHolder onCreateViewHolder(ViewGroup parent, int viewType) {
View view = LayoutInflater.from(parent.getContext()).inflate(R.layout.feed_item, parent, false);
return new FeedsHolder(view);
}
@Override
public void onBindViewHolder(final FeedsHolder holder, int position) {
//Starting Feeds
final Feeds feeds = list.get(position);
//Name
holder.name.setText(feeds.getOwner());
//Profile picture
holder.profilePictureURL = feeds.getProfilePictureURL();
//Image
holder.imageURL = feeds.getImageUrl();
//Getting date
Date myD = feeds.getCreated();
long ddate = myD.getTime();
String myDate = String.valueOf(DateUtils.getRelativeTimeSpanString(ddate, System.currentTimeMillis(), DateUtils.SECOND_IN_MILLIS));
holder.timeAgo.setText("• " + myDate);
//Get total likes
final int i = feeds.getLikes();
//Query
QueryOptions options = new QueryOptions();
options.setRelated( Arrays.asList( "usersThatLike" ) );
BackendlessDataQuery query = new BackendlessDataQuery();
query.setQueryOptions( options );
// getting all saved feeds with related users
Backendless.Data.of(Feeds.class).find(query, new AsyncCallback<BackendlessCollection<Feeds>>() {
@Override
public void handleResponse(BackendlessCollection<Feeds> response) {
String userId = Backendless.UserService.CurrentUser().getObjectId();
for (Feeds feed: response.getCurrentPage()) {
List<BackendlessUser> likedUsers = feeds.getUsersThatLike();
for (BackendlessUser user : likedUsers)
if (user.getObjectId().equals(userId)) {
Log.d(TAG, "No -------------------------------------");
holder.like.setBackgroundDrawable(context.getResources().getDrawable(R.drawable.ic_star_rate_on));
holder.like.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
Toast.makeText(context, "You already like this item", Toast.LENGTH_SHORT).show();
}
});
} else {
holder.like.setBackgroundDrawable(context.getResources().getDrawable(R.drawable.ic_star_rate_off));
holder.like.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
Log.d(TAG, "It should work +++++++++++++++++++++++++++++++");
// getting current user
Toast.makeText(context, "Arrived", Toast.LENGTH_SHORT).show();
BackendlessUser currentUser = Backendless.UserService.CurrentUser();
// adding current user as one who "liked" feed, you should implement "adding" by yourself
List<BackendlessUser> list = new ArrayList<>();
list.add(currentUser);
feeds.setUsersThatLike(list);
holder.like.setBackgroundDrawable(context.getResources().getDrawable(R.drawable.ic_star_rate_on));
feeds.setLikes(i + 1);
Backendless.Data.of(Feeds.class).save(feeds, new AsyncCallback<Feeds>() {
@Override
public void handleResponse(Feeds feeds) {
int likes = feeds.getLikes();
if (likes == 1) {
holder.likes.setText(i + 1 + " like");
} else {
holder.likes.setText(i + 1 + " likes");
}
}
@Override
public void handleFault(BackendlessFault backendlessFault) {
}
});
}
});
}
}
}
@Override
public void handleFault(BackendlessFault backendlessFault) {
}
});
holder.status.setText(feeds.getStatus());
String thisString = "no";
String myImageString = "no";
Picasso.with(context).load(holder.profilePictureURL).placeholder(R.drawable.placeholder).into(holder.profilePicture);
String image = feeds.getIsImageUrlEmpty();
if (!image.equals(myImageString)) {
holder.image.setVisibility(View.GONE);
holder.tagStatusBottom.setVisibility(View.VISIBLE);
holder.tagImageBottom.setVisibility(View.GONE);
} else {
holder.image.setVisibility(View.VISIBLE);
holder.tagStatusBottom.setVisibility(View.GONE);
holder.tagImageBottom.setVisibility(View.VISIBLE);
Picasso.with(context).load(holder.imageURL).placeholder(R.drawable.placeholder).into(holder.image);
}
String myString = feeds.getIsTagEmpty();
if (myString.equals(thisString)){
holder.tagImageBottom.setVisibility(View.VISIBLE);
if (!image.equals(myImageString)) {
holder.image.setVisibility(View.GONE);
holder.tagStatusBottom.setVisibility(View.VISIBLE);
holder.tagImageBottom.setVisibility(View.GONE);
} else {
holder.image.setVisibility(View.VISIBLE);
holder.tagStatusBottom.setVisibility(View.GONE);
holder.tagImageBottom.setVisibility(View.VISIBLE);
Picasso.with(context).load(holder.imageURL).placeholder(R.drawable.placeholder).into(holder.image);
}
} else {
holder.tagImageBottom.setVisibility(View.GONE);
holder.tagStatusBottom.setVisibility(View.GONE);
}
String str = feeds.getTag();
ArrayList<int[]> hashtagSpans1 = getSpans(str, '#');
SpannableString commentsContent1 =
new SpannableString(str);
setSpanComment(commentsContent1, hashtagSpans1) ;
holder.tagImageBottom.setText(commentsContent1);
holder.tagStatusBottom.setText(commentsContent1);
holder.tagImageBottom.setMovementMethod(LinkMovementMethod.getInstance());
int likes = feeds.getLikes();
if (likes == 1) {
holder.likes.setText(i +" like");
} else {
holder.likes.setText(i +" likes");
}
}
public ArrayList<int[]> getSpans(String body, char prefix) {
ArrayList<int[]> spans = new ArrayList<int[]>();
Pattern pattern = Pattern.compile(prefix + "\\w+");
Matcher matcher = pattern.matcher(body);
// Check all occurrences
while (matcher.find()) {
int[] currentSpan = new int[2];
currentSpan[0] = matcher.start();
currentSpan[1] = matcher.end();
spans.add(currentSpan);
}
return spans;
}
private void setSpanComment(SpannableString commentsContent, ArrayList<int[]> hashtagSpans) {
for(int i = 0; i < hashtagSpans.size(); i++) {
int[] span = hashtagSpans.get(i);
int hashTagStart = span[0];
int hashTagEnd = span[1];
commentsContent.setSpan(new Hashtag(context),
hashTagStart,
hashTagEnd, 0);
}
}
@Override
public int getItemCount() {
return list.size();
}
And here is my Feed class:
public class Feeds
{
private String owner;
private String tag;
private String profilePictureURL;
private String imageURL;
private Date created;
private Date updated;
private String status;
private int likes;
private String isTagEmpty;
private String isImageUrlEmpty;
private List<BackendlessUser> usersThatLike;
public String getOwner()
{
return owner;
}
public void setOwner( String owner )
{
this.owner = owner;
}
public int getLikes()
{
return likes;
}
public void setLikes ( int likes )
{
this.likes = likes;
}
public String getIsTagEmpty()
{
return isTagEmpty;
}
public void setIsTagEmpty ( String isTagEmpty )
{
this.isTagEmpty = isTagEmpty;
}
public String getIsImageUrlEmpty()
{
return isImageUrlEmpty;
}
public void setIsImageUrlEmpty ( String isImageUrlEmpty )
{
this.isImageUrlEmpty = isImageUrlEmpty;
}
public String getStatus()
{
return status;
}
public void setStatus( String status )
{
this.status = status;
}
public String getTag()
{
return tag;
}
public void setTag( String tag )
{
this.tag = tag;
}
public String getProfilePictureURL()
{
return profilePictureURL;
}
public void setProfilePictureURL ( String profilePictureURL )
{
this.profilePictureURL = profilePictureURL;
}
public String getImageUrl()
{
return imageURL;
}
public void setImageUrl ( String imageURL )
{
this.imageURL = imageURL;
}
public Date getCreated()
{
return created;
}
public Date getUpdated()
{
return updated;
}
public List<BackendlessUser> getUsersThatLike() {
return usersThatLike;
}
public void setUsersThatLike(List<BackendlessUser> usersThatLike) {
this.usersThatLike = usersThatLike;
}
}
Can you help me with it?
EDIT: After implementing code in the answer below it doesn't work. This is how I edited my code:
//Skipped previous code. Posted only the changed code
Backendless.Data.of(Feeds.class).find(query, new AsyncCallback<BackendlessCollection<Feeds>>() {
@Override
public void handleResponse(final BackendlessCollection<Feeds> feedsBackendlessCollection) {
//Suggested by sihao
holder.like.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
String userId = Backendless.UserService.CurrentUser().getObjectId();
for (Feeds feed: feedsBackendlessCollection.getCurrentPage()) {
List<BackendlessUser> likedUsers = feeds.getUsersThatLike();
for (BackendlessUser user : likedUsers)
if (user.getObjectId().equals(userId)) {
Toast.makeText(context,"You already liked this item",Toast.LENGTH_SHORT).show();
} else {
// getting current user
BackendlessUser currentUser = Backendless.UserService.CurrentUser();
// adding current user as one who "liked" feed, you should implement "adding" by yourself
List<BackendlessUser> list = new ArrayList<>();
list.add(currentUser);
feeds.setUsersThatLike(list);
holder.like.setBackgroundDrawable(context.getResources().getDrawable(R.drawable.ic_star_rate_on));
feeds.setLikes(i + 1);
Backendless.Data.of(Feeds.class).save(feeds, new AsyncCallback<Feeds>() {
@Override
public void handleResponse(Feeds feeds) {
int likes = feeds.getLikes();
if (likes == 1) {
holder.likes.setText(i + 1 + " like");
} else {
holder.likes.setText(i + 1 + " likes");
}
}
@Override
public void handleFault(BackendlessFault backendlessFault) {
}
});
}
}
}
});
}
@Override
public void handleFault(BackendlessFault backendlessFault) {
}
});
UPDATE: I tried to solve the issue in these days and got an (nice) idea.
I'm successfully changing the buttons background from empty heart to fill heart for the elements that has been likes by users. I got the following idea: Check if the heart is empty or fill. So on activity load my app gets data from the "usersThatLike" column and set fill heart drawable if user is present in the list on backendless and empty heart drawable if it isn't there.
So now I'm trying to create a check on the drawable.
If heart is filled than show the toast "You liked this item already" else put the like to the item and add the user to "usersThatLike" column for current item.
But it's returning "filled" heart for all the items. I mean to say, even if the heart drawable is empty it is returning that it's filled and if I click a filled heart drawable than it will show the toast but if the heart isn't filles it will show the same toast:
My code is:
//*** Skipped the query code. In handleResponse:
String userId = Backendless.UserService.CurrentUser().getObjectId();
for (Feeds feed: response.getData()) {
feed = list.get(position);
List<BackendlessUser> likedUsers = feed.getUsersThatLike();
for (BackendlessUser user : likedUsers)
if (user.getObjectId().equals(userId)) {
holder.like.setBackgroundResource(R.drawable.ic_star_rate_on);
} else if (!user.getObjectId().equals(userId)) {
holder.like.setBackgroundResource(R.drawable.ic_star_rate_off);
}
}
And than out of the handleResponse, in normal onBindViewHolder after the query code I'm checking the drawable like this:
//***HERE IS THE QUERY
Backendless.Data.of(Feeds.class).find(query, new AsyncCallback<BackendlessCollection<Feeds>>() {
//***SKIPPED FOR BREVITY
});
//***HERE IS THE CHECK
holder.like.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
if (holder.like.getBackground() != context.getDrawable(R.drawable.ic_star_rate_off)){
toast();
} else {
setLike();
}
}
});
A:
UPDATE:
Hello guys,
I finally found a great tricky solution to my problem.
I was able to save the user to "usersThatLike" column and set the like on the certain item. But every time I clicked like button it was showing the toast "You already liked it" which should be shown only if I was present in the list of usersThatLike so there was the problem.
I used the following trick to get rid of this problem:
In my RecyclerView adapter I queried my class like this:
QueryOptions options = new QueryOptions();
options.setRelated( Arrays.asList( "usersThatLike" ) );
BackendlessDataQuery query = new BackendlessDataQuery();
query.setQueryOptions( options );
Backendless.Data.of(Feeds.class).find(query, new AsyncCallback<BackendlessCollection<Feeds>>() {
@Override
public void handleResponse(BackendlessCollection<Feeds> response) {
String userId = Backendless.UserService.CurrentUser().getObjectId();
for (Feeds feed: response.getData()) {
feed = list.get(position);
List<BackendlessUser> likedUsers = feed.getUsersThatLike();
for (BackendlessUser user : likedUsers)
if (user.getObjectId().equals(userId)) {
holder.like.setBackgroundResource(R.drawable.ic_star_rate_on);
} else if (!user.getObjectId().equals(userId)) {
holder.like.setBackgroundResource(R.drawable.ic_star_rate_off);
}
}
}
@Override
public void handleFault(BackendlessFault backendlessFault) {
}
});
As you can see I set the drawable with star off if query returns that user isn't in the list and on if the user is there.
So after that here is how I was able to resolve the problem.
Outside of my query I created the following check:
holder.likeLayout.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
if (holder.like.getBackground().getConstantState() != ContextCompat.getDrawable(context, R.drawable.ic_star_rate_off).getConstantState()){
toast();
} else {
setLike();
}
}
});
In code above I get the button background and compare it to the image present in my drawable folder with star off.
if the like button is with star_off it will set the like and add user to the usersThatLike list. Otherwise show a toast: "You already liked this item"
Hope it can help others and save their time as I have spent lot of time on this issue.
Regards
Old Answer:
Answering to sihao's comment :
@sihao if you check my first post you will see:
if (user.getObjectId().equals(userId)) {
Log.d(TAG, "No -------------------------------------");
holder.like.setBackgroundDrawable(context.getResources().getDrawable(R.drawable.ic_star_rate_on));
// FIRST ONCLICK LISTENER
holder.like.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
Toast.makeText(context, "You already like this item", Toast.LENGTH_SHORT).show();
}
});
} else {
holder.like.setBackgroundDrawable(context.getResources().getDrawable(R.drawable.ic_star_rate_off));
// SECOND ONCLICK LISTENER
holder.like.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
Log.d(TAG, "It should work +++++++++++++++++++++++++++++++");
// getting current user
Toast.makeText(context, "Arrived", Toast.LENGTH_SHORT).show();
BackendlessUser currentUser = Backendless.UserService.CurrentUser();
// adding current user as one who "liked" feed, you should implement "adding" by yourself
List<BackendlessUser> list = new ArrayList<>();
list.add(currentUser);
feeds.setUsersThatLike(list);
holder.like.setBackgroundDrawable(context.getResources().getDrawable(R.drawable.ic_star_rate_on));
feeds.setLikes(i + 1);
Backendless.Data.of(Feeds.class).save(feeds, new AsyncCallback<Feeds>() {
@Override
public void handleResponse(Feeds feeds) {
int likes = feeds.getLikes();
if (likes == 1) {
holder.likes.setText(i + 1 + " like");
} else {
holder.likes.setText(i + 1 + " likes");
}
}
@Override
public void handleFault(BackendlessFault backendlessFault) {
}
});
}
});
|
[
"blender.stackexchange",
"0000084167.txt"
] | Q:
What's the fastest way to turn a triangular face into three quads?
What's the fastest way to turn a triangular face into three quads?
A:
Subdivide triangle. Select face of middle triangle. Repeat. Select inner vertices and use AltM to merge at centre.
My 5 cents. What's yours?
p.s. no need to go into vertex mode. Face select and AltM is enough.
A:
Subdivision Surface modifier with Simple mode
Just add to your object a subdivision surface modifier from the list and choose the Simple option.
This method is obviously not good if you would like to subdivide only a subset of faces of your object as the modifier is being applied to the whole object (in this case made of a single face).
A:
I guess you could always use the shortcut and not model it all. :)
The Add Mesh Extra Objects Add-On has been updated in version 2.79 and now includes a triangle object. It is found under Add Mesh>Math Function>Triangle. There are options for 3 and 6 quad faces, and 3 tri faces.
If you do not have it enabled already, just enable it in user preferences with Ctrl+Alt+U and search for 'extra'.
Here is an example gif:
|
[
"stackoverflow",
"0005841371.txt"
] | Q:
Body Interactive Images using .Net
what is the best way to View Body Parts in Interactive Way in ASP.Net and also in WinForms
When Mouse over any part of the body it's color will changed, then user can click and add notes about this part?
what about using SVG files for body parts, is there any already SVG for body parts.
what about Flash , OR WPF..
what is the best i can use , Is there any already Tools or controls i can use ..
A:
I found these useful links.
http://www.biodigitalhuman.com/
http://www.visiblebody.com/demos/head/head_region_demo.html
http://davidlynch.org/js/maphilight/docs/demo_world.html
|
[
"stackoverflow",
"0010030964.txt"
] | Q:
Ways to post query data to URL without a form?
I need to pass a couple bits of info through the URL just by clicking a link, rather than by using action="GET" with a form and input button. Is this possible? This is client-side only, there is no server, so suggestions regarding PHP etc. will not be useful in this circumstance.
A:
In your anchor, change the href to include a querystring at the end.
e.g.
<a href="http://www.example.com/test.html?parameter=2">
A:
Assuming you have access to the variables on the client, you can do something like this:
<script type="text/javascript">
navigateToPage = function(val){
window.location.href = "/somefolder/somefile.htm?id=" + val;
}
</script>
<input type="button" value="Navigate" onclick="navigateToPage(5);" />
A:
You're gonna need to use JavaScript to get all the values, and then combine them into a URL.
Here's an example (using the jQuery library):
<a href="http://example.com/test.html" id="paramLink">Click</a>
<script>
$(function(){
// The data, from the page
var id = 1, name = 'test';
// Add event to link
$('#paramLink').click(function(e){
e.preventDefault(); // Stop the browser from following the link
location.href = $(this).attr('href')+'?id='+id+'&name='+name; // Build the URL
});
});
</script>
|
[
"stackoverflow",
"0015618062.txt"
] | Q:
Check if value is multiple of 10
I want to check if a value is a multiple of a certain number, for example, multiples of 10, but I also want to be able to change it to whatever I want.
if (directWinner == 10){
}
A:
You'd use the modulus operator for that :
if (directWinner % 10 === 0){
directWinner = 20;
}
Added a small dose of jQuery for no good reason at all ?
$.modu = function(check, against) {
return check % against === 0;
}
if ( $.modu(directWinner, 10) ) {
directWinner = 20;
}
|
[
"stackoverflow",
"0007051405.txt"
] | Q:
Show 'Total Of' in Window
I wonder whether someone may be able to help me please.
I am using the code below to correctly show markers for all the locations stored in mySQL database.
PHP
<?php
require("phpfile.php");
// Start XML file, create parent node
$dom = new DOMDocument("1.0");
$node = $dom->createElement("markers");
$parnode = $dom->appendChild($node);
// Opens a connection to a MySQL server
$connection=mysql_connect ("hostname", $username, $password);
if (!$connection) { die('Not connected : ' . mysql_error());}
// Set the active MySQL database
$db_selected = mysql_select_db($database, $connection);
if (!$db_selected) {
die ('Can\'t use db : ' . mysql_error());
}
// Select all the rows in the markers table
Amended Code
$query = "select l.locationname, l.address, l.osgb36lat, l.osgb36lon, count(*) as totalfinds from locations as l left join finds as f on l.locationid=f.locationid";
$result = mysql_query($query);
if (!$result) {
die('Invalid query: ' . mysql_error());
}
header("Content-type: text/xml");
// Iterate through the rows, adding XML nodes for each
while ($row = @mysql_fetch_assoc($result)){
// ADD TO XML DOCUMENT NODE
$node = $dom->createElement("marker");
$newnode = $parnode->appendChild($node);
$newnode->setAttribute("locationname",$row['locationname']);
$newnode->setAttribute("address",$row['address']);
$newnode->setAttribute("osgb36lat",$row['osgb36lat']);
$newnode->setAttribute("osgb36lon",$row['osgb36lon']);
$newnode->setAttribute("finds",$row['finds']);
$newnode->setAttribute("totalfinds",$row['totalfinds']);
}
}
echo $dom->saveXML();
?>
HTML
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" lang="en">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>Locations</title>
<link rel="stylesheet" href="css/alllocationsstyle.css" type="text/css" media="all" />
<script type="text/javascript" src="http://maps.google.com/maps/api/js?sensor=false&language=en"></script>
<script type="text/javascript">
var customIcons = {
0: {
icon: 'http://labs.google.com/ridefinder/images/mm_20_red.png',
shadow: 'http://labs.google.com/ridefinder/images/mm_20_shadow.png'
},
1: {
icon: 'http://labs.google.com/ridefinder/images/mm_20_green.png',
shadow: 'http://labs.google.com/ridefinder/images/mm_20_shadow.png'
}
};
function load() {
var map = new google.maps.Map(document.getElementById("map"), {
center: new google.maps.LatLng(54.312195845815246,-4.45948481875007),
zoom:6,
mapTypeId: 'roadmap'
});
var infoWindow = new google.maps.InfoWindow;
// Change this depending on the name of your PHP file
downloadUrl("phpfile.php", function(data) {
var xml = data.responseXML;
var markers = xml.documentElement.getElementsByTagName("marker");
for (var i = 0; i < markers.length; i++) {
var locationname = markers[i].getAttribute("locationname");
var address = markers[i].getAttribute("address");
var finds = markers[i].getAttribute("finds");
var totalfinds = markers[i].getAttribute("totalfinds");
var point = new google.maps.LatLng(
parseFloat(markers[i].getAttribute("osgb36lat")),
parseFloat(markers[i].getAttribute("osgb36lon")));
var html = "<b>" + locationname + "</b>";
var icon = customIcons[finds] || {};
var marker = new google.maps.Marker({
map: map,
position: point,
icon: icon.icon,
shadow: icon.shadow
});
bindInfoWindow(marker, map, infoWindow, html);
}
});
}
function bindInfoWindow(marker, map, infoWindow, html) {
google.maps.event.addListener(marker, 'click', function() {
infoWindow.setContent(html);
infoWindow.open(map, marker);
});
}
function downloadUrl(url, callback) {
var request = window.ActiveXObject ?
new ActiveXObject('Microsoft.XMLHTTP') :
new XMLHttpRequest;
request.onreadystatechange = function() {
if (request.readyState == 4) {
request.onreadystatechange = doNothing;
callback(request, request.status);
}
};
request.open('GET', url, true);
request.send(null);
}
function doNothing() {}
</script>
</head>
<body onLoad="load()">
<div id="map"></div>
</body>
</html>
What I would like to do is to adapt the coding whereby the 'Total number of finds' for each location is shown along with the 'Location Name' in the Infowindow that is created for each marker.
I know that I need to get this information from my table called 'finds' where I need to count the number of rows where the 'locationid' matches the one in the 'locations' table, but I must admit I haven't a clue how to do this.
I just wondered whether someone could perhaps please provide some guidance on what I need to do to achieve this.
Many thanks and kind regards
Chris
Finds SQL Dump
--
-- Table structure for table `finds`
--
DROP TABLE IF EXISTS `finds`;
CREATE TABLE IF NOT EXISTS `finds` (
`userid` int(6) NOT NULL,
`locationid` int(6) NOT NULL,
`findid` int(6) NOT NULL auto_increment,
`findosgb36lat` float(10,6) NOT NULL,
`findosgb36lon` float(10,6) NOT NULL,
`dateoftrip` varchar(8) NOT NULL,
`findname` varchar(35) NOT NULL,
`finddescription` varchar(100) NOT NULL,
`findimage` varchar(200) default NULL,
`additionalcomments` varchar(600) default NULL,
`makepublic` varchar(3) NOT NULL default 'no',
PRIMARY KEY (`findid`)
) ENGINE=MyISAM AUTO_INCREMENT=34 DEFAULT CHARSET=utf8 AUTO_INCREMENT=34 ;
Locations SQL dump
--
-- Table structure for table `locations`
--
CREATE TABLE `locations` (
`userid` int(6) NOT NULL,
`locationid` int(6) NOT NULL auto_increment,
`locationname` varchar(80) NOT NULL,
`address` varchar(110) NOT NULL,
`osgb36lat` float(10,6) NOT NULL,
`osgb36lon` float(10,6) NOT NULL,
`osgridref` varchar(20) NOT NULL,
`wgs84latd` int(2) NOT NULL,
`wgs84latm` int(2) NOT NULL,
`wgs84lats` decimal(6,2) NOT NULL,
`wgs84latb` varchar(1) NOT NULL,
`wgs84lond` int(2) NOT NULL,
`wgs84lonm` int(2) NOT NULL,
`wgs84lons` decimal(6,2) NOT NULL,
`wgs84lonb` varchar(1) NOT NULL,
`nameoflocationcontact` varchar(30) NOT NULL,
`locationcontactsaddressline1` varchar(50) NOT NULL,
`locationcontactsaddressline2` varchar(50) default NULL,
`locationcontactsaddressline3` varchar(50) default NULL,
`locationcontactsaddressline4` varchar(50) default NULL,
`locationcontactstelephonenumber` varchar(15) default NULL,
`finds` int(1) NOT NULL,
PRIMARY KEY (`locationid`)
) ENGINE=MyISAM AUTO_INCREMENT=27 DEFAULT CHARSET=utf8 AUTO_INCREMENT=27 ;
A:
You'd want to change the sql fetching code to join the finds table. Left join seems suitable for this.
Updated sql code:
select l.locationid, f.locationid, l.locationname, l.address,
l.osgb36lat, l.osgb36lon, l.finds, count(f.locationid) as totalfinds
from locations as l left join finds as f on l.locationid=f.locationid
group by l.locationid
You will now be able to get the total number of location finds in the total_finds element of the $row array. Also note I removed the where 1 condition in the original sql as it makes no sense.
Of course you'll also need save the total_finds value in the XML and make the appropriate changes in the JS code.
|
[
"stackoverflow",
"0027537798.txt"
] | Q:
How to Change CommandField ButtonType Image Width and Height
Hi I have a commandfield for deleting, and I gave it a DeleteImageURL but i do not know how to change the height and width of it and make it centered.
DeleteImageUrl="~/img/error.png"
Here is my gridview:
<asp:GridView ID="gvOrderDetail" runat="server" AutoGenerateColumns="False" CssClass="mGrid" PagerStyle-CssClass="pgr" AlternatingRowStyle-CssClass="alt" CellPadding="4" ForeColor="#333333" GridLines="None" Width="660px">
<AlternatingRowStyle BackColor="White" ForeColor="#284775" />
<Columns>
<asp:CommandField HeaderText="Action" ShowDeleteButton="True" ButtonType="Image" DeleteImageUrl="~/img/error.png" />
<asp:BoundField DataField="PartNumber" HeaderText="Part Number" />
<asp:BoundField DataField="Description" HeaderText="Description"></asp:BoundField>
<asp:BoundField DataField="Qty" HeaderText="Qty" >
<ItemStyle HorizontalAlign="Right" />
</asp:BoundField>
<asp:BoundField DataField="Price" HeaderText="Price" >
<ItemStyle HorizontalAlign="Right" />
</asp:BoundField>
<asp:BoundField DataField="ExtPrice" HeaderText="Ext Price" >
<ItemStyle HorizontalAlign="Right" />
</asp:BoundField>
</Columns>
<EditRowStyle BackColor="#999999" />
<FooterStyle BackColor="#5D7B9D" Font-Bold="True" ForeColor="White" />
<HeaderStyle BackColor="#5D7B9D" Font-Bold="True" ForeColor="White" />
<PagerStyle BackColor="#284775" ForeColor="White" HorizontalAlign="Center" />
<RowStyle BackColor="#F7F6F3" ForeColor="#333333" />
<SelectedRowStyle BackColor="#E2DED6" Font-Bold="True" ForeColor="#333333" />
<SortedAscendingCellStyle BackColor="#E9E7E2" />
<SortedAscendingHeaderStyle BackColor="#506C8C" />
<SortedDescendingCellStyle BackColor="#FFFDF8" />
<SortedDescendingHeaderStyle BackColor="#6F8DAE" />
</asp:GridView>
A:
You have a Style property that you can use for this purpose:
ControlStyle
ControlStyle
This applies css style through strongly-typed properties to the controls inside the data item. Here's an example of how to use it...
<asp:GridView...>
<Columns>
<asp:CommandField ControlStyle-Width="16px" ControlStyle-Height="16px" />
</Columns>
</asp:GridView>
Of course, this will apply the same style to all the controls inside the CommandField, so if you specify ShowEditButton=true and ShowDeleteButton=true in the CommandField both the delete and the edit button will share the same style. The bottom line is, this might be a bit limited if you need to have "total" control of these controls.
If you need to specify different styles for each control then you should use a TemplateField instead of a CommandField
|
[
"stackoverflow",
"0014563008.txt"
] | Q:
Embedding flv (flash) player in WPF app
Is there a method to embed ANY flash Player/activx to WPF application to play FLV files?
I am guessing also if it is possible to add some JS code to WPF WebBrowser control and play video there?
Is it good approach?
A:
If embed code contains an iframe, take the src of iframe and put it into WebBrowser source.
For example, for Youtube videos this is the embed code:
<iframe width="560" height="315"
src="http://www.youtube.com/embed/[youtubeVideoId]"
frameborder="0" allowfullscreen>
</iframe>
You will use this url in your WPF WebBrowser:
http://www.youtube.com/embed/[youtubeVideoID]
Similar for other sites.
|
[
"stackoverflow",
"0009151366.txt"
] | Q:
The tag 'XXX' does not exist in XML namespace 'clr-namespace:YYY'
I have implemented a converter to convert Int32 to String to be able to binding a property to a textBox.
I implement this converter in the namespace MyApp.Converters and it is called Int32ToStringConverter.
Then, in my axml I add the reference to my converter as follow:
<Window x:Class="MusicaDB.Views.PrincipalView"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:i="namespace:System.Windows.Interactivity;assembly=System.Windows.Interactivity"
**xmlns:converter="clr-namesapce:MyApp.Converters, aseembly=MyApp**">
Later, in windows.Resources I have:
<Window.Resources>
<**converter:Int32ToStringConverter** x:Key="Int32ToStringConverter" />
</Window.Resources>
I get the error that the tag Int32ToString converter does not exist in the namespace MyApp.Converters,assembly=MyApp.
I have the project in the local hard drive, in the project properties, the destination .NET is framework 4.0, not framework 4.0 client profile and I try to clear the solution and recompile but the problem persists.
Mainly, this is the two solutions that I always find, but don't resolve my problem.
A:
Another possible solution to this problem is that you're not using the same version of .Net in your project and your library.
A:
Three fixes to make here:
No spaces -> xmlns:converter="clr-namesapce:MyApp.Converters,aseembly=MyApp"
No misspellings -> xmlns:converter="clr-namespace:MyApp.Converters,assembly=MyApp"
Right delimiters -> xmlns:converter="clr-namespace:MyApp.Converters;assembly=MyApp"
From the the documentation:
Note that the character separating the clr-namespace token from its value is a colon (:) whereas the character separating the assembly token from its value is an equals sign (=). The character to use between these two tokens is a semicolon. Also, do not include any whitespace anywhere in the declaration.
A:
I am exploring as to why this is happening, but if your converter is in the main assembly, removing the assembly= from your xmlns:converters tag should remove that build error.
|
[
"stackoverflow",
"0011849306.txt"
] | Q:
Same binding works for 1 XAML item, but null for another
The binding for productColumn2 works perfect both ways. When I added a converter for each, productColumn1 called the converter; but always has it's value set to null when loading from observable collection, or value set to product when assigning (but doesn't actually assign observable collection).
Issue has to do with DataContext and LogicalTree. The DataContext for ProductSelectorTextBoxUserControl is itself, and is used for it's own code. I want to be able to bind its 'text' property to my observable collection, as in productColumn2. I so far can't seem to set ProductSelectorTextBoxUserControl DataContext to the DataContext used here.
<DataGrid ItemsSource="{Binding Path=ObservableCollectionItems, Mode=OneWay}" AutoGenerateColumns="False" EnableRowVirtualization="True" >
<DataGrid.Columns>
<DataGridTemplateColumn x:Name="productColumn1" SortMemberPath="Product" >
<DataGridTemplateColumn.CellTemplate>
<DataTemplate>
<productSelector:ProductSelectorTextBoxUserControl Text="{Binding Path=Product, Mode=TwoWay, NotifyOnSourceUpdated=True, UpdateSourceTrigger=LostFocus, ValidatesOnExceptions=True}" />
</DataTemplate>
</DataGridTemplateColumn.CellTemplate>
</DataGridTemplateColumn>
<DataGridTextColumn x:Name="productColumn2" Binding="{Binding Path=Product, Mode=TwoWay, NotifyOnSourceUpdated=True}" />
</DataGrid.Columns>
A:
Thanks @SellMeADog for helping me out on this, however this still took me way way to long to figure out. Final line is:
<productSelector:ProductSelectorTextBoxUserControl x:Name="productSelector" Product="{Binding Path=Item.Product, RelativeSource={RelativeSource FindAncestor, AncestorType=DataGridRow, AncestorLevel=1}, Converter={StaticResource productNameToProductConverter}, Mode=TwoWay, NotifyOnSourceUpdated=True, ValidatesOnExceptions=True}" />
Key points are RelativeSource DataGridRow, Path is Item(ObservableCollection).Property
If you notice question referred to text and this refers to product, I had to switch to product and add converter. UserControl would then set its own text
|
[
"graphicdesign.stackexchange",
"0000101924.txt"
] | Q:
How to recreate this text stroke/weight design in Photoshop or Illustrator?
I have been trying to replicate this design without success. I have tried duplicating the object and scaling it up a bit, I also tried using the FX Stroke option.
This is what I want to recreate:
Attempt 1: Duplicating the object and scaling it up a bit
Attempt 2: Using the Stroke option in FX (outline achieved, but font needs a bit of work):
I believe that they are using Varela Round as a typeface.
A:
Do this in Illustrator:
Select your text and convert to outlines via Ctrl+Shift+O
With the resulting object selected, go to 'Object → Path → Offset Path', tick the 'Preview' on and play with the settings here
Hit 'Ok', then do a 'Pathfinder → Unite', then send this to back via Ctrl+Shift+[ and apply a different colour
Then some more manual tweaking might be needed to join some of the points to further simplify the resulting outline
|
[
"stackoverflow",
"0015195109.txt"
] | Q:
I can't call the Intent class inside the thread
I want to show message after redirect the current class to another class.but this code
just display the message, not redirect to another class.I also tried separate Handler class,But not working. pls help to solve the prbm.
but.setOnClickListener(new View.OnClickListener()
{
public void onClick(final View v)
{
new Thread(new Runnable()
{
public void run()
{
try
{
/* sample code */
showToast();
}
catch (IOException e)
{
}
}
}
).start();
}
public void showToast() {
hd.post(new Runnable() {
public void run() {
Intent myIntent = new Intent(v.getContext(), List.class);
startActivity(myIntent);
Toast.makeText(getApplicationContext(),"Redirect to main menu", Toast.LENGTH_SHORT).show();
}
});
}
});
A:
Rule : Do not try UI stuff in threads.
Work Around : You can use AsyncTask in Android to carry on the heavy stuff in background while showing progress dialog in foreground. On end of the background thread's execution, do your UI work.
Read this to know more about the usage of AsynTask : http://developer.android.com/reference/android/os/AsyncTask.html
|
[
"stackoverflow",
"0018374789.txt"
] | Q:
Export To Excel Work while debugging my MVC C#.Net application, but not when I publish and deploy it
I have an C# .Net MVC Application. I have done code for Export to Excel for Exporting data stored in datatable. I have stored the datatable in session until user press export button. When user press on export I fetch data from datatable via Ajax Call and export it. I have also kept a message when data exported successfully.
The problem is its works fine while debugging the application, but when I deploy the application it doesn't works. But it shows success message instead of error message. The other ajax calls in application for fetching data or storing data works fine.
I tried to debug the deployed application; exception occurs at line
Excel.Application excelApp = new Excel.Application();
the exception is
System.UnauthorizedAccessException was caught
Message=Retrieving the COM class factory for component with CLSID {00024500-0000-0000-C000-000000000046} failed due to the following error: 80070005 Access is denied. (Exception from HRESULT: 0x80070005 (E_ACCESSDENIED)).
The Export to Excel function
public static void ExportExcel(this DataTable Tbl, string ExcelFilePath = null)
{
try
{
if (Tbl == null || Tbl.Columns.Count == 0)
//throw new Exception("ExportToExcel: Null or empty input table!\n");
Console.WriteLine("ExportToExcel: Null or empty input table!\n");
// load excel, and create a new workbook
Excel.Application excelApp = new Excel.Application();
excelApp.Workbooks.Add();
// single worksheet
Excel._Worksheet workSheet = excelApp.ActiveSheet;
// column headings
for (int i = 0; i < Tbl.Columns.Count; i++)
{
workSheet.Cells[1, (i + 1)] = Tbl.Columns[i].ColumnName;
workSheet.Cells[1, (i + 1)].Font.Bold = true;
workSheet.Cells[1, (i + 1)].Font.Size = 12;
}
// rows
for (int i = 0; i < Tbl.Rows.Count; i++)
{
// to do: format datetime values before printing
for (int j = 0; j < Tbl.Columns.Count; j++)
{
workSheet.Cells[(i + 2), (j + 1)] = Tbl.Rows[i][j];
}
}
//int k = Tbl.Rows.Count;
// check fielpath
if (ExcelFilePath != null && ExcelFilePath != "")
{
try
{
workSheet.SaveAs(ExcelFilePath);
excelApp.Quit();
//MessageBox.Show("Excel file saved!");
}
catch (Exception ex)
{
//throw new Exception("ExportToExcel: Excel file could not be saved! Check filepath.\n"+ ex.Message);
Console.WriteLine("ExportToExcel: Excel file could not be saved! Check filepath.\n"+ ex.Message);
}
}
else // no filepath is given
{
excelApp.Visible = true;
}
}
catch (Exception ex)
{
//throw new Exception("ExportToExcel: \n" + ex.Message);
Console.WriteLine("ExportToExcel: \n" + ex.Message);
}
}
This is code to call the function
public ActionResult JsonExportToExcel()
{
DataTable table = (DataTable)Session["filterCRMRequestDatatable"];
ExportToExcel.ExportExcel(table, "");
var result = "true";
return Json(result, JsonRequestBehavior.AllowGet);
}
The ajax call code
$("#ExportToExcel").click(function () {
//blur page
$('#loading_div').removeClass("loading-css-back").addClass("loading-css-front");
$('#loading_div').fadeIn();
$('#Full_page_content').removeClass("main-div-front").addClass("main-div-back");
$('#Full_page_content').fadeOut();
$.ajax({
url: '/FilterCRMRequest/JsonExportToExcel/',
type: "POST",
dataType: "json",
success: function (data) {
alert("Data Exported Successfully");
//active the page
$('#loading_div').removeClass("loading-css-front").addClass("loading-css-back");
$('#loading_div').fadeOut();
$('#Full_page_content').removeClass("main-div-back").addClass("main-div-front");
$('#Full_page_content').fadeIn();
},
error: function (xhr, props) {
if (xhr.status == 401) {
alert("Session Expired. Please Login Again");
window.location.href = "/CRMLogin/LogOn";
}
else {
alert("Sorry some Error occured. Please Try again.");
//active the page
$('#loading_div').removeClass("loading-css-front").addClass("loading-css-back");
$('#loading_div').fadeOut();
$('#Full_page_content').removeClass("main-div-back").addClass("main-div-front");
$('#Full_page_content').fadeIn();
}
}
});
});
A:
I don't see you throwing any exception or returning any error code - that might be, why you see the success message still.
The access-denied can be a permission problem. Do you have MS Excel installed on the server where you are deploying the application? - Also I got an Access Denied after switching from Server 2003 to Server 2012 and couldn't resolve the issue anymore. Even I found several places, where you could change permissions for WebSites to access MS-Office applications, none of them helped.
In the end I found several articles, that you shouldn't use Office Interop on the server, because:
It uses the actual Office Application in the end
That makes it slow and resource consuming
It's hard to handle multiple requests at the same time
If the code fails, the application might keep running => it might never work again, until you restart the process
You might want to consider using a .net implementation of apache POI - NPOI. With this library you can manipulate Excel, Word and PowerPoint files.
If you are ok with using the new xml-based Excel Files (xlsx) you can use also directly Microsofts OpenXML SDK or a wrapper around this library - SpreadsheetLight
|
[
"math.stackexchange",
"0003528827.txt"
] | Q:
Is the following generalization of Strong Law of Large Numbers valid?
According to SLLN, if $X_1, X_2, \ldots$ is an infinite sequence of i.i.d. random variables with expected value $\mu$ and $S_n := \sum_{i=1}^n X_i/n$ then
$S_n \to \mu$ almost surely.
If the sequence is instead $X_{1,1}, X_{2,1}, X_{2,2}, \ldots, X_{n,1}, \ldots,X_{n,n}, X_{n+1,1}, \ldots$ whose terms are i.i.d. random variables with expected value $\mu$ and $S_n := \sum_{i=1}^n X_{n,i}/n$, can we still say $S_n \to \mu$ almost surely? If not are there any extra conditions that make this true?
I will give an example for why this is not trivial. Consider distribution of variables is Bernoulli with $p=1/2$ and the sample
$0, 1, 1, 0, 0, 0, 1, \ldots$. That is $(2n-1) \times 0$ are followed by
$2n \times 1$ and that is repeated for every $n > 0$. For this sequence $S_n$ converges to $1/2$ in the first case and the limit does not exist in the second.
If the probability of all such examples is $0$ then convergence will be almost sure, but this is something that can probably be proven on a case by case with union bound inequality. I just wonder whether there is some general result that makes such analysis easier.
A:
First observe that in this setting, the sequence $\left(S_n\right)_{n\geqslant 1}$ is independent. For an independent sequence, in view of the Borel-Cantelli lemma, almost sure convergence and complete convergence are equivalent. Hence $S_n\to \mu$ almost surely if and only if for all positive $\varepsilon$,
$$\tag{*}
\sum_{n\geqslant 1}\mathbb P\left(\lvert S_n-\mu\rvert \gt\varepsilon\right)<+\infty.
$$
Let $(Y_i)_{i\geqslant 1}$ be an i.i.d. sequence such that $Y_1$ has the same law as $X_{1,1}$. Then $(*)$ is equivalent to
$$
\forall \varepsilon>0, \sum_{n\geqslant 1}\mathbb P\left(\left\lvert \sum_{j=1}^n(Y_j-\mu)\right\rvert \gt n\varepsilon\right)<+\infty.
$$
By Theorem 3 in this paper by Baum and Katz, this is equivalent to $\mathbb E[Y_1^2]<\infty$, hence we do need extra conditions.
|
[
"math.stackexchange",
"0001296120.txt"
] | Q:
Can one prove divergence by showing a series has at most one solution for an=0?
Say I have any series, I would think it was enough to show that this series equals 0 at most once to prove it diverges. My logic is,
For a series:
$\sum a_n →∞$, and diverges, if $a_n≠0$ for $n→∞$
$\sum a_n →h∈R$, and converges, if $a_n=0$ for $n→∞$
Therefore if a series converges:
$a_n=0$ for all $n>ϵ$ where ϵ is close to ∞
$n>ϵ$ for x values of n
$x>1$ if $a_n=0$ for n→∞
$\therefore$ If a series $a_n$ has at most one real solution for $a_n=0$ it must diverge
Alternatively, if this is false, is it enough to show it has at most one solution for $a_n=x$ where x is very close to 0, and therefore diverges
It this reasoning correct?
A:
This reasoning is incorrect. The issue is that there are series that converge with terms that are all non-zero.
A classical example is the geometric series. Define $a_n = ( \frac{1}{2} )^n$ for $n \geq 0$. It is clear that there are no solutions to $a_n = 0$, and yet the series converges! (in this case, $\sum a_n = 2$ !)
Moreover, what you have written has some poor intuitions resting behind it. Your opening statements are both incorrect, for example. If for all $n$, $a_n \neq 0$, then we do not get that the series diverges. In fact, we can only say that a partial converse to this statement is correct. It is true that IF a series diverges, then $a_n \neq 0$ for infinitely many $n$. A counterexample to your statement is the sequence $a_n = 1$ if $n$ is even, and $a_n = 0$ if $n$ is odd. Note that $\sum a_n \rightarrow \infty$, yet it also has infinitely many terms that are $0$.
Your second statement is close to correct, but it belies some poor intuitions on how limits work. The correct statement is that IF a series $\sum a_n$ converges, then $\lim_{n \rightarrow \infty}a_n = 0$. This is very different than $a_n =0$ since, as in the geometric series example, a series can converge without any of the terms being $0$ on their own.
As a final thought, it is best not to use the phrase "where $\epsilon$ is close to $\infty$". One immediate question that comes to mind if I see this phrase while grading a homework assignment is "well how close to $\infty$ is $\epsilon$?". The short answer is that since $\infty$ isn't a number, it's not good to think of things being "close" to it in any meaningful way, and in fact, the ONLY way to "approach" infinity is via a limit. So just use the limit notation, trust me, it won't bite.
|
[
"stackoverflow",
"0043306592.txt"
] | Q:
Snap.svg: How to use Set.bind(...)?
I can't figure out how to use the Set.bind(...) feature for Snap.svg.
Below is an example with three(3) elements in a set: 2 circles and an ellipse.
I'd like to access and change some attr's in the various elements, using bind.
A few examples of bind would be appreciated.
(Actually, at this moment, I can't see any advantage in using the Set object, rather than an array. Are there any features of the Set that can't be handled just as well with an array?)
<!DOCTYPE HTML>
<html>
<head>
<script type="text/javascript" src="http://svgDiscovery.com/_SNP/snap.svg-min.js"></script>
</head>
<body>
<svg id=mySVG width=400 height=200></svg>
<script>
var SNPsvg = Snap("#mySVG");
var circle1 = SNPsvg.circle(150,100,50).attr({fill: 'red' });
var circle2 = SNPsvg.circle(250,100,50).attr({fill: 'blue' });
var ellipse = SNPsvg.ellipse(200,100,50,20).attr({fill: 'green' });
var mySet= Snap.set(circle1,circle2,ellipse)
setTimeout(function()
{
//mySet.bind(...)
},1000)
</script>
</body>
</html>
A:
The main reason to use a set, is that you can act on every element with a single command. For example...
mySet.animate({ transform: 's2' },1000)
jsfiddle
Which will then act on every single element with that animation.
Why would you use Set.bind ? I must admit, I've never used it, nor seen the purpose yet, but I assume there is one :).
So to the actual question, how is it used. I guess you do..
mySet.bind('x', circle1, 'cx' )
mySet.attr({ 'x': '200' })
jsfiddle
If you set attribute x, it will set attribute cx on circle1 in this case.
Or
mySet.bind('x', function( val ) { console.log( val, ' is passed' )} )
mySet.attr({ 'x': '200' })
jsfiddle
As to why though, I'm not sure :), I can see the advantage of using a set object, but not particularly with set.bind(), especially as it doesn't seem to pass 'this' to the function. I was wondering if it was something like if you set x on a set of circles and rects, you could adjust cx OR x somehow, but I don't see how that is done in any simple way, if the object that's being acted on isn't passed somehow.
I'd normally be more inclined to do something like...
mySet.forEach( function( el ) { el.attr({ fill: 'blue' }) } );
|
[
"stackoverflow",
"0008108569.txt"
] | Q:
RubyMine - can't find "directory_watcher" gem
I am using RubyMine (for the first time) to work on some existing Ruby code, and first thing I see after loading the project is that there is a warning:
The directory_watcher gem is installed (version 1.4.1) but RubyMine cannot see it.
Is this a known issue, or is there something I need to do to remedy this issue?
A:
You should define gems in the Gemfile, refer to help.
|
[
"stackoverflow",
"0036405283.txt"
] | Q:
Problems with python class inheritance
I'm playing around with python class inheritance, but I can't seem to get the child class working.
The error message that I'm getting here is:
must be a type not classobj
Here is the code:
class User():
"""Creates a user class and stores info"""
def __init__(self, first_name, last_name, age, nickname):
self.name = first_name
self.surname = last_name
self.age = age
self.nickname = nickname
self.login_attempts = 0
def describe_user(self):
print("The users name is " + self.name.title() + " " + self.surname.title() + "!")
print("He is " + str(self.age) + " year's old!")
print("He uses the name " + self.nickname.title() + "!")
def greet_user(self):
print("Hello " + self.nickname.title() + "!")
def increment_login_attempts(self):
self.login_attempts += 1
def reset_login_attempts(self):
self.login_attempts = 0
class Admin(User):
"""This is just a specific user"""
def __init__(self, first_name, last_name, age, nickname):
"""Initialize the atributes of a parent class"""
super(Admin, self).__init__(first_name, last_name, age, nickname)
jack = Admin('Jack', 'Sparrow', 35, 'captain js')
jack.describe_user()
I'm using Python 2.7
A:
The User class must inherit from object if you are going to call super() on it later.
class User(object):
...
Python2 distinguishes between old-style classes that did not inherit from object and new style classes that do. It's best to use new style classes in modern code, and never good to mix them in an inheritance hierarchy.
|
[
"stackoverflow",
"0050291837.txt"
] | Q:
Set element height from another element in Angular2
I have two divs in a section which contains dynamic content. The left container contains a list of numbers and the other one list of input fields. I need to prioritize container of input fields if that container stretches out to 600px of height, I need to have that height on my number container and then that element goes into separate scroll if its longer than 600px.
Example img
Code example
<section>
<div class="numbers">
<div>1</div>
<div>1</div>
<div>1</div>
<div>1</div>
<div>1</div>
<div>1</div>
<div>1</div>
<div>1</div>
<div>1</div>
<div>1</div>
<div>1</div>
<div>1</div>
<div>1</div>
<div>1</div>
</div>
<div class="inputs">
<input type="text">
<input type="text">
<input type="text">
<input type="text">
</div>
</section>
section {
display: flex;
}
.numbers {
margin-right: 50px;
}
.numbers div {
background: black;
height: 20px;
width: 20px;
margin-bottom: 10px;
color: #fff;
}
.inputs {
display: flex;
flex-direction: column;
}
input {
margin-bottom: 20px;
}
A:
This is my solution to this problem, i made a function that is called in Oninit and every button that updates the content and on html i called it [style.height.px]="elHeight - 100"
This is my Typescript code
getHeight() {
const leftEl = document.getElementById('number-col');
const rightEl = document.getElementById('question-col');
setTimeout(() => {
this.elHeight = rightEl.clientHeight;
}, 100);
}
|
[
"datascience.meta.stackexchange",
"0000002523.txt"
] | Q:
Do we have a 'canonical' question for "how to avoid overfitting"?
I've encountered this question looking for "some guideline about how to manage the over-fitting problem". OP has enough specifics in their question for me to give a specific answer, but I tried looking for a canonical answer for this very, very common question, and couldn't find any...
Did I just happen to miss it? Or maybe we don't want a canonical answer to such a broad question (I'd argue we do)?
Or maybe there are plenty of 'static' guides online in towardsdatascience, and we should focus on specific questions?
A:
I don't know of such a canonical question/answer, but I will argue in favor of it.
The canonical question/answer gives us a clear place to point users to when we close a question as a duplicate. This approach is especially useful for questions that are very common for beginners in the area. With the canonical approach, we can curate a single high-quality question that captures the essence of the common issue, and know that we have one or more high-quality answers to it.
Such resources for beginners may exist on other sites, but we as a community cannot be 100% certain those sites will remain active and the content or links unchanged. With a canonical question/answer on this site, we can be certain that it will survive as long as StackExchange does.
Here is a nice meta post from the Chemistry community (my primary field and site) describing their approach to canonical questions and answers. It also lists canonical question/answer pairs that have been developed.
https://chemistry.meta.stackexchange.com/questions/3472/the-giant-list-of-duplicates
I am the author of one canonical answer
https://chemistry.stackexchange.com/questions/98159/how-to-name-binary-inorganic-compounds-given-their-chemical-formula-and-vice
and one canonical question/answer pair.
https://chemistry.stackexchange.com/questions/50684/how-can-i-predict-if-a-reaction-will-occur-between-any-two-or-more-substances
This second question is a chemistry equivalent of a common question novices have. Novices think they are asking what appears to be a simple question, but the true answer amounts to the sum of the knowledge of the field. The overfitting question is similar. The problem is common. Novices may want a quick fix when there are actually a wide range of solutions depending on what you are trying to accomplish.
A:
In general this is one of those very basic questions that I struggle to think a topic more suited for a canonical question in "data science" than this.
However the one problem I see is that any good answer to such questions has two parts:
One general truth about what overfitting is and what general ways there are to combat it regardless of used language, model, domain, problem, etc.
A more specific operative insight into handling an overfitting problem that won't go away by simply using cross-validation, etc. Since data science SE is an applied topic I would expect good answers and questions here to deal with actual coding problems and therefore solutions would include actual code or library recommendations.
Obviously the second part is very hard to put into a canonical question, should we focus on python or R for example, do we recommend a train-test split or cross-validation (depends on the model and problem for me), etc.
In short
I'd argue for general overfitting questions there should be a canonical answer but there will still be a need for more specific overfitting questions and answers.
A:
Since https://datascience.stackexchange.com/ is pretty much a duplicate of https://stats.stackexchange.com/, don't forget to look at https://stats.stackexchange.com/.
E.g., here is a pretty canonical answer on https://stats.stackexchange.com/: What should I do when my neural network doesn't generalize well?. It overlaps a lot with yours. Also see Avoid overfitting in regression: alternatives to regularization and https://stats.stackexchange.com/questions/tagged/overfitting?tab=Votes
So much human time wasted resulting from duplicating https://stats.stackexchange.com/...
|
[
"academia.stackexchange",
"0000154255.txt"
] | Q:
Organized or co-organized?
I organized a couple of workshops, as in I was the correspondent person, and I designed the workshop, invited others to co-organize with me, was the lead editor to proceedings etc. but I feel awkward when I say "I organized" as eventually there was a board of organizers. Should I say "I organized" or "co-organized"? Is there a right way to do this? Is it vain to say I organized? On the other hand, if I am invited to take part in organizing board, I say "I co-organized" and mostly I also indicate in which board, which responsibilities/tasks/roles I have taken on in an attempt to make it clear that I wasn't the lead organizer.
A:
There are other, more specific, possibilities. "I led the organization of ...", or something similar. "I was the lead organizer and editor of...". On the other side, "I aided in the organization of...".
Don't make it a title, but a description, unless the organization requires titles.
|
[
"stackoverflow",
"0003598023.txt"
] | Q:
Render more than one objects in the same JTable cell
I need to display a cell data (20.2,true) in Jtable in which 20.2 is float and true is a boolean value in the format (20.2,[JCheckBox]).Is it possible to render 2 different objects in such a manner?
A:
Yeah it is. But I think you will need a Compound-Renderer, which means you have to create your own CellRenderer implementing TableCellRenderer or extending the existing DefaultTableCellRenderer. At least as long as you just want to display these values in your table, this should work fine for you.
Your Compound will consist of a Label for displaying your float and a checkbox for displaying your boolean.
EDIT:
Ok, here a small example:
/**
* Example for CompoundRenderer
*
* @author ymene
*/
public class CompoundRendererExample extends JPanel
{
public static void main( String[] args )
{
JFrame frame = new JFrame( "Example for rendering JTable - values with CompoundRenderer" );
frame.setDefaultCloseOperation( WindowConstants.EXIT_ON_CLOSE );
frame.add( new CompundRendererExample() );
frame.pack();
frame.setVisible( true );
}
public CompoundRendererExample()
{
JScrollPane scrollPane = new JScrollPane();
JXTable table;
table = new JXTable( new TableModel() );
table.setFillsViewportHeight( true );
for ( int i = 0; i < table.getModel().getColumnCount(); i++ )
table.getColumn( i ).setPreferredWidth( 200 );
scrollPane.setViewportView( table );
add( scrollPane );
//Declaring compound-renderer
table.setDefaultRenderer( FloatBool.class, new FloatBoolRenderer() );
}
}
class TableModel extends AbstractTableModel
{
private String[] columnNames = { "Float-Boolean" };
private Object[][] data = { { new FloatBool( 2.2f, true ) }, { new FloatBool( 3.2f, false ) } };
public int getColumnCount()
{
return columnNames.length;
}
public int getRowCount()
{
return data.length;
}
@Override
public String getColumnName( int col )
{
return columnNames[ col ];
}
public Object getValueAt( int row, int col )
{
return data[ row ][ col ];
}
@Override
public Class getColumnClass( int c )
{
if ( getValueAt( 0, c ) == null )
return Object.class;
return getValueAt( 0, c ).getClass();
}
@Override
public boolean isCellEditable( int row, int col )
{
return true;
}
@Override
public void setValueAt( Object value, int row, int col )
{
data[ row ][ col ] = value;
fireTableCellUpdated( row, col );
}
}
class FloatBoolRenderer extends DefaultTableCellRenderer
{
JLabel floatPartLabel;
JCheckBox booleanPartCheckBox;
JPanel container;
public FloatBoolRenderer()
{
floatPartLabel = new JLabel();
booleanPartCheckBox = new JCheckBox();
container = new JPanel();
container.setLayout( new BorderLayout() );
container.add( floatPartLabel, BorderLayout.CENTER );
container.add( booleanPartCheckBox, BorderLayout.EAST );
container.setVisible( true );
}
@Override
public Component getTableCellRendererComponent( JTable table, Object value, boolean isSelected,
boolean hasFocus, int row, int column )
{
if ( value != null )
{
super.getTableCellRendererComponent( table, value, isSelected, hasFocus, row, column );
if ( value instanceof FloatBool )
{
FloatBool floatboolean = (FloatBool) value;
booleanPartCheckBox.setSelected( floatboolean.getBooleanValue() );
floatPartLabel.setText( "" + floatboolean.getFloatValue() );
}
}
return container;
}
}
class FloatBool
{
float floatValue;
boolean booleanValue;
public FloatBool( float floatValue, boolean booleanValue )
{
this.floatValue = floatValue;
this.booleanValue = booleanValue;
}
public boolean getBooleanValue()
{
return booleanValue;
}
public float getFloatValue()
{
return floatValue;
}
}
Not perfect yet, but should give you ideas how to design your own renderer.
|
[
"stackoverflow",
"0010681766.txt"
] | Q:
Emacs org-mode: textual reference to a file:line
I am using org-mode in Emacs to document my development activities. One of the tasks which I must continuously do by hand is to describe areas of code. Emacs has a very nice Bookmark List: create a bookmark with CTRL-x r m, list them with CTRL-x r l. This is very useful, but is not quite what I need.
Org-mode has the concept of link, and the command org-store-link will record a link to the current position in any file, which can be pasted to the org-file. The problem with this is two-fold:
It is stored as an org-link, and the linked position is not directly visible (just the description).
It is stored in the format file/search, which is not what I want.
I need to have the bookmark in textual form, so that I can copy paste it into org-mode, end edit it if needed, with a simple format like this:
absolute-file-path:line
And this must be obtained from the current point position. The workflow would be as simple as:
Go to the position which I want to record
Call a function: position-to-kill-ring (I would bind this to a keyboard shortcut)
Go to the org-mode buffer.
Yank the position.
Edit if needed (sometimes I need to change absolute paths by relative paths, since my code is in a different location in different machines)
Unfortunately my lisp is non-existent, so I do not know how to do this. Is there a simple solution to my problem?
A:
(defun position-to-kill-ring ()
"Copy to the kill ring a string in the format \"file-name:line-number\"
for the current buffer's file name, and the line number at point."
(interactive)
(kill-new
(format "%s:%d" (buffer-file-name) (save-restriction
(widen) (line-number-at-pos)))))
A:
You want to use the org-create-file-search-functions and org-execute-file-search-functions hooks.
For example, if you need the search you describe for text-mode files, use this:
(add-hook 'org-create-file-search-functions
'(lambda ()
(when (eq major-mode 'text-mode)
(number-to-string (line-number-at-pos)))))
(add-hook 'org-execute-file-search-functions
'(lambda (search-string)
(when (eq major-mode 'text-mode)
(goto-line (string-to-number search-string)))))
Then M-x org-store-link RET will do the right thing (store a line number as the search string) and C-c C-o (i.e. M-x org-open-at-point RET) will open the file and go to this line number.
You can of course check for other modes and/or conditions.
|
[
"stackoverflow",
"0018575400.txt"
] | Q:
is it possible to retrieve Facebook user name or id from photo URL
If i have facebook users photo's URL, for example: https://fbcdn-sphotos-e-a.akamaihd.net/hphotos-ak-ash3/885089_523687507674066_732194510_o.png
Can i retrieve user's name or id which own this photo?
A:
First, fetch the photo_id from the url. For eg:
Link: https://fbcdn-sphotos-e-a.akamaihd.net/hphotos-ak-ash3/885089_523687507674066_732194510_o.png
PhotoId: 523687507674066
Then make the \GET request to this ID. Just like this:
\GET http://graph.facebook.com/523687507674066
(you can validate this link in the browser)
You'll get the JSON response just like-
....
from: {
category: "Recreation/sports website",
name: "Emocje do pełna",
id: "290868840955935"
},
....
So, you just have to fetch the id from the from paramter
A:
Yep https://www.facebook.com/photo.php?fbid=523687507674066 The middle number is the photo id
|
[
"stackoverflow",
"0002544024.txt"
] | Q:
How can we handle concurrency errors in LINQ to SQL?
How can we handle concurrency errors in LINQ to SQL?
A:
One way is by setting the modes on each column for how it participates in conflict checking. There are three options: Always, Never & WhenChanged
For more info, check here and here
Also an option is using the ConflictMode parameter to SubmitChanges (one of ConflictMode.ContinueOnConflict or ConflictMode.FailOnFirstConflict. If you set it to the former, the commit will throw when complete, but you will have a collection of failed submissions for further processing... see this answer for more info.
|
[
"stackoverflow",
"0000299334.txt"
] | Q:
parse meta tags in Java
I have a collection of HTML documents for which I need to parse the contents of the <meta> tags in the <head> section. These are the only HTML tags whose values I'm interested in, i.e. I don't need to parse anything in the <body> section.
I've attempted to parse these values using the XPath support provided by JDom. However, this isn't working out too well because a lot of the HTML in the <body> section is not valid XML.
Does anyone have any suggestions for how I might go about parsing these tag values in manner that can deal with malformed HTML?
Cheers,
Don
A:
You can likely use the Jericho HTML Parser. In particular, have a look at this to see how you can go about finding specific tags.
|
[
"physics.stackexchange",
"0000212112.txt"
] | Q:
Will the Sun ever get 100x powerful? If so, when?
I was doing a theoretical research regarding life on Titan. The temperature of Titan is so low, and it needed more sunlight, as a result, the Sun would require to get hotter. My question is, when will the Sun emit 100 times more power than as that of today?
I referred to
(source)
and Stefan-Boltzmann law,
$$P= A\varepsilon \sigma T^4,$$
but could not figure out. It may be even impossible that the sun never reaches this stage. I would gladly appreciate any logics, mathematics, or even opinions too.
A:
This is the plot you are looking for. This a solar model taken from the Padova evolutionary tracks by Bertelli et al. (2008). It shows the (log) solar luminosity in terms of the current solar luminosity, as a function of age in years.
From this plot we see that the Sun reaches 100 times its present luminosity at an age of 12.50 Gyr (that is 12.50-4.57=7.43 billion years from now). The Sun is on the first ascent giant branch, burning hydrogen in a shell around its inert helium core.
In practice the figure is not precise to 3 sig figs because it depends to a certain extent on the details of the mass-loss during the giant branch phase and also perhaps more importantly on mixing near the Sun's core, which is still not fully understood.
A:
If this site is to be believed, it will only happen for a relatively brief period during the Sun's red giant phase, 7.5 billion years from now (give or take):
Around the year 7.1 billion AD, the Sun will begin evolving so rapidly that it will cease to be a main-sequence star. Its position on the H-R diagram will begin to shift from where it is now, near the center, towards the upper right where the red giants live. This is because the Sun's helium core will eventually reach a critical point where the pressure from normal gasses cannot hold up the crushing weight being piled on it (not even gasses heated to tens of millions of degrees). A tiny seed of electron-degenerate matter will begin to grow at the center of the Sun. The details of this transition are subject to debate, but theoretical calculations indicate that it will begin when the Sun's inert helium core reaches about 13% of a solar mass, or about 140 Jupiters.
At this point in its life, the Sun will become unruly. ... 500 million years after it hits the critical point, the Sun's luminosity will balloon to 34 $L_0$, fiery enough to create glowing lakes of molten aluminum and copper on the Earth's surface. In only 45 million years more it will reach 105 $L_0$, and 40 million years after that it will leap to an incredible 2,300 $L_0$.
$L_0$ here is the sun's current luminosity (i.e., its total luminous power output). It sounds like the period of time when the Sun's luminosity is between 10 & 1000 times what it is now will only last 100 million years at most. Unfortunately, this would probably not be long enough for Titanean life to evolve into anything interesting (more's the pity.)
Oh, and the dip in the "temperature" graph you posted in the OP is the beginning of the red giant phase. Note that the surface temperature of the Sun is actually cooler during the period in question; but the huge radius of the Sun at this time gives it a much larger surface area $A$ which more than makes up for it.
|
[
"stackoverflow",
"0025099601.txt"
] | Q:
Horner's algorithm in SML?
I am trying to implement Horner's algorithm in SML.
fun horner(lst1:real list,x:real) =
let
val i = ref 1
val result = ref (List.last(lst1))
in
if (lst1) = ([]:real list) then 0.0
else
while (!i <= length(lst1)-1) do
(result:=!result*x+List.nth(lst1,length(lst1)-(!i)-1);
i := !i+1);
!result
end;
Takes on a{n}, the coeff of x^n, as its initial result, then using horner's evaluates a polynomial.
Evaluates as ((a{n}*x+a{n-1})*x+a{n-2})..The list contains the coefficients of the polynomial.
Problem is the "if lst1 = []....else" part.
Employing only the while loop makes the program run well.
But I can't think of anything that is wrong with that part.
A:
You've tried to write some very imperative-looking code, and frankly, it's a bit of a mess. If you try to write your SML code as if it was Java, well, that's gonna hurt.
Instead of trying to fix your original code, let's redo it in a more functional style. First of all, pattern matching. In your code, you use an if-then-else expression to check if your list is empty. Instead, we'll use pattern matching:
fun horner ([] , x) = 0.0
| horner (n::ns, x) = ...
This has two benefits. First, it splits the list up for us - we can now use n to refer to the first item in the list, and ns to refer to the rest. Second, it's way more readable.
Now we need the actual math. Now, horner's method uses a variable, which you've called result in your code, to accumulate the answer. However, we're coding in a mostly functional language, and avoiding refs would be nice. Instead, we'll add an extra parameter to the function.
fun horner ([] , x, acc) = acc
| horner (n::ns, x, acc) = ...
Of course, we want the function to be usable with only two parameters, so we put the math in a helper function, and make the real function call the helper function:
fun horner' ([] , x, acc) = acc
| horner' (n::ns, x, acc) = ...
fun horner (xs, x) = horner' (xs, x, 0.0)
This is a fairly common pattern to see in functional programming, and SML has tools to hide the helper function so we don't clutter up the global namespace. For example, we could put the helper function inside a let-expression:
fun horner (xs, x) = let
fun horner' ([] , x, acc) = acc
| horner' (n::ns, x, acc) = ...
in
horner' (xs, x, 0.0)
end
Finally, we add the recursive call of horner'.
fun horner (xs, x) = let
fun horner' ([] , x, acc) = acc
| horner' (n::ns, x, acc) = horner' (ns, x, n + x * acc)
in
horner' (xs, x, 0.0)
end
And here's an of what happens when we call the horner function:
horner ([3.0, 2.0, 4.0], 2.0) ~> horner' ([3.0, 2.0, 4.0], 2.0, 0.0)
~> horner' ([2.0, 4.0] , 2.0, 3.0 + 2.0 * 0.0)
~> horner' ([2.0, 4.0] , 2.0, 3.0)
~> horner' ([4.0] , 2.0, 2.0 + 2.0 * 3.0)
~> horner' ([4.0] , 2.0, 8.0)
~> horner' ([] , 2.0, 4.0 + 2.0 * 8.0)
~> horner' ([] , 2.0, 20.0)
~> 20.0
|
[
"salesforce.stackexchange",
"0000022043.txt"
] | Q:
Solutions for using https on custom domains on a force.com site
We have a force.com site which has a simple lead form. We want to use a custom domain name like https://www.companyname.com/leadform as our url which we can use for marketing. I know we can register a custom domain and point the cname record to the force.com site url. But is it possible for me to have a ssl certification on companyname.com point to salesforce site page? Has any body come up with a solution for secure pages using custom domain like https://www.companyname.com/leadform as an example?
Buyan
A:
To the contrary of the linked documentation from @crmprogdev, as of at least August 2013 Salesforce does support this scenario.
SFDC Help: Adding a Domain
To associate certificates with a domain: Contact salesforce.com
A couple of key points:
You must use a CA-Signed certificate
You must use a CSR generated by
Salesforce
The certificate must be 2048 bits in length
Answers to the questions below
How do I associate our domain which www.companyname.com managed by our infrastructure team to salesforce domain?
This is done using your DNS A or CNAME records. Salesforce can provide direction on how the DNS records should be configured.
Are you telling me that if we have a CA signed certificate for our domain, we can easily upload this to salesforce and have force.com site pages display with a custom SSL url like https:///www.mycompany.com/contact as an example?
A URL like this one: https:///www.mycompany.com/contact could be handled with the Site.UrlRewriter interface but if you don't want to implement a UrlRewriter, your page URLs will take on the normal VF path of https:///www.mycompany.com/apex/contact (where you have a VF page named contact).
Salesforce provides tools for managing certificates within your org. You would use these tools to generate a Certificate Signing Request (CSR) and have that request signed by the CA and then you can upload the certificate into your org.
Can you please explain how this would help to display custom domains with https on force.com sites please?
Per that help document, you can contact Salesforce and they can associate your force.com site with the SSL certificate which you uploaded. After that is complete, your force.com site will be available using your SSL certificate via your custom web address defined on your site.
A:
EDIT
The answer to this question has changed with the SU14 release. See Configure a Custom Domain for Your Community which provides instructions that primarily involve contacting SF Support and the caveats highlighted below.
To enable HTTPS custom domains for your organization: contact salesforce.com.
To associate certificates with a domain: contact salesforce.com.
From Setup, click Domain Management | Custom URLs. Before you switch the CNAME of your domain name to point to a new target name, ensure that the new target name exists in the DNS by using dig or nslookup. When you created your domain names affects the target of your CNAME:
Domain names that were added before Summer ‘13, typically need to have their CNAME adjusted to point to the fully qualified domain
followed by .live.siteforce.com instead of to the organization’s
force.com sub-domain. For example, if your pre-Summer ‘13 domain is
www.example.com, then the target of its CNAME will need to be
www.example.com.live.siteforce.com instead of example.force.com before
HTTPS will work.
Domain names that were added in or before Summer ‘13, don’t have the 18-character organization ID in the CNAME target.
Domain names that were added in or after Summer ‘13, already point to the proper place for setting up HTTPS in a custom domain.
Domain names that were added in or after Winter ‘14, use a CNAME that points to the fully qualified domain followed by your
organization’s 18-character ID and .live.siteforce.com. For example,
if your domain name is www.example.com and your 18-character
organization ID is 00dxx0000001ggxeay, then the target of its CNAME
will need to be www.example.com.00dxx0000001ggxeay.live.siteforce.com.
Original Answer
Bunyan, take a look at the Sites FAQ which says the following:
Q: Does it support HTTPS custom URLs (not force.com URLs) with our own certificate?
A: Not at this time
and
Q: Can i specify my own SSL certificate if i use a CNAME to brand my URL
A: SSL certificates specify an IP address and at the current time we do not provide a feature to host SSL certificates for sites other than the default domain force.com.
From the above, unless something has changed, I'd conclude that at this time it's not possible to do what you desire.
A:
Private SSL certs don't work. We've been on the road once - did everything as instructed by document: get CSR from SF, cert signed by a CA, uploaded the cert. In the end, it didn't do a thing for the site intended (with the cert URL configured as primary btw and CNAME rediret set up). After a 3 1/2 months case, SF finally said, "nope, feature wouldn't be production available until at least Winter '14". The exact quote from the case owenr was
I just had word with the PM for this feature. They mentioned that the this pilot feature is in hold. They are shooting for the Winter release (safe harbor) to go on a GA ( generally available feature). When this feature becomes public your org will be able to hold the valid SSL certificates for the sites.
Now Spring '14 is almost out, and the feature is still nowhere to be found.
|
[
"stackoverflow",
"0003850775.txt"
] | Q:
UIKeyboardTypeDecimalPad localization
I noticed that UIKeyboardTypeDecimalPad was added in iOS 4.1, and started using it. During the course of my testing, I switched both the language and region to French in the International section of Settings. I expected the decimal key on the keypad in my app to change from a "." to a "," but it didn't.
All I'm doing is this:
_textFieldUnitCost.keyboardType = UIKeyboardTypeDecimalPad;
Any ideas?
A:
As of 4.2.1 the decimal key on the keypad now changes from a "." to "," when switching to a language/region that uses a ","
|
[
"stackoverflow",
"0060625427.txt"
] | Q:
How to get select rows that have first occurrences before column value changes in MYSQL8
I have a MYSQL8 table with Event_TimeStamp and FinalStateand it looks like this
+---------------------------+---------------+
|"Event_TimeStamp" |"FinalState" |
+---------------------------+---------------+
|"2020-03-09 04:57:45.729" |"Available" |
|"2020-03-09 05:14:59.659" |"Available" |
|"2020-03-09 05:27:56.341" |"Available" |
|"2020-03-09 05:41:01.554" |"Available" |
|"2020-03-09 05:58:07.803" |"Available" |
|"2020-03-09 06:06:09.745" |"Available" |
|"2020-03-09 06:18:07.663" |"Available" |
|"2020-03-09 06:26:24.273" |"Available" |
|"2020-03-09 09:29:53.165" |"Offline" |
|"2020-03-09 10:28:00.514" |"Available" |
|"2020-03-09 12:47:54.130" |"Available" |
|"2020-03-09 13:01:30.117" |"Available" |
|"2020-03-09 13:01:59.774" |"Offline" |
|"2020-03-09 13:19:15.772" |"Available" |
|"2020-03-09 14:19:51.521" |"Available" |
|"2020-03-09 14:50:16.872" |"Offline" |
+---------------------------+---------------+
I have to extract rows from the above such that it will have the rows with first "Available" and "Offline", so the output would look like this
+---------------------------+---------------+
|"Event_TimeStamp" |"FinalState" |
+---------------------------+---------------+
|"2020-03-09 04:57:45.729" |"Available" |
|"2020-03-09 09:29:53.165" |"Offline" |
|"2020-03-09 10:28:00.514" |"Available" |
|"2020-03-09 13:01:59.774" |"Offline" |
|"2020-03-09 13:19:15.772" |"Available" |
|"2020-03-09 14:50:16.872" |"Offline" |
+---------------------------+---------------+
I tried a few ways with GROUP BY but I get only the first entries for each of the FinalState and not the rest of them.
Is there a way to get this done with an QUERY or should I write it out in PHP?
A:
You can use lag() and lead() to exhibit records whose final_state is different that in the previous or next row:
select
event_timestamp,
final_state
from (
select
t.*,
lag(final_state) over(order by event_timestamp) lag_final_state,
lead(final_state) over(order by event_timestamp) lead_final_state
from mytable t
) t
where final_state <> lag_final_state or final_state <> lead_final_state
|
[
"stackoverflow",
"0020888206.txt"
] | Q:
Is it necessary to check if a handler exists in a delegate chain before removing it?
I have a small snippet of a delegate-based messaging system, you could Subscribe and Unsubscribe event handlers, and Raise new events.
In my Unsubscribe method, I check to make sure that the handler exist first, before removing it.
My question is: is this check necessary? i.e. can't I just do:
dic[type] -= handler;
without:
if (handler exists)
dic[type] -= handler;
if so, why? - I tried both checking and not checking, they both yield the same practical results. Not sure if there's any reasons why I'd prefer to use either.
Code:
public abstract class GameEvent { }
private static class EventManagerInternal<T> where T : GameEvent
{
private static Dictionary<Type, Action<T>> dic = new Dictionary<Type, Action<T>>();
public static void Subscribe(Action<T> handler)
{
Type type = typeof(T);
if (!dic.ContainsKey(type)) {
dic[type] = handler;
Console.WriteLine("Registered new type: " + type);
}
else {
// make sure the handler doesn't exist first
bool hasHandlerSubscribed = dic[type].GetInvocationList().Any(h => h.Equals(handler));
if (hasHandlerSubscribed) {
Console.WriteLine(handler.Method.Name + " has already subbed to an event of type " + type);
return;
}
dic[type] += handler;
}
Console.WriteLine("Method " + handler.Method.Name + " has subbed to receive notifications from " + type);
}
public static void Unsubscribe(Action<T> handler)
{
Type type = typeof(T);
// make sure the type exists
if (!dic.ContainsKey(type)) {
Console.WriteLine("Type " + type + " hasn't registered at all, it doesn't have any subscribers... at least not in my book...");
return;
}
// get the methods that the delegate points to
// to see if the handler exists or not
bool exist = dic[type].GetInvocationList().Any(h => h.Equals(handler));
if (!exist) {
Console.WriteLine("Method " + handler.Method.Name + " hasn't registered at all, for notifications from " + type);
return;
}
// remove the handler from the chain
dic[type] -= handler;
Console.WriteLine("handler " + handler.Method.Name + " has been removed. it won't take any notifications from " + type);
// if there's no more subscribers to the "type" entry, remove it
if (dic[type] == null) {
dic.Remove(type);
Console.WriteLine("No more subscribers to " + type);
}
}
public static void Raise(T e)
{
Action<T> handler;
if (dic.TryGetValue(e.GetType(), out handler)) {
handler.Invoke(e);
}
}
}
Example Usage: (via a wrapper - I just thought that Class.DoSomething<T> is nicer than Class<T>DoSomething - There is a good reason why I had to go for this setup :) Not the point here though...)
Player p = new Player();
EventManager.Subscribe<OnRename>(OnRenameHandler);
EventManager.Subscribe<OnRename>(AnotherOnRenameHandler);
EventManager.Raise(new OnRename());
EventManager.Unsubscribe<OnRename>(OnRenameHandler);
etc
A:
My question is: is this check necessary?
No, it is not.
why?
That's easy, the check is done by the operator that you're using. It was specifically designed to do nothing if the handler to be removed doesn't exist, rather than, say, throw an exception.
|
[
"meta.stackoverflow",
"0000378263.txt"
] | Q:
Someone was abusing me in comments and now downvoted me with 86 points
Well, it takes a hell of a lot of efforts to give a right answer and it takes even more thought processes to give a suitable explanation of what and how you made the answer.
I woke up this morning and saw a few questions and wrote the answers to them. One got accepted and one was wrong so I deleted it. On seeing this, a user named "Dad" started abusing me in comments in Hindi, and I flagged it.
I went to take breakfast and saw that all my answers and questions were downvoted, like 86 points I have lost from the downvotes.
The user dad was not with 100 points so he might not had done this, but he was surely pissed on me so his alts (alternate accounts), which may be above 100 points, have done this.
I request moderators and system administrators to kindly rectify my points. It really feels painful.
My Stack Overflow profile: https://stackoverflow.com/users/4964136/vir
A:
Your suspicions were right: that was indeed an alt account. We've deleted that alt account and suspended the culprit. There really isn't much of a point waiting out the voting reversal script before raising a flag in situations like this since it's pretty unlikely that the abusive comments and the serial downvotes were not connected.
|
[
"stackoverflow",
"0051862353.txt"
] | Q:
Change my array so values are stored together
I have multiple possible users that are posted from a form to my PHP script through AJAX.
In that script I have the following code:
parse_str($_POST['users'], $useroutput);
foreach($useroutput as $key => $user){
// If both fields are filled in:
if(!empty($user['username']) OR !empty($user['password'])){
$userstring .= $user['username'].' '.$user['password'].'<br>';
}else{
echo 'Empty';
}
}
However the above loop always shows me 'Empty'.
While this is what my array looks like if I print it:
[username] => Array
(
[0] => username
[1] => anotherusername
)
[password] => Array
(
[0] => password
[1] => anotherpassword
)
)
How can I change my array to look like this?:
Array(
[0] => Array
(
[username] = myusername
[password] = mypassword
)
[1] => Array
(
[username] = anotherusername
[password] = anotherpassword
)
)
I've tried different ways of posting the data but until now nothing gives me the array as I need it.
This is how I post my form data to my PHP script:
// Add/edit users script
$( "#companywrap" ).on("click", "#saveuser", function( event ) {
// Stop normal form behaviour
event.preventDefault();
var $form = $("#userform"),
postBody = $form.serialize(),
url = $form.attr( "action" );
var posting = $.post( url, {users: postBody});
// Show result in a div
posting.done(function( data ) {
$( ".resultmessageuser" ).empty().slideDown('fast').append( data );
});
});
My form markup as requested:
<form id="userform" action="includes/userscript.php" method="post" enctype="multipart/form-data">
<div class="card m-b-20">
<div class="card-body">
<div class="form-group fieldGroup">
<div class="form-group row">
<label for="example-text-input" class="col-sm-4 col-form-label">Gebruikersnaam</label>
<div class="col-sm-8">
<input class="form-control" name="username[]" value="<?PHP echo $getcompany['username']; ?>" type="text" required>
</div>
</div>
<div class="form-group row">
<label for="example-text-input" class="col-sm-4 col-form-label">Wachtwoord</label>
<div class="col-sm-8">
<input class="form-control" name="password[]" placeholder="<?PHP echo $editpass; ?>" value='' type="text" required>
</div>
</div>
<div class="input-group-addon">
<a href="javascript:void(0)" class="btn btn-success addMore"><span class="glyphicon glyphicon glyphicon-plus" aria-hidden="true"></span> Extra gebruiker</a>
</div>
</div>
<!-- copy of input fields group -->
<div class="form-group fieldGroupCopy" style="display: none;">
<div class="form-group row">
<label for="example-text-input" class="col-sm-4 col-form-label">Gebruikersnaam</label>
<div class="col-sm-8">
<input class="form-control" name="username[]" value="" type="text" id="example-text-input">
</div>
</div>
<div class="form-group row">
<label for="example-text-input" class="col-sm-4 col-form-label">Wachtwoord</label>
<div class="col-sm-8">
<input class="form-control" name="password[]" placeholder="<?PHP echo $editpass; ?>" value='' type="text" id="example-text-input">
</div>
</div>
<div class="input-group-addon">
<a href="javascript:void(0)" class="btn btn-danger remove"><span class="glyphicon glyphicon glyphicon-remove" aria-hidden="true"></span> Verwijder velden</a>
</div>
</div>
</div>
</div>
</form>
A:
I think you should start by modifying how your HTML is rendered. Currently your form is rendered in this manner:
<form>
<input type="text" name="username[]">
<input type="text" name="password[]">
<input type="text" name="username[]">
<input type="text" name="password[]">
<button type="submit">Submit</button>
</form>
When this is sent to PHP, the POST request would be read like this:
[
"username" => [
0 => "john"
1 => "jane"
]
"password" => [
0 => "pw1"
1 => "pw2"
]
]
However, if you change your HTML to be formatted like this:
<form>
<input type="text" name="credentials[0][username]">
<input type="text" name="credentials[0][password]">
<input type="text" name="credentials[1][password]">
<input type="text" name="credentials[1][password]">
<button type="submit">Submit</button>
</form>
then PHP, will see the POST request like this:
[
"credentials" => [
0 => [
"username" => "john"
"password" => "pw1"
]
1 => [
"username" => "jane"
"password" => "pw2"
]
]
]
Once your HTML is fixed, you would just need to make minor adjustments:
Change $.post( url, {users: postBody});, to $.post( url, postBody);
Now you can use the PHP iteration you initially wanted, like so:
foreach($_POST['credentials'] as $credential){
if(!empty($credential['username']) || !empty($credential['password'])){
$userstring .= $credential['username'].' '.$credential['password'].'<br>';
}else{
echo 'Empty';
}
}
A:
You are looping it incorrectly.
When you loop foreach($useroutput as $key => $user){
You get the following:
(
[0] => username
[1] => anotherusername
)
And at this point you don't have any $user['username'] you have $user[0] and [1]
If you do like this:
foreach($useroutput['username'] as $key => $val){
$users[] = array_combine(['username','password'],array_column($useroutput, $key));
}
Var_dump($users);
Your $users array will work in the array and will have the users grouped as you expect.
|
[
"math.stackexchange",
"0000240462.txt"
] | Q:
$\mathbb{Z}_5 [x]/\langle x^2-2\rangle$ and $\mathbb{Z}_5 [x]/\langle x^2-3\rangle$
Show that $\mathbb{Z}_5 [x]/\langle x^2-2\rangle $ and $\mathbb{Z}_5 [x]/\langle x^2-3\rangle$ are not isomorphic
A:
In addition to the comments, it is also quite easy to build an explicit isomorphism between these two rings. Indeed, define ring homomorphisms $f \colon \mathbb{Z}[x]/\langle x^2-2\rangle$ and $g \colon \mathbb{Z}[x]/\langle x^2-3\rangle$ by the conditions:
$$
\begin{array}{rcl}
f\left([x]_{\langle x^2-2\rangle}\right) &=& [2x]_{\langle x^2-3\rangle}, \\
g\left([x]_{\langle x^2-3\rangle}\right) &=& [3x]_{\langle x^2-2\rangle}.
\end{array}
$$
By $[p(x)]_{\langle q(x) \rangle}$ I denoted the class of $p(x)$ modulo $q(x)$. Of course, the fact that these conditions do define two ring homomorphisms needs checking, which I will omit.
It is quite easy to see that $f\circ g$ and $g \circ f$ are identity maps, so $f$ is an isomorphism.
A:
To simplify a bit the verifications needed in the isomorphism as constructed in the answer by Dan Shved, you could proceed as follows. Let $\alpha\in\Bbb Z_5[x]/\langle x^2-2\rangle$ and $\beta\in\Bbb Z_5[x]/\langle x^2-3\rangle$ be the respective images of $x$. You can think of $\alpha$ as $\sqrt2$ and of $\beta$ as $\sqrt3=\sqrt{-2}$. Neither $2$ nor $3$ has a square root in $\Bbb Z_5$ which shows that the quotients here are both fields; indeed both quadratic extensions of the finite field $\Bbb Z_5$, which is enough to know the are abstractly isomorphic. Since $\Bbb Z_5$ does contain squares root of $-1$ (or $4$), namely $2$ and $3$, you can easily locate the square roots of $2=(-1)\times(-2)$ in the extension $\Bbb Z_5[x]/\langle x^2-3\rangle$: they are $2\beta$ and $3\beta$.
Now consider the ring morphism $f:\Bbb Z_5[x]\to\Bbb Z_5[x]/\langle x^2-3\rangle$ that sends $x$ to $2\beta$; it is obviously surjective. Its kernel contains $x^2-2$ (because $(2\beta)^2=2$), and no polynomials of degree${}<2$ (since $1$ and $2\beta$ are linearly independent over $\Bbb Z_5$), so the kernel is precisely the ideal $\langle x^2-2\rangle$; then by the first isomorphism theorem $f$ induces an isomorphism
$$
\overline f:\Bbb Z_5[x]/\langle x^2-2\rangle\to
\Bbb Z_5[x]/\langle x^2-3\rangle.
$$
One has $\overline f(\alpha)=2\beta$ (and also $\overline f(3\alpha)=\beta$), so $\overline f$ is just the isomorphism of the other answer.
|
[
"stackoverflow",
"0025708734.txt"
] | Q:
swing JTable with ScrollBar - color of square between headers and track
I have a JTable with BasicScrollBarUI, I set the headers background color: table.getTableHeader().setBackground(GuiConstants.backgroundColor);
and the scrolbar background color:
public class ScrollBarUI extends BasicScrollBarUI {
@Override
protected void paintTrack(Graphics g, JComponent c, Rectangle trackBounds) {
c.setBackground(GuiConstants.backgroundColor);
}
}
I still have a square between them that its color won't change.
does anybody knows how to change it also to their color?
thanks
A:
As shown in How to Use Scroll Panes: Providing Custom Decorations, you can use the scroll pane's setCorner() method to add a colored Component:
JPanel panel = new JPanel();
panel.setBackground(Color.gray);
scrollPane.setCorner(JScrollPane.UPPER_RIGHT_CORNER, panel);
You may have to set the panel's opacity to true, and you may want to select a suitable color from the the current Look & Feel using the UIMnager.
|
Subsets and Splits