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3,687,715 | 2010-09-10T19:29:00.000 | 0 | 0 | 1 | 0 | 0 | python,information-retrieval,inverted-index | 0 | 3,688,556 | 0 | 6 | 0 | false | 0 | 0 | You could store the repr() of the dictionary and use that to re-create it. | 2 | 5 | 1 | 0 | I am working on a project on Info Retrieval.
I have made a Full Inverted Index using Hadoop/Python.
Hadoop outputs the index as (word,documentlist) pairs which are written on the file.
For a quick access, I have created a dictionary(hashtable) using the above file.
My question is, how do I store such an index on disk that also has quick access time.
At present I am storing the dictionary using python pickle module and loading from it
but it brings the whole of index into memory at once (or does it?).
Please suggest an efficient way of storing and searching through the index.
My dictionary structure is as follows (using nested dictionaries)
{word : {doc1:[locations], doc2:[locations], ....}}
so that I can get the documents containing a word by
dictionary[word].keys() ... and so on. | Storing an inverted index | 0 | 0 | 1 | 0 | 0 | 3,666 |
3,687,715 | 2010-09-10T19:29:00.000 | 0 | 0 | 1 | 0 | 0 | python,information-retrieval,inverted-index | 0 | 5,341,353 | 0 | 6 | 0 | false | 0 | 0 | I am using anydmb for that purpose. Anydbm provides the same dictionary-like interface, except it allow only strings as keys and values. But this is not a constraint since you can use cPickle's loads/dumps to store more complex structures in the index. | 2 | 5 | 1 | 0 | I am working on a project on Info Retrieval.
I have made a Full Inverted Index using Hadoop/Python.
Hadoop outputs the index as (word,documentlist) pairs which are written on the file.
For a quick access, I have created a dictionary(hashtable) using the above file.
My question is, how do I store such an index on disk that also has quick access time.
At present I am storing the dictionary using python pickle module and loading from it
but it brings the whole of index into memory at once (or does it?).
Please suggest an efficient way of storing and searching through the index.
My dictionary structure is as follows (using nested dictionaries)
{word : {doc1:[locations], doc2:[locations], ....}}
so that I can get the documents containing a word by
dictionary[word].keys() ... and so on. | Storing an inverted index | 0 | 0 | 1 | 0 | 0 | 3,666 |
3,689,766 | 2010-09-11T04:11:00.000 | 1 | 1 | 0 | 0 | 0 | python,nginx,pylons,production-environment,paste | 0 | 3,711,301 | 0 | 1 | 0 | false | 1 | 0 | Your app will be the bottleneck in performance not Apache or Paste.
Nginx is used in lots of production servers so that bit will be fine. I don't know about mod_wsgi but uWSGI is used in production environments and plays well with both nginx and Paste applications.
I currently run a server using Apache + Paste using Apache to serve static content and Paste to handle Pylons. When I stress tested the setup (using default settings on Apache) I got a lot of variation in the time it took to handle requests (varying from 0.5 to 10 secs).
As a test I setup Nginx + uWSGI. Nginx is known to be very good for handling static content and I saw a 10x improvement in the number of files it could serve. The average response time for the Pylons app didn't change (it's DB bound) but the variability dropped to almost zero.
Neither setup dropped a connection or failed to respond so based on this I'll be moving to Nginx + uWSGI for our next app, especially as it has a lot more static content. | 1 | 2 | 0 | 0 | I've developed a website in Pylons (Python web framework) and have it running, on my production server, under Apache + mod_wsgi.
I've been hearing a lot of good things about nginx recently and wanted to give it a try. Currently, it's running as a forwarding proxy to create a front end to Paste. It seems to be running pretty damn fast... Though, I could probably contribute that to me being the only one accessing it.
What I want to know is, how will Paste hold up under a heavy load? Am I better off going with nginx + mod_wsgi ? | Will nginx+paste hold up in a production environment? | 0 | 0.197375 | 1 | 0 | 0 | 693 |
3,694,031 | 2010-09-12T06:55:00.000 | 0 | 0 | 1 | 0 | 0 | python,information-retrieval | 0 | 3,694,041 | 0 | 6 | 0 | false | 0 | 0 | Something like this?
word = 'something'
l = [0,2,4,5,8]
myDict = {}
myDict[word] = l
#Parse some more
myDict[word].append(DocID) | 1 | 2 | 0 | 0 | I know how python dictionaries store key: value tuples. In the project I'm working on, I'm required to store key associated with a value that's a list.
ex:
key -> [0,2,4,5,8]
where,
key is a word from text file
the list value contains ints that stand for the DocIDs in which the word occurs.
as soon as I find the same word in another doc, i need to append that DocID to the list.
How can I achieve this? | Python: Storing a list value associated with a key in dictionary | 0 | 0 | 1 | 0 | 0 | 14,894 |
3,694,051 | 2010-09-12T07:07:00.000 | 1 | 0 | 1 | 1 | 0 | python,windows,directory,traversal | 0 | 3,696,438 | 0 | 1 | 0 | false | 0 | 0 | In a nutshell, here's what you'll need to do.
You can delete the files and folders by using the remove() and rmdir() or removedirs() methods in the os module (assuming your user/program has administrative rights).
To restart your script you will first need to add some command line argument handling to it that allows it to be told whether to start from the beginning or continue from the other point.
To get the script to run after restart, you'll need to set a value in the Windows registry. I believe they're stored under the HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\RunOnceand HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\RunOncekeys. There you can add a string value (type REG_SZ) which contains a command line to invoke your script and pass it the appropriate command line argument(s) which will tell it to continue and re-install the program. | 1 | 0 | 0 | 0 | I want to remove a incorrectly installed program and reinstall it. I can remove the program with subprocess.Popen calling the msiexe on it and install new program the same way BUT ONLY with two independent scripts. But i also need to remove some folders in C:\Programs files and also in C:\Doc& Settings. How can i traverse through the directory structure and remove the folders?Also how can i continue the script after restart the PC from the next line to install the new program. | windows python script to traverse directory to remove folders, restart PC and continue the next line of the script? | 0 | 0.197375 | 1 | 0 | 0 | 472 |
3,694,226 | 2010-09-12T08:35:00.000 | 0 | 0 | 1 | 0 | 0 | python-3.x | 0 | 3,701,970 | 0 | 2 | 0 | false | 0 | 0 | You can use sys.stderr from the sys module. print() uses sys.stdout by default.
import sys
# Print to standard output stream
print("Normal output...")
# Print to standard error stream
print("Error output...", file=sys.stderr) | 1 | 0 | 0 | 0 | how can i receive the console output of any python file (errors, everything printed using the print() command)?
example:
main.py starts test.py and gets its output | get console output | 0 | 0 | 1 | 0 | 0 | 1,180 |
3,696,124 | 2010-09-12T18:56:00.000 | 0 | 0 | 0 | 1 | 0 | python,macos | 0 | 61,142,084 | 0 | 4 | 0 | false | 0 | 0 | i managed to fixed mine by removing python2, i don't if it's a good practice | 1 | 18 | 0 | 0 | I would like to change my PATH from Python 2.6.1 to 3.1.2. I have both versions installed on my computer, but when I type python --version in the terminal I get Python 2.6.1. So, thats the current version it's "pointing" to. Now if I type python3.1 it loads the version I want to use, although the PATH is still pointing to 2.6.1. Downloaded along with the Python 3.1 package comes an Update Shell Profile.command - when I run it and then run nano ~/.bash_profile it says:
Setting PATH for Python 3.1 the orginal version is saved in .bash_profile.pysave
PATH="/Library/Frameworks/Python.framework/Versions/3.1/bin:${PATH}"
export PATH.
Does this mean that I have changed the PATH, or does it just giving me instructions how to? | changing python path on mac? | 0 | 0 | 1 | 0 | 0 | 91,910 |
3,697,628 | 2010-09-13T02:57:00.000 | 7 | 0 | 1 | 0 | 0 | python,textmate | 0 | 3,697,633 | 0 | 2 | 0 | true | 0 | 0 | Option+Shift+Tab (or Cmd+]).
Omitting shift (or changing ] to [) will indent instead of reverse-indent. | 1 | 4 | 0 | 0 | I have a block of code selected, I want to un-indent this selected code.
On a pc, I would do a shift-tab and it would un-indent. | In textmate, how do I reverse indent a block of selected code? | 0 | 1.2 | 1 | 0 | 0 | 4,349 |
3,698,051 | 2010-09-13T05:46:00.000 | 0 | 0 | 1 | 0 | 1 | python,session,queue,multiprocessing | 0 | 3,698,555 | 0 | 3 | 0 | false | 0 | 0 | I am not sure about the requirement to open a separate process for every message received from the sockets. I guess, you have a reason for doing all that you have mentioned.
My understanding is, you have written a server side socket that listens for client connection, accepts the client connection, receives the data and dispatch these data to various processes you have created to handle these messages.
I am assuming that session id remains same for a client connection. Each client sends data tagged with it's session id. If this is the case, then you can solve easily by the fact that in unix - forks duplicate file / socket descriptors. when you launch a multiprocessing.Process(), you can pass it the socket descriptor. Ensure that you close the socket in parent process or the process in which you listen for client connections. This way each process will handle the connection and will receive only messages for the single client tagged with the same session id.
I hope this answers your need. | 1 | 0 | 0 | 0 | I have a script receiveing data from a socket, each data contains a sessionid that a have to keep track of, foreach incomming message, i'm opening a new process with the multiprocessing module, i having trouble to figure out a way to keep track of the new incoming messages having the same sessionid. For example:
100100|Hello --
(open a new process)
100100|Hello back at you
(proccess replies)
100101|Hello
(open a new process)
100101|Hello back at you
(new proccess replies)
100100|wasap? --
(open a new process)
when a new message from sessionid 100100 comes... how could i sent it to the process that is handling those particular messages?
until know the main process is opening a new process for each incomming message another process is writing data on the socket, but is giving me real trouble finding out a way to handle each session process and sending data to them...
I need some guidance cause a never work with multiprocessing before...
Thanks... | Python multiprocessing handling sessions | 0 | 0 | 1 | 0 | 0 | 1,058 |
3,699,268 | 2010-09-13T09:41:00.000 | 0 | 0 | 0 | 1 | 0 | python,django,web-services,api,soap | 0 | 3,699,299 | 0 | 3 | 0 | false | 0 | 0 | Depends on how you want to design your software.
You could do stand-alone scripts as servers listening for requests on specific ports,
or you could use a webserver which runs python scripts so you just have to access a URL.
REST is one option to implement the latter.
You should then look for frameworks for REST development with python, or if it’s simple logic with not so many possible requests can do it on your own as a web-script. | 1 | 1 | 0 | 1 | How can we call the CLI executables commands using Python
For example i have 3 linux servers which are at the remote location and i want to execute some commands on those servers like finding the version of the operating system or executing any other commands. So how can we do this in Python. I know this is done through some sort of web service (SOAP or REST) or API but i am not sure....... So could you all please guide me. | How can we call the CLI executables commands using Python | 0 | 0 | 1 | 0 | 1 | 170 |
3,703,704 | 2010-09-13T19:29:00.000 | 2 | 1 | 1 | 0 | 0 | java,python,dynamic-languages | 0 | 3,703,964 | 0 | 3 | 0 | false | 0 | 0 | Some things that struck me when first trying out Python (coming from a mainly Java background):
Write Pythonic code. Use idioms recommended for Python, rather than doing it the old Java/C way. This is more than just a cosmetic or dogmatic issue. Pythonic code is actually hugely faster in practice than C-like code practically all the time. As a matter of fact, IMHO a lot of the "Python is slow" notion floating around is due to the fact that inexperienced coders tried to code Java/C in Python and ended up taking a big performance hit and got the idea that Python is horribly slow. Use list comprehensions and map/filter/reduce whenever possible.
Get comfortable with the idea that functions are truly objects. Pass them around as callbacks, make functions return functions, learn about closures etc.
There are a lot of cool and almost magical stuff you can do in Python like renaming methods as you mention. These things are great to show off Python's features, but really not necessary if you don't need them. Indeed, as S. Lott pointed out, its better to avoid things that seem risky. | 2 | 6 | 0 | 0 | What are the top gotchas for someone moving from a static lang (java/c#) to dynamic language like python?
It seems cool how things can be done, but renaming a method, or adding/removing parameters seems so risky!
Is the only solution to write tests for each method? | top gotchas for someone moving from a static lang (java/c#) to dynamic language like python | 0 | 0.132549 | 1 | 0 | 0 | 248 |
3,703,704 | 2010-09-13T19:29:00.000 | 3 | 1 | 1 | 0 | 0 | java,python,dynamic-languages | 0 | 3,703,732 | 0 | 3 | 0 | false | 0 | 0 | "Is the only solution to write tests for each method?"
Are you saying you didn't write tests for each method in Java?
If you wrote tests for each method in Java, then -- well -- nothing changes, does it?
renaming a method, seems so risky!
Correct. Don't do it.
adding/removing parameters seems so risky!
What? Are you talking about optional parameters? If so, then having multiple overloaded names in Java seems risky and confusing. Having optional parameters seems simpler.
If you search on SO for the most common Python questions, you'll find that some things are chronic questions.
How to update the PYTHONPATH.
Why some random floating-point calculation isn't the same as a mathematical abstraction might indicate.
Using Python 3 and typing code from a Python 2 tutorial.
Why Python doesn't have super-complex protected, private and public declarations.
Why Python doesn't have an enum type.
The #1 chronic problem seems to be using mutable objects as default values for a function. Simply avoid this. | 2 | 6 | 0 | 0 | What are the top gotchas for someone moving from a static lang (java/c#) to dynamic language like python?
It seems cool how things can be done, but renaming a method, or adding/removing parameters seems so risky!
Is the only solution to write tests for each method? | top gotchas for someone moving from a static lang (java/c#) to dynamic language like python | 0 | 0.197375 | 1 | 0 | 0 | 248 |
3,706,128 | 2010-09-14T04:25:00.000 | 0 | 0 | 0 | 0 | 0 | python,windows | 0 | 5,380,835 | 0 | 2 | 0 | false | 0 | 0 | If you are using pyhook, event.WindowName in your OnKeyboardEvent etc function contains the value xx | 1 | 1 | 0 | 0 | How can I get the window name?
I want to make a script where I have some keyboard event, and I want it to happens only if the window name has something in the name, like, Firefox.
how can I do it?
the simplest way | how can I get the window name? [Python] | 0 | 0 | 1 | 0 | 0 | 4,493 |
3,712,992 | 2010-09-14T21:17:00.000 | 0 | 0 | 0 | 1 | 0 | python,windows | 0 | 3,954,806 | 0 | 2 | 0 | true | 0 | 0 | I had to use remote registry...
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion
ProductName, EditionID, CurrentVersion, CurrentBuild | 1 | 1 | 0 | 1 | So of course I'm new to Python and to programming in general...
I am trying to get OS version information from the network. For now I only care about the windows machines.
using PyWin32 I can get some basic information, but it's not very reliable. This is an example of what I am doing right now: win32net.NetWkstaGetInfo(myip, 100)
However, it appears as though this would provide me with more appropriate information: platform.win32_ver()
I have no idea how get the info from a remote machine using this. I need to specify an IP or a range of IP's... I intend on using Google's ipaddr to get a list of network ranges to scan. I will eventually need to scan a large network for this info.
Can someone provide an example? | Python: How to use platform.win32_ver() on a remote machine? | 1 | 1.2 | 1 | 0 | 0 | 1,156 |
3,718,322 | 2010-09-15T13:56:00.000 | 1 | 0 | 1 | 0 | 0 | python | 0 | 3,718,337 | 0 | 3 | 0 | false | 0 | 0 | use %%.......... | 1 | 1 | 0 | 0 | I am trying to pass a string which has a '%' in it (its actually a sql query string). How do I pass the % (do I have to use a specific escape character?
eg:
compute_answertime("%how do I%") | What is the escape character for % in python's string method | 0 | 0.066568 | 1 | 0 | 0 | 179 |
3,724,238 | 2010-09-16T06:35:00.000 | 1 | 0 | 1 | 1 | 0 | python,process,subprocess,parent-child | 0 | 3,724,308 | 0 | 2 | 0 | false | 0 | 0 | I guess, you are asking, how do you find if the child process is hung while operating. You can't tell easily. A process could be doing a long running operation. The context is important to understand when a process is hung.
If you are expecting a process to respond to a user input and is not responsive for a long period then we consider it hung. Process is running probably waiting for some thing that will never happen. "Hung Process" is humanly way of saying that a program has reached a dead end and will be no more useful.
You could have a program calculating prime numbers one after another and can run for eons and can not be called a hung process. | 2 | 2 | 0 | 0 | How do I know is there my child process got hang while operating? | Python subprocess how to determine if child process hangs? | 0 | 0.099668 | 1 | 0 | 0 | 2,476 |
3,724,238 | 2010-09-16T06:35:00.000 | 2 | 0 | 1 | 1 | 0 | python,process,subprocess,parent-child | 0 | 3,724,322 | 0 | 2 | 0 | true | 0 | 0 | Well, how do you tell the difference between a stuck process and a process that takes longer than usual to complete? The short answer is: No, you can't detect if your child process is stuck.
I would say that to be able to detect this you need some kind of continuous communication with the process (e.g. look at log files, IPC or similar). Based on this communication you might be able to tell when and if a process is stuck. | 2 | 2 | 0 | 0 | How do I know is there my child process got hang while operating? | Python subprocess how to determine if child process hangs? | 0 | 1.2 | 1 | 0 | 0 | 2,476 |
3,728,310 | 2010-09-16T15:42:00.000 | 0 | 0 | 1 | 1 | 1 | python,netbeans | 1 | 3,743,725 | 0 | 1 | 0 | false | 1 | 0 | You probably want to ask this question on www.serverfault.com rather than stackoverflow as it is more of a configuration issue rather than a programming issue.
Include the version of Netbeans and the Java you are using - and whether you using native python and/or Jython as well.
Also include at which point you see the error message - when you create a new file, new project etc - does Netbeans start up ok etc ? | 1 | 1 | 0 | 0 | I have x64 Windows XP machine.
I use Netbeans to code Java.
I am now trying to use it for Python, but I get this error:
\NetBeans was unexpected at this time.
Any idea how to fix it? | Using Python in Netbeans | 0 | 0 | 1 | 0 | 0 | 486 |
3,731,681 | 2010-09-16T23:41:00.000 | 2 | 0 | 1 | 0 | 0 | python,linux,input,interrupt | 0 | 3,731,809 | 0 | 6 | 0 | false | 0 | 0 | You need a separate process (or possibly a thread) to read the terminal and send it to the process of interest via some form of inter-process communication (IPC) (inter-thread communication may be harder -- basically the only thing you do is send a KeyboardInterrupt from a secondary thread to the main thread). Since you say "I was hoping there would be a simple way to inject user input into the loop other than just ^C", I'm sad to disappoint you, but that's the truth: there are ways to do what you request, but simple they aren't. | 2 | 3 | 0 | 0 | Is there a way to send an interrupt to a python module when the user inputs something in the console? For example, if I'm running an infinite while loop, i can surround it with a try/except for KeyboardInterrupt and then do what I need to do in the except block.
Is there a way to duplicate this functionality with any arbitrary input? Either a control sequence or a standard character?
Edit: Sorry, this is on linux | Capturing user input at arbitrary times in python | 0 | 0.066568 | 1 | 0 | 0 | 2,997 |
3,731,681 | 2010-09-16T23:41:00.000 | 1 | 0 | 1 | 0 | 0 | python,linux,input,interrupt | 0 | 3,731,716 | 0 | 6 | 0 | false | 0 | 0 | KeyboardInterrupt is special in that it can be trapped (i.e. SIGINT under operating systems with respective POSIX support, SetConsoleCtrlHandler on Windows) and handled accordingly. If you want to process user input while at the same time doing work in a otherwise blocking loop, have a look at the threading or subprocess modules, taking a look at how to exchange data between two different threads / processes. Also be sure to get an understanding of the issues that go hand in hand with parallel computing (i.e. race conditions, thread safety / synchronization etc.) | 2 | 3 | 0 | 0 | Is there a way to send an interrupt to a python module when the user inputs something in the console? For example, if I'm running an infinite while loop, i can surround it with a try/except for KeyboardInterrupt and then do what I need to do in the except block.
Is there a way to duplicate this functionality with any arbitrary input? Either a control sequence or a standard character?
Edit: Sorry, this is on linux | Capturing user input at arbitrary times in python | 0 | 0.033321 | 1 | 0 | 0 | 2,997 |
3,736,311 | 2010-09-17T14:39:00.000 | 1 | 0 | 1 | 0 | 1 | python,pychecker | 0 | 4,782,453 | 0 | 3 | 0 | false | 0 | 0 | On the bonus extra question:
pychecker always imports the files you pass it, which causes it to import whatever those import. This is just like Python. This is a first pass in pychecker.
Then pychecker will actually go through the loaded modules, disassemble the code, and run through all the opcodes. This is a second pass.
In both cases, it tracks all warnings generated even by ignored modules. Then it filters out those warnings before showing them.
I am considering if it is worth it to change pychecker to not even look at blacklisted modules at all, or make it possible to only disassemble the one file (for integration in an editor for example). | 1 | 1 | 0 | 1 | One of the modules I import into my python project triggers lots of warnings under Pychecker. Fixing up this external module isn't really an option, so I want to tell Pychecker to ignore it.
Does anyone know how to do this? I'm sure it's possible, and probably quite simple, but after trawling Google for a while I've not found any documentation or examples.
Thanks,
Sam
Edit: I can't tag this with 'pychecker' unfortunately as that tag doesn't exist yet and my rep is too low to create.
Edit 2 Bonus extra question: does pychecker check ignored modules anyway, and just not print anything it finds? or do you get some speedup by ignoring some modules? | How can I tell Pychecker to ignore an imported library? | 0 | 0.066568 | 1 | 0 | 0 | 1,754 |
3,736,606 | 2010-09-17T15:15:00.000 | 4 | 1 | 0 | 0 | 0 | python,http,cherrypy | 0 | 3,737,124 | 0 | 2 | 0 | true | 0 | 0 | CherryPy has a caching Tool, but it's never on by default. Most HTTP responses are cacheable by default, though, so look for an intermediate cache between your client and server. Look at the browser first.
If you're not sure whether or not your content is being cached, compare the Date response header to the current time. | 1 | 3 | 0 | 0 | Is it possible that CherryPy, in its default configuration, is caching the responses to one or more of my request handlers? And, if so, how do I turn that off? | How to determine if CherryPy is caching responses? | 1 | 1.2 | 1 | 0 | 1 | 2,007 |
3,739,296 | 2010-09-17T21:47:00.000 | 1 | 0 | 0 | 0 | 0 | javascript,python,streaming,real-time | 0 | 3,739,311 | 0 | 5 | 0 | false | 0 | 0 | You could have the python script write an xml file that you get with an ajax request in your web page, and get the status info from that. | 1 | 4 | 0 | 0 | I have a simple workflow [Step 0]->[1]->[2]->...->[Step N]. The master program knows the step (state) it is currently at.
I want to stream this in real time to a website (in the local area network) so that when my colleagues open, say, http://thecomputer:8000, they can see a real time rendering of the current state of our workflow with any relevant details.
I've tought about writing the state of the script to an StringIO object (streaming to it) and use Javascript to refresh the browser, but I honestly have no idea how to actually do this.
Any advice? | Streaming the state of a Python script to a website | 0 | 0.039979 | 1 | 0 | 1 | 880 |
3,740,903 | 2010-09-18T08:29:00.000 | 2 | 0 | 0 | 0 | 0 | python,dbus | 0 | 13,629,355 | 0 | 2 | 0 | false | 0 | 0 | this example does not work I think because :
'''
The available properties and whether they are writable can be determined by calling org.freedesktop.DBus.Introspectable.Introspect, see the section called “org.freedesktop.DBus.Introspectable”.
'''
and in introspection data the property are missing:
I use dbus-python-1.1.1 | 1 | 6 | 0 | 0 | In all python dbus documentations there are info on how to export objects, interfaces, signals, but there is nothing how to export interface property.
Any ideas how to do that ? | Python Dbus : How to export Interface property | 0 | 0.197375 | 1 | 0 | 0 | 5,868 |
3,742,583 | 2010-09-18T16:55:00.000 | 1 | 0 | 1 | 1 | 0 | python,windows-installer,metadata,md5 | 0 | 3,742,782 | 0 | 4 | 0 | false | 0 | 0 | To answer your second question: no, there is no way to hash a PE file or ZIP file, ignoring the metadata, without locating and reading the metadata. This is because the metadata you're interested in is stored at variable locations in the file.
In the case of PE files (EXE, DLL, etc), it's stored in a resource block, typically towards the end of the file, and a series of pointers and tables at the start of the file gives the location.
In the case of ZIP files, it's scattered throughout the archive -- each included file is preceded by its own metadata, and then there's a table at the end giving the locations of each metadata block. But it sounds like you might actually be wanting to read the files within the ZIP archive and look for EXEs in there if you're after program metadata; the ZIP archive itself does not store company names or version numbers. | 1 | 7 | 0 | 0 | I am writing a Python script to index a large set of Windows installers into a DB.
I would like top know how to read the metadata information (Company, Product Name, Version, etc) from EXE, MSI and ZIP files using Python running on Linux.
Software
I am using Python 2.6.5 on Ubuntu 10.04 64-bit with Django 1.2.1.
Found so far:
Windows command line utilities that can extract EXE metadata (like filever from SysUtils), or other individual CL utils that only work in Windows. I've tried running these through Wine but they have problems and it hasn't been worth the work to go and find the libs and frameworks that those CL utils depend on and try installing them in Wine/Crossover.
Win32 modules for Python that can do some things but won't run in Linux (right?)
Secondary question:
Obviously changing the file's metadata would change the MD5 hashsum of the file. Is there a general method of hashing a file independent of the metadata besides locating it and reading it in (ex: like skipping the first 1024 byes?) | Read EXE, MSI, and ZIP file metadata in Python in Linux | 0 | 0.049958 | 1 | 0 | 0 | 4,161 |
3,743,329 | 2010-09-18T20:13:00.000 | 5 | 0 | 0 | 0 | 0 | python,database,django,class | 0 | 3,743,351 | 0 | 2 | 0 | true | 1 | 0 | Do not store code in the database!!!
Imagine a class with a malicious __init__ method finding it's way in your "class repository" in the database. This means whoever has write access to those database tables has the ability to read any file from your web server and even nuke it's file system, since they have the ability to execute any python code on it. | 1 | 2 | 0 | 0 | I'm using Django and want to be able to store classes in a database for things like forms and models so that I can easily make them creatable through a user interface since they are just stored in the database as opposed to a regular file. I don't really know a whole lot about this and am not sure if this is a situation where I need to use exec in python or if there is some other way. My searches on this aren't turning up much of anything.
Basically, it would just be where I do a database call and get the contents of a class, then I want to instantiate it. Any advice is appreciated on how to best do this sort of thing.
EDIT: In response to the idea of a malicious __init__ in the class, these are only for things like forms or models where it is tightly controlled through validation what goes in the class, there would never be an __init__ in the class and it would be basically impossible, since I would validate everything server side, to put anything malicious in the class. | Python, how to instantiate classes from a class stored in a database? | 1 | 1.2 | 1 | 0 | 0 | 262 |
3,743,812 | 2010-09-18T22:43:00.000 | 0 | 0 | 0 | 1 | 0 | python,linux,windows,shell,osx-leopard | 0 | 3,743,825 | 0 | 2 | 0 | false | 0 | 0 | All of those operating systems should support a PATH environment variable which specifies directories that have executables that should be available everywhere. Make your script executable by chmod +x and place it into one of those directories (or add a new one to your PATH - I have ~/bin for instance).
I don't know how to make new kinds of files directly executable on Windows, though, but I guess you could use a .bat file as a proxy. | 1 | 3 | 0 | 0 | Can someone tell me how to make my script callable in any directory?
My script simply returns the number of files in a directory. I would like it to work in any directory by invoking it, instead of first being copied there and then typing python myscript.py
I am using Mac OS X, but is there a common way to get it installed on Windows and Linux? | Making Python script accessible system wide | 1 | 0 | 1 | 0 | 0 | 3,533 |
3,746,790 | 2010-09-19T17:50:00.000 | 0 | 0 | 0 | 0 | 0 | python,django,django-models | 0 | 3,746,881 | 0 | 2 | 0 | false | 1 | 0 | If you are okay with changing these setting programmatically via settings.py you should do that. However, if you want to change these settings via the Admin Console, you should use models. | 1 | 1 | 0 | 0 | I want to keep some global settings for my project in Django. I need to have access to these settings from the code. For example, I need to set a current theme for my site that I can set using admin console or from the code. Or I need to set a tagline that will show in the header of all pages. I suppose I should use models for keeping the settings but I can't realize how I should better do it. | How to work with settings in Django | 0 | 0 | 1 | 0 | 0 | 108 |
3,748,720 | 2010-09-20T04:31:00.000 | 7 | 1 | 1 | 0 | 0 | python | 0 | 3,748,735 | 0 | 2 | 0 | false | 0 | 0 | Assuming you're already familiar with another programming language:
Time to learn python basics: 1 week.
Total time to figure out email module: 2 days.
Total time to figure out httplib module: 1 days.
Total time to figure out creating database: 3 days.
Total time to learn about SQL: 2 weeks.
Total time to figure out that you probably don't need SQL: 1 week.
Total time writing the rest of the logic in python: 1 week.
Probably... | 2 | 1 | 0 | 0 | I have been wanting to get into Python for a while now and have accumulated quite a few links to tutorials, books, getting started guides and the like. I have done a little programming in PERL and PHP, but mostly just basic stuff.
I'd like to be able to set expectations for myself, so based on the following requirements how long do you think it will take to get this app up and running?
Online Collection DB
Users can create accounts that are authenticated through token sent via e-mail
Once logged in, users can add items to pre-created collections (like "DVD" or "Software")
Each collection has it's own template with attributes (ie: DVD has Name, Year, Studio, Rating, Comments, etc)
Users can list all items in collections (all DVDs, all Software), sort by various attributes
Also: Yes I know there are lots of online tools like this, but I want to build it on my own with Python | Complete newbie excited about Python. How hard would this app be to build? | 0 | 1 | 1 | 0 | 0 | 221 |
3,748,720 | 2010-09-20T04:31:00.000 | 0 | 1 | 1 | 0 | 0 | python | 0 | 3,748,731 | 0 | 2 | 0 | false | 0 | 0 | Assuming that you don't write everything from the ground up and reuse basic components, this shouldn't be too hard. Probably the most difficult aspect will be authentication, because that requires domain specific knowledge and is hard to get right in any language. I would suggest starting with the basic functionality, even maybe learn how to get it up and running on App Engine, and then once you have the basic functionality, then you can deal with the business of authentication and users. | 2 | 1 | 0 | 0 | I have been wanting to get into Python for a while now and have accumulated quite a few links to tutorials, books, getting started guides and the like. I have done a little programming in PERL and PHP, but mostly just basic stuff.
I'd like to be able to set expectations for myself, so based on the following requirements how long do you think it will take to get this app up and running?
Online Collection DB
Users can create accounts that are authenticated through token sent via e-mail
Once logged in, users can add items to pre-created collections (like "DVD" or "Software")
Each collection has it's own template with attributes (ie: DVD has Name, Year, Studio, Rating, Comments, etc)
Users can list all items in collections (all DVDs, all Software), sort by various attributes
Also: Yes I know there are lots of online tools like this, but I want to build it on my own with Python | Complete newbie excited about Python. How hard would this app be to build? | 0 | 0 | 1 | 0 | 0 | 221 |
3,752,154 | 2010-09-20T13:58:00.000 | 0 | 0 | 1 | 0 | 0 | python | 0 | 3,777,996 | 0 | 1 | 0 | true | 1 | 0 | should be 'className' in IE... | 1 | 0 | 0 | 0 | I wrote the sentence as follows:
allLinkValues = ie.getLinksValue('class')
but the return values are all None, don't know why... | how to get the value of the 'class' attribute in a link? | 0 | 1.2 | 1 | 0 | 0 | 34 |
3,758,468 | 2010-09-21T08:20:00.000 | 1 | 0 | 0 | 0 | 0 | python,wxpython | 0 | 3,758,497 | 0 | 1 | 1 | true | 0 | 1 | I think you could do 2 progress bars, one for files, and second for line in just read file. This will be similar to copy progress in TotalCommander.
If you want one progress bar you could just count file sizes using os.path.getsize(path) and then show how many bytes have you processed/bytes total. | 1 | 0 | 0 | 0 | I have wxpython application that run over a list of files on some directory and proccess the files line by line
I need to build a progress bar that show the status how records already done with wx.gauge control
I need to count the number of the records before i use the wx.guage in order to build the progress bar ,
is this the way to do this and if yes what is the best method to count the number of lines of all the files on some directory with pyhon ? | counting records of files on directory with python | 1 | 1.2 | 1 | 0 | 0 | 222 |
3,758,509 | 2010-09-21T08:28:00.000 | 9 | 0 | 0 | 0 | 1 | python,django,customization,admin | 0 | 3,759,347 | 0 | 2 | 0 | true | 1 | 0 | Slow down. Relax. Follow the Django philosophy.
You have an "app". It presents data. Focus on presentation.
You have a default, built-in admin for your "app". It updates data and it's already there.
If the admin app doesn't meet your needs update Forms and update Models to get close. But don't strain yourself messing with admin. Get as close as you can. But relax about it.
[Also, "more intuitive admin" is sometimes not an accurate description of what you're trying to do. It could be, but I've seen some "more intuitive" that actually wasn't.]
a more designed and intuitive admin interface for the client.
Is this part of the app? Does the app do more than simply present data?
If the app is transactional -- add, change, delete -- crud rules -- that kind of thing, then that's your app. If you want a fancy UI, that's not admin any more. There's no redirect. That's your app.
It's just coding. Stop messing with admin and start writing your app.
Hint: Use generic views as much as possible.
Other than that, you're talking about your app, not hacking the admin stuff that already works.
if you know how to hack the admin views and templates to your heart's content you are not a semi-pro
Wrong. All the source is there. You can read it, also. That's what the pros do. We read the source. And we don't hack the admin app.
If you have complex transactions, you have a first-class, for-real, actual application. Not default admin, but a part of your app that has forms.
If you have forms, then, well, you have forms. This does not require hacking the admin app, it's just coding more of your app. | 1 | 1 | 0 | 0 | I am new to django and have gotten a bit stuck on trying to make the admin site work as I'd like it to. I am wondering if for making the admin functionality I want it is better to make a custom admin app with a template inheriting from admin/base_site.html, using the frontend login with a redirect when is_staff is true.
The initial details that make me think this:
I have a chain of foreignkeys and would like to display nested inlines on the parent admin page. I have tried using easymode, but it's got its own issues and requirements that may cause headaches later i can do without.
I would like to add a function allowing the admin to add an instance of a model, which triggers the creation of instances its related models and redirects etc. This requires adding some callables at least, which I havent figured out yet how to really do with any success in the admin model, and at the moment seems easier to just quickly do this in the views.py of my own app rather than trying to toy with the admin views.
In general, creating a custom admin app (using a is_staff=true redirect on the FrontEnd login) seems more flexible in the long run, and will result in a more designed and intuitive admin interface for the client - so I suppose my question is, what are the semi-pros doing? (if you know how to hack the admin views and templates to your heart's content you are not a semi-pro :) )
Thanks for any advice you can offer, Im still getting my feet wet and this kind of advice could save me alot of time and headache. | Customizing Django Admin Interface functionality | 0 | 1.2 | 1 | 0 | 0 | 4,748 |
3,758,648 | 2010-09-21T08:48:00.000 | 13 | 0 | 0 | 0 | 1 | python,pyqt,pyside | 0 | 3,761,216 | 0 | 1 | 0 | true | 0 | 1 | u need to import QtCore
so the code will look like this :
self.setWindowFlags(QtCore.Qt.FramelessWindowHint)
whenever you see Qt.something put in mind that they are talking about the Qt class inside QtCore module .
hope this helps | 1 | 7 | 0 | 0 | I've been looking for how to do this and I've found places where the subject comes up, but none of the suggestions actually work for me, even though they seem to work out okay for the questioner (they don't even list what to import). I ran across self.setWindowFlags(Qt.FramelessWindowHint) but it doesn't seem to work regardless of the import I try (QtGui.FramelessWindowHint, QtCore.FramelessWindowHint, etc.).
Any ideas? | Setting window style in PyQT/PySide? | 0 | 1.2 | 1 | 0 | 0 | 6,028 |
3,758,658 | 2010-09-21T08:49:00.000 | 1 | 0 | 0 | 0 | 0 | javascript,jquery,python,matplotlib,hyperlink | 0 | 3,759,346 | 0 | 2 | 1 | false | 0 | 0 | You can do this with an imagemap or HTML element overlay controlled by JavaScript/jQuery.
Essentially, send your chart data to the page along with the chart image, and use JS to create the elements with the links according to the specification of the data.
It's a bit harder than the bar graphs I've done this to before, but should work fine. | 1 | 3 | 0 | 0 | I want to do a pie chart in matplotlib.
This pie chart will be a representation of two variables: male and female.
That's easy to do :)
What I would like to do next, I'm not even sure if it's possible to do with matplotlib, I would like to make these two variables clickable so if I click on male, I would see another page with information about this, same thing with female.
Image map isn't a solution since this variables may change in the future.
Anyone has any idea how to do this? If it's possible with matplotlib or what program would you recommend.
Thank you! | how to create hyperlink in piechart | 0 | 0.099668 | 1 | 0 | 0 | 1,491 |
3,759,003 | 2010-09-21T09:37:00.000 | 0 | 0 | 0 | 0 | 0 | python,django,google-app-engine,django-models,google-cloud-datastore | 1 | 3,808,459 | 0 | 3 | 0 | true | 1 | 0 | Two possible solutions:
Check if the reference still exists, before you access it:
if not obj.reference:
# Referenced entity was deleted
When you delete a model object that may be referenced, query all models that might reference it, and set their reference property to None. | 3 | 1 | 0 | 0 | I am working on an application on Django and google application engine. In my application I have several models with several ReferenceProperty fields. The issue is that if any of the ReferenceProperty field gets deleted it produces a ReferenceProperty related errors in all the other models where it has been used. What I want is, when a field is deleted say a User is deleted, all the fields having User as the ReferenceProperty should still work without any error messages displaying the associated user as unavailable or something like that.
Can someone please suggest how that can be done?
Thanks in advance. | Django Google app engine reference issues | 0 | 1.2 | 1 | 0 | 0 | 249 |
3,759,003 | 2010-09-21T09:37:00.000 | 0 | 0 | 0 | 0 | 0 | python,django,google-app-engine,django-models,google-cloud-datastore | 1 | 3,759,035 | 0 | 3 | 0 | false | 1 | 0 | When I have the same problem ago, I could not find a general solution. The only way I found is to do try/except for every reference property. If you find another answer post it here. | 3 | 1 | 0 | 0 | I am working on an application on Django and google application engine. In my application I have several models with several ReferenceProperty fields. The issue is that if any of the ReferenceProperty field gets deleted it produces a ReferenceProperty related errors in all the other models where it has been used. What I want is, when a field is deleted say a User is deleted, all the fields having User as the ReferenceProperty should still work without any error messages displaying the associated user as unavailable or something like that.
Can someone please suggest how that can be done?
Thanks in advance. | Django Google app engine reference issues | 0 | 0 | 1 | 0 | 0 | 249 |
3,759,003 | 2010-09-21T09:37:00.000 | 1 | 0 | 0 | 0 | 0 | python,django,google-app-engine,django-models,google-cloud-datastore | 1 | 3,808,505 | 0 | 3 | 0 | false | 1 | 0 | You could also just set a flag, say deleted, on the entity you're deleting, and then leave it in the datastore. This has the advantage of avoiding all referential integrity problems in the first place, but it comes at the cost of two main disadvantages:
All your existing queries need to be changed to deal with entities that have the deleted property set, either by omitting them from the result set or by special casing them somehow.
"Deleted" data stays in the datastore; this can bloat the datastore, and also may not be an option for sensitive information.
This doesn't really solve your problem at all, but I thought I'd mention it for completeness's sake. | 3 | 1 | 0 | 0 | I am working on an application on Django and google application engine. In my application I have several models with several ReferenceProperty fields. The issue is that if any of the ReferenceProperty field gets deleted it produces a ReferenceProperty related errors in all the other models where it has been used. What I want is, when a field is deleted say a User is deleted, all the fields having User as the ReferenceProperty should still work without any error messages displaying the associated user as unavailable or something like that.
Can someone please suggest how that can be done?
Thanks in advance. | Django Google app engine reference issues | 0 | 0.066568 | 1 | 0 | 0 | 249 |
3,774,772 | 2010-09-23T01:21:00.000 | 2 | 1 | 0 | 1 | 0 | python,cron,package,execute,at-job | 0 | 3,774,794 | 0 | 4 | 0 | false | 0 | 0 | type man at, it will explain how to use it. Usage will slighty differ from system to system, so there's no use to tell you here exactly. | 1 | 2 | 0 | 0 | When I try to use cron to execute my python script in a future time, I found there is a command at, AFAIK, the cron is for periodically execute, but what my scenario is only execute for once in specified time.
and my question is how to add python script to at command,
also it there some python package for control the at command
My dev os is ubuntu 10.04 lucid,and my product server is ubuntu-server 10.04 lucid version.
in fact, I want through python script add python script tasks to at command, which file's change can effect at command add or remove new jobs | How to use at command to set python script execute at specified time | 0 | 0.099668 | 1 | 0 | 0 | 2,030 |
3,780,379 | 2010-09-23T16:14:00.000 | 0 | 1 | 0 | 0 | 0 | ironpython | 0 | 3,780,791 | 0 | 1 | 0 | false | 0 | 0 | Resolved. Turns out that you need to rebuild IronPython from source, with the command line options –X:Frames or –X:FullFrames. | 1 | 0 | 0 | 0 | I'm trying to use a module that requires sys._getframe(), which, as I understand it, is not enabled by default. I've seen a lot of material that suggests that there is a way to enable _getframe(), but I've yet to find anything that tells me how to do so. What is the proper method for enabling this function in IronPython 2.6.1? Does one even exist? Thanks in advance. | How can I enable sys._getframe in IronPython 2.6.1? | 1 | 0 | 1 | 0 | 0 | 905 |
3,781,873 | 2010-09-23T19:33:00.000 | 0 | 0 | 1 | 1 | 0 | python,pywin32,python-embedding | 0 | 3,782,055 | 0 | 1 | 0 | false | 0 | 0 | I previously used py2exe to freeze the application and all the DLLs. Then use Innosetup to create an installer. Work like a charm. | 1 | 2 | 0 | 0 | I have python as an embedded scripting environment in my application. I supply the python bits (python26.dll, DLLs & Lib folders) with my application. All this to avoid asking users to install python (you know how it goes in big corporations).
All works nice except pywin32. It installs pythoncom26.dll and pywintypes26.dll to the system32 directory. I want to keep these dlls in my Python directory. One option is to add my Python directory to the PATH env variable. But would like to avoid it for obvious reasons (windows DLL search path priorities issues).
Is there a way to tell Windows (a windows API is also fine) to look at my directories to load these pywin32 dlls? From what I understand these dlls get called by Windows COM.
Thanks.
Edit1:
Note that python is deployed embedded with my application. | pywin32 captive installation (avoid py*.dll getting installed in system32 directory) | 0 | 0 | 1 | 0 | 0 | 573 |
3,785,502 | 2010-09-24T08:48:00.000 | 2 | 0 | 0 | 0 | 0 | python,django | 0 | 3,787,861 | 0 | 1 | 0 | true | 1 | 0 | Well I found the answer. It was quite easy actually. you just need to set the FileField value to some string and it will point to that file.
The point is that the path specified should be correct otherwise you get a 404 error when trying to access it. | 1 | 1 | 0 | 0 | I wanted to know how is it possible in django to bind an already uploaded file (stored in the file system of server) to a Model FileField. This way I want to have my edit page of that model to prepopulate the FileField with this file.
Thanks | Prepopulating a Django FileField | 1 | 1.2 | 1 | 0 | 0 | 669 |
3,793,424 | 2010-09-25T10:34:00.000 | 1 | 0 | 0 | 0 | 1 | python,django,subdomain | 0 | 3,794,000 | 0 | 1 | 0 | true | 1 | 0 | You may be able to do what you need with apache mod_rewrite.
Obviously I didn't read the question clearly enough.
As for how to do it in django: you could have some middleware that looks at the server name, and redirects according to that (or even sets a variable). You can't do it with the bare url routing system, as that only has path information, not hostname info. | 1 | 2 | 0 | 0 | What are the best practices and solutions for managing dynamic subdomains in different technologies and frameworks? I am searching for something to implement in my Django project but those solutions that I saw, don't work. I also tried to use Apache rewrite mod to send requests from subdomain.domain.com to domain.com/subdomain but couldn't realize how to do it with Django.
UPDATE: What I need is to create virtual subdomains for my main domain using usernames from the site. So, if I have a new registered user that is called jack, when I go to jack.domain.com, it would operate make some operations. Like if I just went to domain.com/users/jack. But I don't want to create an actual subdomain for each user. | Managing subdomains | 0 | 1.2 | 1 | 0 | 0 | 347 |
3,794,868 | 2010-09-25T17:54:00.000 | 8 | 0 | 1 | 0 | 0 | python,multithreading,thread-safety,thread-local | 0 | 3,794,914 | 0 | 1 | 0 | true | 0 | 0 | No -- thread local means that each thread gets its own copy of that variable. Using it is (at least normally) thread-safe, simply because each thread uses its own variable, separate from variables by the same name that's accessible to other threads. OTOH, they're not (normally) useful for communication between threads. | 1 | 5 | 0 | 0 | Specifically I'm talking about Python. I'm trying to hack something (just a little) by seeing an object's value without ever passing it in, and I'm wondering if it is thread safe to use thread local to do that. Also, how do you even go about doing such a thing? | Does thread-local mean thread safe? | 0 | 1.2 | 1 | 0 | 0 | 718 |
3,798,067 | 2010-09-26T13:49:00.000 | 0 | 0 | 0 | 0 | 0 | python | 0 | 3,805,092 | 0 | 4 | 0 | false | 0 | 0 | Dcolish's answer is good. I'm not sure the idea of executing code that comes in on a network interface is good in itself, though - you will need to take care to verify that you can trust the sending party, especially if this interface is going to be exposed to the Internet or really any production network. | 1 | 0 | 0 | 0 | how do i run a python program that is received by a client from server without writing it into a new python file? | network programming in python | 0 | 0 | 1 | 0 | 1 | 387 |
3,801,379 | 2010-09-27T05:48:00.000 | 61 | 0 | 0 | 0 | 0 | python,django,redis | 0 | 7,722,260 | 0 | 5 | 0 | false | 1 | 0 | Just because Redis stores things in-memory does not mean that it is meant to be a cache. I have seen people using it as a persistent store for data.
That it can be used as a cache is a hint that it is useful as a high-performance storage. If your Redis system goes down though you might loose data that was not been written back onto the disk again. There are some ways to mitigate such dangers, e.g. a hot-standby replica.
If your data is 'mission-critical', like if you run a bank or a shop, Redis might not be the best pick for you. But if you write a high-traffic game with persistent live data or some social-interaction stuff and manage the probability of data-loss to be quite acceptable, then Redis might be worth a look.
Anyway, the point remains, yes, Redis can be used as a database. | 1 | 107 | 0 | 0 | I've heard of redis-cache but how exactly does it work? Is it used as a layer between django and my rdbms, by caching the rdbms queries somehow?
Or is it supposed to be used directly as the database? Which I doubt, since that github page doesn't cover any login details, no setup.. just tells you to set some config property. | How can I use redis with Django? | 0 | 1 | 1 | 1 | 0 | 75,541 |
3,808,581 | 2010-09-27T23:17:00.000 | 0 | 1 | 0 | 0 | 0 | python,apache,embedded,beagleboard | 0 | 3,811,703 | 0 | 4 | 0 | false | 1 | 0 | the device will be mobile and will be moving locations every few days. So, I can't guarantee a static IP address for the device.
Your device can be a client of the web site.
Your web site has two interfaces.
HTML interface to people.
A non-HTML interface to the device. As a client of a web site, the device will need an HTTP client-side library to send a request to the web site. This request will include the device's IP address, plus all the usual malarky buried in an HTTP request. (There are a bunch of standard headers that are sent in a request)
Once the device has made it's initial request, then your web site can save the device's current status and communicate with it through another protocol if you want to do that.
(I'm guessing that "I have all the functional parts written on the server and device side" means you have some other protocol for controlling the device, and this protocol isn't based on HTTP.)
It might be simplest in the long run to have the device poll the web site for commands or updates or things. That way the device is a pure web client using only HTTP, and your web site is a pure web server, using only HTTP. Then you don't need your more specialized second protocol. Using only HTTP means you can use SSL to assure a secure communication.
If your device uses HTTP to get commands and updates, you'll need to work out a usable representation for data that can easily be encoded into HTTP requests and responses. Choices include XML, JSON and YAML. You can always invent your own data format; however, you'll probably be happier debugging a standardized format like JSON.
Building these two interfaces in Django is pretty trivial. You'll simply have some URL's which are for people and some which are for your device. You'll have view functions for people that return HTML pages, and view functions for your device that return JSON or XML messages. | 1 | 5 | 0 | 0 | I'm currently working on a project where I'm trying to control an embedded device through an Internet facing website. The idea is is that a user can go to a website and tell this device to preform some kind of action. An action on the website would be translated into a series of CLI commands and then sent to the device. Communication could potentially go both ways in the future, but right now I'm focusing on server-to-device.
The web server is a LAMP stack using Python (Django) and the device I'm trying to communicate with is a Beagle Board running eLinux. There would be only one device existing at any time communicating to the server.
I have all the functional parts written on the server and device side, but I'm having a bit of trouble figuring out how to write the communication layer. One of my big issues is that the device will be mobile and will be moving locations every few days. So, I can't guarantee a static IP address for the device. My networking programming knowledge is pretty minimal so I don't have that great an idea on where to start.
Does anyone have any ideas/resources on how I can start developing this kind of communication?
Thanks! | Creating a website to communicate with an embedded device | 0 | 0 | 1 | 0 | 0 | 1,776 |
3,809,314 | 2010-09-28T02:40:00.000 | 3 | 0 | 1 | 0 | 0 | python,windows,compatibility,backwards-compatibility,build-environment | 0 | 3,809,331 | 0 | 19 | 0 | false | 0 | 0 | You can install multiple versions of Python one machine, and during setup, you can choose to have one of them associate itself with Python file extensions. If you install modules, there will be different setup packages for different versions, or you can choose which version you want to target. Since they generally install themselves into the site-packages directory of the interpreter version, there shouldn't be any conflicts (but I haven't tested this). To choose which version of python, you would have to manually specify the path to the interpreter if it is not the default one. As far as I know, they would share the same PATH and PYTHONPATH variables, which may be a problem.
Note: I run Windows XP. I have no idea if any of this changes for other versions, but I don't see any reason that it would. | 8 | 234 | 0 | 0 | I do most of my programming in Python 3.x on Windows 7, but now I need to use the Python Imaging Library (PIL), ImageMagick, and wxPython, all of which require Python 2.x.
Can I have both Python 2.x and Python 3.x installed in Windows 7? When I run a script, how would I "choose" which version of Python should run it? Will the aforementioned programs be able to handle multiple versions of Python installed at once? I have searched for hours and hours for how to do this to no avail.
Thanks. | How to install both Python 2.x and Python 3.x in Windows | 0 | 0.031568 | 1 | 0 | 0 | 242,246 |
3,809,314 | 2010-09-28T02:40:00.000 | 81 | 0 | 1 | 0 | 0 | python,windows,compatibility,backwards-compatibility,build-environment | 0 | 22,626,734 | 0 | 19 | 0 | false | 0 | 0 | What I did was download both 2.7.6 and 3.3.4. Python 3.3.4 has the option to add the path to it in the environment variable so that was done. So basically I just manually added Python 2.7.6.
How to...
Start > in the search type in environment select "Edit environment variables to your account"1
Scroll down to Path, select path, click edit.
Add C:\Python27;
so you should have paths to both versions of Python there, but if you don't this you can easily edit it so that you do..... C:\Python27;C:\Python33;
Navigate to the Python27 folder in C:\ and rename a copy of python.exe to python2.exe
Navigate to the Python34 folder in C:\ and rename a copy of python.exe to python3.exe
Test: open up commmand prompt and type python2 ....BOOM! Python 2.7.6. exit out.
Test: open up commmand prompt and type python3 ....BOOM! Python 3.4.3. exit out.
Note: (so as not to break pip commands in step 4 and 5, keep copy of python.exe in the same directory as the renamed file) | 8 | 234 | 0 | 0 | I do most of my programming in Python 3.x on Windows 7, but now I need to use the Python Imaging Library (PIL), ImageMagick, and wxPython, all of which require Python 2.x.
Can I have both Python 2.x and Python 3.x installed in Windows 7? When I run a script, how would I "choose" which version of Python should run it? Will the aforementioned programs be able to handle multiple versions of Python installed at once? I have searched for hours and hours for how to do this to no avail.
Thanks. | How to install both Python 2.x and Python 3.x in Windows | 0 | 1 | 1 | 0 | 0 | 242,246 |
3,809,314 | 2010-09-28T02:40:00.000 | 13 | 0 | 1 | 0 | 0 | python,windows,compatibility,backwards-compatibility,build-environment | 0 | 48,239,658 | 0 | 19 | 0 | false | 0 | 0 | To install and run any version of Python in the same system follow my guide below.
For example say you want to install Python 2.x and Python 3.x on the same Windows system.
Install both of their binary releases anywhere you want.
When prompted do not register their file extensions and
do not add them automatically to the PATH environment variable
Running simply the command python the executable that is first met in PATH will be chosen for launch. In other words, add the Python directories manually. The one you add first will be selected when you type python. Consecutive python programs (increasing order that their directories are placed in PATH) will be chosen like so:
py -2 for the second python
py -3 for the third python etc..
No matter the order of "pythons" you can:
run Python 2.x scripts using the command: py -2 (Python 3.x functionality) (ie. the first Python 2.x installation program found in your PATH will be selected)
run Python 3.x scripts using the command: or py -3 (ie. the first Python 3.x installation program found in your PATH will be selected)
In my example I have Python 2.7.14 installed first and Python 3.5.3. This is how my PATH variable starts with:
PATH=C:\Program Files\Microsoft MPI\Bin\;C:\Python27;C:\Program Files\Python_3.6\Scripts\;C:\Program Files\Python_3.6\;C:\ProgramData\Oracle\Java\javapath;C:\Program Files (x86)\Common Files\Intel\Shared
...
Note that Python 2.7 is first and Python 3.5 second.
So running python command will launch python 2.7 (if Python 3.5 the same command would launch Python 3.5).
Running py -2 launches Python 2.7 (because it happens that the second Python is Python 3.5 which is incompatible with py -2).
Running py -3 launches Python 3.5 (because it's Python 3.x)
If you had another python later in your path you would launch like so: py -4. This may change if/when Python version 4 is released.
Now py -4 or py -5 etc. on my system outputs: Requested Python version (4) not installed or Requested Python version (5) not installed etc.
Hopefully this is clear enough. | 8 | 234 | 0 | 0 | I do most of my programming in Python 3.x on Windows 7, but now I need to use the Python Imaging Library (PIL), ImageMagick, and wxPython, all of which require Python 2.x.
Can I have both Python 2.x and Python 3.x installed in Windows 7? When I run a script, how would I "choose" which version of Python should run it? Will the aforementioned programs be able to handle multiple versions of Python installed at once? I have searched for hours and hours for how to do this to no avail.
Thanks. | How to install both Python 2.x and Python 3.x in Windows | 0 | 1 | 1 | 0 | 0 | 242,246 |
3,809,314 | 2010-09-28T02:40:00.000 | 0 | 0 | 1 | 0 | 0 | python,windows,compatibility,backwards-compatibility,build-environment | 0 | 64,577,951 | 0 | 19 | 0 | false | 0 | 0 | I use a simple solution to switch from a version to another version of python, you can install all version you want. All you have to do is creating some variable environment.
In my case, I have installed python 2.7 and python 3.8.1, so I have created this environment variables:
PYTHON_HOME_2.7=<path_python_2.7>
PYTHON_HOME_3.8.1=<path_python_3.8.1>
PYTHON_HOME=%PYTHON_HOME_2.7%
then in my PATH environment variable I put only %PYTHON_HOME% and %PYTHON_HOME%\Scripts. In the example above I'm using the version 2.7, when I want to switch to the other version I have only to set the PYTHON_HOME=%PYTHON_HOME_3.8.1%.
I use this method to switch quickly from a version to another also for JAVA, MAVEN, GRADLE,ANT, and so on. | 8 | 234 | 0 | 0 | I do most of my programming in Python 3.x on Windows 7, but now I need to use the Python Imaging Library (PIL), ImageMagick, and wxPython, all of which require Python 2.x.
Can I have both Python 2.x and Python 3.x installed in Windows 7? When I run a script, how would I "choose" which version of Python should run it? Will the aforementioned programs be able to handle multiple versions of Python installed at once? I have searched for hours and hours for how to do this to no avail.
Thanks. | How to install both Python 2.x and Python 3.x in Windows | 0 | 0 | 1 | 0 | 0 | 242,246 |
3,809,314 | 2010-09-28T02:40:00.000 | -1 | 0 | 1 | 0 | 0 | python,windows,compatibility,backwards-compatibility,build-environment | 0 | 43,160,074 | 0 | 19 | 0 | false | 0 | 0 | I have installed both python 2.7.13 and python 3.6.1 on windows 10pro and I was getting the same "Fatal error" when I tried pip2 or pip3.
What I did to correct this was to go to the location of python.exe for python 2 and python 3 files and create a copy of each, I then renamed each copy to python2.exe and python3.exe depending on the python version in the installation folder. I therefore had in each python installation folder both a python.exe file and a python2.exe or python3.exe depending on the python version.
This resolved my problem when I typed either pip2 or pip3. | 8 | 234 | 0 | 0 | I do most of my programming in Python 3.x on Windows 7, but now I need to use the Python Imaging Library (PIL), ImageMagick, and wxPython, all of which require Python 2.x.
Can I have both Python 2.x and Python 3.x installed in Windows 7? When I run a script, how would I "choose" which version of Python should run it? Will the aforementioned programs be able to handle multiple versions of Python installed at once? I have searched for hours and hours for how to do this to no avail.
Thanks. | How to install both Python 2.x and Python 3.x in Windows | 0 | -0.010526 | 1 | 0 | 0 | 242,246 |
3,809,314 | 2010-09-28T02:40:00.000 | 1 | 0 | 1 | 0 | 0 | python,windows,compatibility,backwards-compatibility,build-environment | 0 | 33,527,329 | 0 | 19 | 0 | false | 0 | 0 | Check your system environment variables after installing Python, python 3's directories should be first in your PATH variable, then python 2.
Whichever path variable matches first is the one Windows uses.
As always py -2 will launch python2 in this scenario. | 8 | 234 | 0 | 0 | I do most of my programming in Python 3.x on Windows 7, but now I need to use the Python Imaging Library (PIL), ImageMagick, and wxPython, all of which require Python 2.x.
Can I have both Python 2.x and Python 3.x installed in Windows 7? When I run a script, how would I "choose" which version of Python should run it? Will the aforementioned programs be able to handle multiple versions of Python installed at once? I have searched for hours and hours for how to do this to no avail.
Thanks. | How to install both Python 2.x and Python 3.x in Windows | 0 | 0.010526 | 1 | 0 | 0 | 242,246 |
3,809,314 | 2010-09-28T02:40:00.000 | -1 | 0 | 1 | 0 | 0 | python,windows,compatibility,backwards-compatibility,build-environment | 0 | 21,692,110 | 0 | 19 | 0 | false | 0 | 0 | Only Works if your running your code in your Python IDE
I have both Python 2.7 and Python 3.3 installed on my windows operating system. If I try to launch a file, it will usually open up on the python 2.7 IDE. How I solved this issue, was when I choose to run my code on python 3.3, I open up python 3.3 IDLE(Python GUI), select file, open my file with the IDLE and save it. Then when I run my code, it runs to the IDLE that I currently opened it with. It works vice versa with 2.7. | 8 | 234 | 0 | 0 | I do most of my programming in Python 3.x on Windows 7, but now I need to use the Python Imaging Library (PIL), ImageMagick, and wxPython, all of which require Python 2.x.
Can I have both Python 2.x and Python 3.x installed in Windows 7? When I run a script, how would I "choose" which version of Python should run it? Will the aforementioned programs be able to handle multiple versions of Python installed at once? I have searched for hours and hours for how to do this to no avail.
Thanks. | How to install both Python 2.x and Python 3.x in Windows | 0 | -0.010526 | 1 | 0 | 0 | 242,246 |
3,809,314 | 2010-09-28T02:40:00.000 | 0 | 0 | 1 | 0 | 0 | python,windows,compatibility,backwards-compatibility,build-environment | 0 | 17,660,471 | 0 | 19 | 0 | false | 0 | 0 | Install the one you use most (3.3 in my case) over the top of the other. That'll force IDLE to use the one you want.
Alternatively (from the python3.3 README):
Installing multiple versions
On Unix and Mac systems if you intend to install multiple versions of Python
using the same installation prefix (--prefix argument to the configure script)
you must take care that your primary python executable is not overwritten by the
installation of a different version. All files and directories installed using
"make altinstall" contain the major and minor version and can thus live
side-by-side. "make install" also creates ${prefix}/bin/python3 which refers to
${prefix}/bin/pythonX.Y. If you intend to install multiple versions using the
same prefix you must decide which version (if any) is your "primary" version.
Install that version using "make install". Install all other versions using
"make altinstall".
For example, if you want to install Python 2.6, 2.7 and 3.3 with 2.7 being the
primary version, you would execute "make install" in your 2.7 build directory
and "make altinstall" in the others. | 8 | 234 | 0 | 0 | I do most of my programming in Python 3.x on Windows 7, but now I need to use the Python Imaging Library (PIL), ImageMagick, and wxPython, all of which require Python 2.x.
Can I have both Python 2.x and Python 3.x installed in Windows 7? When I run a script, how would I "choose" which version of Python should run it? Will the aforementioned programs be able to handle multiple versions of Python installed at once? I have searched for hours and hours for how to do this to no avail.
Thanks. | How to install both Python 2.x and Python 3.x in Windows | 0 | 0 | 1 | 0 | 0 | 242,246 |
3,811,197 | 2010-09-28T09:04:00.000 | 1 | 1 | 0 | 1 | 0 | python,file-permissions | 0 | 3,811,219 | 0 | 4 | 0 | false | 0 | 0 | Start your program with a user that is allowed to write there. For example login to root first (su) or run the script with sudo myscript.py. | 1 | 6 | 0 | 0 | I m using shutil.copy from python to copy a list of files. But when i copy the files to /usr/lib/ location, i m getting permission denied as i need to be an administrator to do that.
So How could i copy files with admin permission or
how could i get the admin password from the user to copy the files?
Ideas would be appreciated | Getting admin password while copy file using shutil.copy? | 0 | 0.049958 | 1 | 0 | 0 | 7,772 |
3,814,365 | 2010-09-28T15:28:00.000 | 1 | 0 | 0 | 0 | 1 | python,xml.etree | 0 | 3,814,788 | 0 | 1 | 0 | true | 0 | 0 | register_namespace was only introduced in lxml 2.3 (still beta)
I believe you can provide an nsmap parameter (dictionary with prefix-uri mappings) when creating an element, but I don't think you can change it for an existing element. (there is an .nsmap property on the element, but changing that doesn't seem to work. There is also a .prefix property on the element, but that's read-only) | 1 | 3 | 0 | 0 | I wish to set the namespace prefix in xml.etree. I found register_namespace(prefix, url) on the Web but this threw "unknown attribute". I have also tried nsmap=NSMAP but this also fails. I'd be grateful for example syntax that shows how to add specified namespace prefixes | how to set namespace prefixes in xml.etree | 0 | 1.2 | 1 | 0 | 1 | 1,128 |
3,821,636 | 2010-09-29T12:41:00.000 | 2 | 0 | 0 | 1 | 0 | python,google-app-engine | 0 | 3,823,052 | 0 | 1 | 0 | true | 1 | 0 | I've solved this in the past by keeping the status for the tasks in memcached, and polling (via Ajax) to determine when the tasks are finished.
If you go this way, it's best if you can always "manually" determine the status of the tasks without looking in memcached, since there's always the (slim) chance that memcache will go down or will get cleared or something as a task is running. | 1 | 1 | 0 | 0 | I need to import some data to show it for user but page execution time exceeds 30 second limit. So I decided to split my big code into several tasks and try Task Queues. I add about 10-20 tasks to queue and app engine executes tasks in parallel while user is waiting for data. How can I determine that my tasks are completed to show user data ASAP? Can I somehow iterate over active tasks? | Python App Engine: Task Queues | 0 | 1.2 | 1 | 0 | 0 | 284 |
3,822,857 | 2010-09-29T14:55:00.000 | 1 | 0 | 0 | 0 | 0 | python,django-admin,customization | 0 | 3,831,573 | 0 | 2 | 0 | false | 1 | 0 | If I were you (and I am), I would stop trying to integrate this functionality with the Django admin site. Speaking from experience, you'll find that what you're trying to do is much easier to implement as regular views. Sure, it isn't be as pretty, but something that works beats something that's pretty but doesn't work, right? | 1 | 0 | 0 | 0 | I am trying to create a Django admin filter that will get random groups of users. At this point, I have two problems:
Applying a custom filter to the User model, and
Displaying a random set of users.
On #1, I've tried using User.username.random_filter = True, but it comes back with an AttributeError saying that User has no attribute username.
On #2, I know I can get 50 random users with User.objects.order_by('?')[:50], but I have not been able to figure out how to get the result of such a query to show up in the admin listing. As far as I can tell, the listing is generated by the URL's GET request, but I've not had any luck ordering with it.
Any suggestions? | Django randomly order users in admin | 0 | 0.099668 | 1 | 0 | 0 | 235 |
3,823,420 | 2010-09-29T15:57:00.000 | 1 | 0 | 0 | 0 | 0 | python,network-protocols | 0 | 3,824,612 | 0 | 2 | 0 | false | 0 | 0 | It wasn't obvious from your question but if getting answers back synchronously doesn't matter to you (i.e., you are just asking for work to be performed) you might want to consider just using a job queue. It's generally the easiest way to communicate between hosts. If you don't mind depending on AWS using SQS is super simple. If you can't depend on AWS then you might want to try something like RabbitMQ. Many times problems that we think need to be communicated synchronously are really just queues in disguise. | 1 | 0 | 0 | 0 | The situation is that I have a small datacenter, with each server running python instances. It's not your usual distributed worker setup, as each server has a specific role with an appropriate long-running process.
I'm looking for good ways to implement the the cross-server communication. REST seems like overkill. XML-RPC seems nice, but I haven't played with it yet. What other libraries should I be looking at to get this done?
Requirements:
Computation servers crunch numbers in the background. Other servers would like to occasionally ask them for values, based upon their calculation sets. I know this seems pretty well aligned with a REST mentality, but I'm curious about other options. | What are good specs/libraries for closed network communication in python? | 0 | 0.099668 | 1 | 0 | 1 | 196 |
3,824,923 | 2010-09-29T18:59:00.000 | 13 | 0 | 0 | 0 | 0 | python,apache,logging,mod-wsgi | 0 | 3,825,257 | 0 | 1 | 0 | true | 1 | 0 | Mostly, we use logging and write to sys.stderr. That seems to write to the Apache error_log. | 1 | 12 | 0 | 0 | I have a Django project where I have been logging to a file using the standard library logging module. For a variety of reasons I would like to change it so that it writes to the Apache log files. I've seen quite a bit of discussion of how to do this with mod_python, but not mod_wsgi. How do I do this for a project running under mod_wsgi? | How do I write to the apache log files when using mod_wsgi | 0 | 1.2 | 1 | 0 | 0 | 3,241 |
3,829,405 | 2010-09-30T09:40:00.000 | 0 | 0 | 0 | 0 | 1 | python,code-generation,web-crawler,robot | 0 | 3,829,743 | 0 | 1 | 0 | true | 1 | 0 | You need to separate out the idea of what code to generate from the events triggering generation.
What code is generated is governed by the combined set of all the checkboxes that are checked.
Triggering code generation occurs each time any of them are changed. You need to regenerate everything at that time.
In detail:
Check box 1 -- triggers generation, just code for snippet 1 included
Check box 2 -- triggers generation, code for snippets 1 & 2 included
Check box 3 -- triggers generation, code for snippets 1, 2 & 3 included
Uncheck box 2 -- triggers generation, code for snippets 1 & 3 included | 1 | 1 | 0 | 0 | I want to write a web-based code generator for a Python crawler. Its aim is to automatically generate code so a developer doesn't need to write it, but I've run into this problem: in one of my project's webpages, there are some checkboxes, buttons, etc. Each of them generates some Python code and writes it to a common textarea. However, when I uncheck boxes I can't figure out how to remove the corresponding code from the textarea, because it's all been mixed together. For example:
Check box 1 -- it writes code snippet 1 to the textarea
Check box 2 -- it writes code snippet 2 to the textarea
Check box 3 -- it writes code snippet 3 to the textarea
Uncheck box 2 -- it needs to somehow remove code snippet 2 from the text area, but leave behind code snippets 1 and 3
Is there some way to fix this problem, or any better solution for the whole code generator project? | Problem with web code generator designer | 0 | 1.2 | 1 | 0 | 0 | 82 |
3,836,620 | 2010-10-01T04:51:00.000 | 0 | 0 | 0 | 0 | 0 | python,continuous | 0 | 3,836,650 | 0 | 3 | 0 | false | 0 | 0 | If you really wanted to (and wanted to waste a lot of resources), you could cut your loop into 200 ms chunks. So sleep 200 ms, check input, repeat until five minutes elapse, and then check your inbox. I wouldn't recommend it, though.
While it's sleeping, though, the process is blocked and won't receive input until the sleep ends.
Oh, as an added note, if you hit the key while it's sleeping, it should still go into the buffer, so it'll get pulled out when the sleep ends and input is finally read, IIRC. | 1 | 4 | 0 | 0 | I have a script that runs continuously when invoked and every 5 minutes checks my gmail inbox. To get it to run every 5 minutes I am using the time.sleep() function. However I would like user to end the script anytime my pressing q, which it seems cant be done when using time.sleep(). Any suggestions on how i can do this?
Ali | Continous loop and exiting in python | 0 | 0 | 1 | 0 | 1 | 5,470 |
3,839,216 | 2010-10-01T12:41:00.000 | 0 | 0 | 0 | 0 | 0 | javascript,python,html,css,user-interface | 0 | 3,839,449 | 0 | 10 | 0 | true | 1 | 0 | update: This is an old answer, nowadays you want to go with an embedded browser in your app (*webkit projects etc.), but at the time of writing, no such technology existed. The answer is still valid if you don't want to add quite a few megabytes to your packaged app though.
Find a lightweight server, or better - embed one in Your application. That's it.
Java has classes for serving http. Python does it well also.
See how mercurial's hg serve works. [python]
I once did a tiny app that served aspell spellcheck via http on localhost in java with the httprequest class. [worked on win and linux]
Create Your application as a server that outputs some html and uses POST to do actions. Do the interface thing in HTML+CSS+JS. Nice and easy.
After running point the user to localhost:somesillyport or trigger opening localhost:somesillyport in a browser. | 1 | 11 | 0 | 0 | Different languages have different GUI toolkits, but it looks very difficult to achieve attractive user interfaces as good as we can using HTML and CSS with less effort.
I don't do my application in javascript as I doubt if it has all the required libraries and I want to do it in python.
How do I use rendering engines like gecko, webkit etc in python? Which one will be more suited to work with python?.Is there any 'only html/css' rendering engine without javascript?
Will it be easy to write event handlers for DOM events and manipulate DOM in python? | how to write a desktop application which uses HTML and CSS for user interface and python/perl/c++/java for the processing? | 0 | 1.2 | 1 | 0 | 0 | 4,636 |
3,844,158 | 2010-10-02T02:49:00.000 | 8 | 1 | 1 | 0 | 0 | python,oop | 0 | 3,844,175 | 0 | 2 | 0 | true | 0 | 0 | What are these kinda classes classified under OOdesign? Can I do it in a more elegant way?
You do have better alternatives, IMHO.
I use a class that has just named constants , this class is used directly other classes to get values of constants in it.I dont instantiate the class.
For e.g. in this case you don't necessarily need a class. You can have a settings module that defines the various "constants". I put constants in quotes because there are no constants in Python the way there are in say, Java.
(2) I use a class with full of static methods, this class is basically used by other classes as a holder of methods that are used by them. So again i dont instantiate the class.
Again, no need for a class. You can have one or more modules that contain these methods or rather, functions. They can be logically grouped as you see fit.
I'd like to add a note that you don't have to stick to (Java style?) "classes only" approach (for lack of a better phrase). Rather try to write code that doesn't go against the grain of the language. In Python's case I'd argue that such classes as you described above are best avoided. They seem to me like a carry over from Java. | 1 | 2 | 0 | 0 | I just want to know how I can call certian classes in design pattern here, like which type are they classified in OO design
(1) I use a class that has just named constants , this class is used directly other classes to get values of constants in it.I dont instantiate the class.
(2) I use a class with full of static methods, this class is basically used by other classes as a holder of methods that are used by them. So again i dont instantiate the class.
What are these kinda classes classified under OOdesign?
Can I do it in a more elegant way? | Static or constant or what are they? | 0 | 1.2 | 1 | 0 | 0 | 705 |
3,853,038 | 2010-10-04T05:22:00.000 | 0 | 0 | 0 | 1 | 0 | python,macos,command-line | 0 | 3,853,095 | 0 | 2 | 0 | false | 0 | 0 | have you tried using the nohup? lets say you have a launch script to start your program:
launch.sh:
nohup your_program &
exit | 1 | 2 | 0 | 0 | For great help from stackoverflow, the development for the Mac version of my program is done.
Now I need to deploy my program, and I was wondering if there is any way to "hide" my running Python code (it also runs .so library and it seems it makes a dock item to appear).
The program is supposed to be running in the background and it would be great if I can hide any terminal or dock items. In Windows or linux, it was easy, but I am still not that used to Mac and could not figure out how to do this.
Thank you,
Joon | Run a python script and a compiled c code without terminal or dock item in Mac OS X | 1 | 0 | 1 | 0 | 0 | 1,064 |
3,867,377 | 2010-10-05T20:17:00.000 | 3 | 1 | 1 | 0 | 0 | ironpython | 0 | 3,869,625 | 0 | 1 | 0 | true | 0 | 0 | It's interesting, there's actually no support for this at all right now. For the most part this has been used to implement built-in modules that exist in CPython and there's simply been no need for submodules yet. You could have a nested static class in the class used for the module but it wouldn't import as a module - it'd show up as a type object in Python. | 1 | 2 | 0 | 0 | While I'm familiar with making .net assemblies with the PythonModule assembly attribute, I'm a little curious as to how you could make submodules. Would this be a class within a class? i.e: if I have a class defined as an IronPython module such as:
[assembly: PythonModule(mymodule),typeof(namespace.mymodule)]
How could I define a submodule within mymodule, so that from python I could do:
import mymodule.submodule
Thanks in advance! | submodules in ironpython | 0 | 1.2 | 1 | 0 | 0 | 183 |
3,867,500 | 2010-10-05T20:34:00.000 | 1 | 0 | 0 | 1 | 0 | python,user-interface,wxpython,wxwidgets,command-line-interface | 0 | 3,867,843 | 0 | 2 | 0 | false | 0 | 0 | If you can call your data model's methods from your GUI and they don't depend on anything in the GUI, then yes, you should be able to call those same methods from another GUI, be it CLI, pyGTK or whatever. | 1 | 0 | 0 | 0 | HI, guys. I am developing a GUI to configure and call several external programs with Python and I use wxPython for the GUI toolkits. Basically, instead of typing commands and parameters in each shell for each application (one application via one shell), the GUI is visualizing these parameters and call them as subprocesses. I have built the data model and the relevant view/gui controls (mainly by using the observer pattern or try to separate model with the gui widgets), and it is OK.
Now there is a request from my colleagues and many other people (even including myself), is it possible to have a command line interface for the subprocesses, or even for the whole configuration GUI, based on the data model I already have? This is due to the fact that many people prefer CLI, CLI is better in reliability, and also needs of programmer debugging and interfacing.
As I am rather new to developing a CLI, I really need some help from you. I appreciate any advice and information from you.
to be more specific,
If I completely forget about the data model built for GUI, start from scratch. Is there some good materials or samples to have a reference?
If I still want to utilize the data model built for GUI, is it possible? If possible, what shall I do and any samples to follow? Do I need to refactor the data model?
Is it possible to have the CLI and GUI at the same time? I mean, can I take the CLI as another view of the data model? Or there is other right approach?
Thank you very much for your help!! | how to make a Command Line Interface from a given data model used for GUI | 1 | 0.099668 | 1 | 0 | 0 | 440 |
3,873,212 | 2010-10-06T13:56:00.000 | 1 | 0 | 1 | 0 | 0 | .net,vb.net,ironpython | 0 | 3,873,713 | 0 | 1 | 0 | true | 0 | 0 | The full name for the method is Microsoft.VisualBasic.DateAndTime.Year(DateTime). This is a compat function. Since you need to pass a DateTime argument anyway, you might as well use its Year property.
Albeit that the VB version can be different because it uses the current culture calendar's GetYear() method. In other words, in Israel your program might get the year since the destruction of the temple in Jerusalem (I think). Not sure if that should be intentional in your case. | 1 | 0 | 0 | 0 | Since it's possible using the IsNumeric() and others VB.NET functions from IronPython by importing Microsoft.VisualBasic and using it as an object method, is it possible somehow to use the Year() VB.NET function from IronPython? | using the VB.NET Year function from IronPython | 1 | 1.2 | 1 | 0 | 0 | 163 |
3,874,837 | 2010-10-06T16:37:00.000 | 0 | 0 | 1 | 0 | 0 | python,compression,gzip,tar | 0 | 3,874,884 | 0 | 4 | 0 | false | 0 | 0 | As larsmans says, gzip compression is not used for directories, only single files. The usual way of doing things with linux is to put the directory in a tarball first and then compress it. | 1 | 12 | 0 | 0 | I'm creating Python software that compresses files/folders... How would I create a section of the code that asks for the user input of the folder location and then compresses it. I currently have the code for a single file but not a folder full of files. Please explain in detail how to do this. | How do I compress a folder with the Python GZip module? | 0 | 0 | 1 | 0 | 0 | 24,451 |
3,877,631 | 2010-10-06T23:28:00.000 | 0 | 1 | 0 | 0 | 1 | python,google-app-engine,ip-address | 0 | 3,877,766 | 1 | 1 | 1 | true | 1 | 0 | I believe that I have figured out the reason for seeing so many warnings from google server IP addresses. It seems that immediately after a new user registers, the google crawlers are going to the same (registration) webpage (which I send information to as a GET instead of a POST for reasons which I will not get into). Of course, since many users are registering, but there are only a few crawler computers that are checking periodic updates to my website, I am triggering warning messages that a particular (google) IP is accessing a registration area repeatedly. | 1 | 0 | 0 | 0 | In order to make the registration process on my website easy, I allow users to enter their email address which I will send a verification code to or alternatively they can solve a captcha.
The problem is that in order to prevent robots from registering accounts (with fake emails) I limit the number of registrations allowed per IP address and if this limit is exceeded I trigger a warning in the logs.
However ... what seems to be happening is that I am using os.environ['REMOTE_ADDR'] to check the remote address -- but it seems that I am triggering warnings on addresses that are owned by Google (66.249.65.XXX). It is possible that this is happening only after I change the version (but not confirmed). Does anyone know how/why this might be happening? Shouldn't the REMOTE_ADDR return the address of the client computer (and hopefully in all cases it would do this)?
I am curious if there is some behind the scenes re-directions going on, and if this is a normal event or if it only happens when a new version is installed (perhaps when a new version is installed the original server then proxies the user to the new server, therefore creating the illusion that the IP address is an internal IP?) | Google App Engine (Python)- Strange behaviour of REMOTE_ADDR | 1 | 1.2 | 1 | 0 | 0 | 438 |
3,881,951 | 2010-10-07T13:10:00.000 | 0 | 0 | 0 | 0 | 0 | python | 0 | 3,882,193 | 0 | 2 | 0 | false | 0 | 0 | The IP addresses are assigned to your VPSes, no possibility to change them on the fly.
You have to open a SSH tunnel to or install a proxy on your VPSes.
I think a SSH tunnel would be the best way how to do it, and then use it as SOCKS5 proxy from Python. | 1 | 1 | 0 | 0 | I am running my code on multiple VPSes (with more than one IP, which are set up as aliases to the network interfaces) and I am trying to figure out a way such that my code acquires the IP addresses from the network interfaces on the fly and bind to it. Any ideas on how to do it in python without adding a 3rd party library ?
Edit I know about socket.gethostbyaddr(socket.gethostname()) and about the 3rd party package netifaces, but I am looking for something more elegant from the standard library ... and parsing the output of the ifconfig command is not something elegant :) | figuring out how to get all of the public ips of a machine | 0 | 0 | 1 | 0 | 1 | 118 |
3,883,497 | 2010-10-07T15:57:00.000 | 18 | 0 | 0 | 0 | 0 | python,django | 0 | 3,883,556 | 0 | 3 | 0 | true | 1 | 0 | Just run two instances of ./manage.py runserver. You can set a port by simply specifying it directly: ./manage.py runserver 8002 to listen on port 8002.
Edit I don't really understand why you want to do this. If you want two servers serving different parts of your site, then you have in effect two sites, which will need two separate settings.py and urls.py files. You'd then run one instance of runserver with each, passing the settings flag appropriately: ./manage.py runserver 8002 --settings=app1.settings | 2 | 8 | 0 | 0 | Could someone tell me how I can run Django on two ports simultaneously? The default Django configuration only listens on port 8000. I'd like to run another instance on port xxxx as well. I'd like to redirect all requests to this second port to a particular app in my Django application.
I need to accomplish this with the default Django installation and not by using a webserver like nginx, Apache, etc.
Thank you
Let's say I two applications in my Django application. Now i don't mean two separate Django applications but the separate folders inside the 'app' directory. Let's call this app1 and app2
I want all requests on port 8000 to go to app1 and all requests on port XXXX to go to app2
HTH. | Run Django on multiple ports | 0 | 1.2 | 1 | 0 | 0 | 14,240 |
3,883,497 | 2010-10-07T15:57:00.000 | 2 | 0 | 0 | 0 | 0 | python,django | 0 | 3,883,557 | 0 | 3 | 0 | false | 1 | 0 | The built-in web-server is intended for development only, so you should really be using apache or similar in an situation where you need to run on multiple ports.
On the other hand you should be able to start up multiple servers just by starting multiple instances of runserver. As long as you are using a separate database server I don't think that will have any extra problems. | 2 | 8 | 0 | 0 | Could someone tell me how I can run Django on two ports simultaneously? The default Django configuration only listens on port 8000. I'd like to run another instance on port xxxx as well. I'd like to redirect all requests to this second port to a particular app in my Django application.
I need to accomplish this with the default Django installation and not by using a webserver like nginx, Apache, etc.
Thank you
Let's say I two applications in my Django application. Now i don't mean two separate Django applications but the separate folders inside the 'app' directory. Let's call this app1 and app2
I want all requests on port 8000 to go to app1 and all requests on port XXXX to go to app2
HTH. | Run Django on multiple ports | 0 | 0.132549 | 1 | 0 | 0 | 14,240 |
3,883,619 | 2010-10-07T16:12:00.000 | 0 | 0 | 1 | 0 | 0 | python,django,shell,ipython | 0 | 34,309,424 | 0 | 5 | 0 | false | 1 | 0 | The easiest solution I've found is combination of shell_plus and iPython which automatically reloads functions.
pip install ipython
pip install django-extensions
add 'django_extensions' to your INSTALLED_APPS
python manage.py shell_plus | 1 | 6 | 0 | 0 | I work in the django IPython-shell, which can be started with manage.py shell.
When i load an extern function in the shell for testing, everything is alright. But when i make changes to the function, the shell still has the old version of the function. Even if i make a new import.
Does anyone know how to reload the actual version of the function?
Thanks in regards!
Edit: I use windows - if that makes a difference. | django, python: reload function in shell | 0 | 0 | 1 | 0 | 0 | 8,233 |
3,884,881 | 2010-10-07T18:53:00.000 | 0 | 0 | 1 | 1 | 1 | python,windows-xp | 0 | 3,884,931 | 0 | 3 | 0 | false | 0 | 0 | You need to map it as a drive. | 1 | 2 | 0 | 0 | How can I open a Python interpreter at a specific network path in Windows?
In the Explorer address bar the path is in UNC form: \\myhost\myshare\....
I can't work out how to change to this directory from the Windows command line, nor in what format I could pass it as an argument to os.chdir.
I'm running Python 2.5 on Windows XP. IDLE is installed.
Thanks! | How can I open a Python shell at a network path in Windows? | 0 | 0 | 1 | 0 | 0 | 2,258 |
3,885,160 | 2010-10-07T19:24:00.000 | 0 | 0 | 0 | 1 | 0 | python,linux,networking,ip-address | 0 | 3,885,255 | 0 | 2 | 0 | false | 0 | 0 | If the default gateway for the system is reliable, then grab that from the output from route -n the line that contains " UG " (note the spaces) will also contain the IP of the gateway and interface name of the active interface. | 1 | 1 | 0 | 0 | On my linux machine, 1 of 3 network interfaces may be actually connected to the internet. I need to get the IP address of the currently connected interface, keeping in mind that my other 2 interfaces may be assigned IP addresses, just not be connected.
I can just ping a website through each of my interfaces to determine which one has connectivity, but I'd like to get this faster than waiting for a ping time out. And I'd like to not have to rely on an external website being up.
Update:
All my interfaces may have ip addresses and gateways. This is for an embedded device. So we allow the user to choose between say eth0 and eth1. But if there's no connection on the interface that the user tells us to use, we fall back to say eth2 which (in theory) will always work.
So what I need to do is first check if the user's selection is connected and if so return that IP. Otherwise I need to get the ip of eth2. I can get the IPs of the interfaces just fine, it's just determining which one is actually connected. | Determine IP address of CONNECTED interface (linux) in python | 0 | 0 | 1 | 0 | 1 | 2,443 |
3,886,402 | 2010-10-07T22:38:00.000 | 7 | 0 | 1 | 0 | 0 | python,floating-point,decimal | 0 | 66,605,212 | 0 | 36 | 0 | false | 0 | 0 | To make it work with both positive and negative numbers:
try abs(x)%1. For negative numbers, without with abs, it will go wrong.
5.55 % 1
output 0.5499999999999998
-5.55 % 1
output 0.4500000000000002 | 1 | 164 | 0 | 0 | How do I get the numbers after a decimal point?
For example, if I have 5.55, how do i get .55? | How to get numbers after decimal point? | 0 | 1 | 1 | 0 | 0 | 285,621 |
3,886,500 | 2010-10-07T22:56:00.000 | 0 | 0 | 0 | 0 | 0 | python,multithreading,pyqt,copy-paste | 0 | 3,886,510 | 0 | 1 | 0 | false | 0 | 1 | In Qt you would overload the OnClose method for the widget/frame or hook the lastwindowsdclosed signal to do whatever you need to shut down the app - don't know if it's diiferent from python | 1 | 0 | 0 | 0 | I have a programs that runs several threads (on a while loop until
Ctrl C is pressed). The app also has a GUI that I developed in PyQt. However, I am facing the following problem:
If I press Ctrl C on the console, and then close the GUI, the program exits fine. However, if I close the GUI first, the other threads won't stop and the program keeps running after Ctrl C. Anyone knows how I could address this problem? | PyQT4 and Ctrl C | 0 | 0 | 1 | 0 | 0 | 722 |
3,890,321 | 2010-10-08T12:11:00.000 | 8 | 0 | 1 | 0 | 0 | python,grammar | 0 | 3,890,344 | 0 | 2 | 0 | true | 0 | 0 | Grammars are generally of the same form: Backus-Naur Form (BNF) is typical.
Lexer/parsers can take very different forms.
The lexer breaks up the input file into tokens. The parser uses the grammar to see if the stream of tokens is "valid" according to its rules.
Usually the outcome is an abstract syntax tree (AST) that can then be used to generate whatever you want, such as byte code or assembly. | 1 | 4 | 0 | 0 | I wonder how is generated the grammar of the Python language and how it is understood by the interpreter.
In python, the file graminit.c seems to implement the grammar, but i don't clearly understand it.
More broadly, what are the different ways to generate a grammar and are there differences between how the grammar is implemented in languages such as Perl, Python or Lua. | How is generated the python grammar and how the interpreter understand it | 1 | 1.2 | 1 | 0 | 0 | 841 |
3,890,390 | 2010-10-08T12:22:00.000 | 7 | 0 | 1 | 0 | 0 | javascript,python,sockets,encoding | 0 | 3,890,407 | 0 | 2 | 1 | false | 1 | 0 | JSON is definitely the way to go. It has a very small overhead and is capable of storing almost any kind of data. I am not a python expert, but i am sure that there is some kind of en/decoder available. | 1 | 1 | 0 | 1 | OK so im using websockets to let javascript talk to python and that works very well BUT the data i need to send often has several parts like an array, (username,time,text) but how could i send it ? I originally though to encode each one in base64 or urlencode then use a character like | which those encoding methods will never use and then split the information. Unfortunately i cant find a method which both python and javascript can both do.
So the question, is there a encoding method which bath can do OR is there a different better way i can send the data because i havent really done anything like this before. (I have but AJAX requests and i send that data URL encoded). Also im not sending miles of text, about 100bytes at a time if that.
thankyou !
edit
Most comments point to JSON,so, Whats the best convert to use for javascript because javascript stupidly cant convert string to JSON,or the other way round.
Finished
Well jaascript does have a native way to convert javascript to string, its just hidden form the world. JSON.stringify(obj, [replacer], [space]) to convert it to a string and JSON.parse(string, [reviver]) to convert it back | Python to javascript communication | 0 | 1 | 1 | 0 | 1 | 1,908 |
3,897,140 | 2010-10-09T17:31:00.000 | 0 | 1 | 0 | 1 | 1 | python,apache | 1 | 3,898,807 | 0 | 2 | 0 | false | 1 | 0 | You'd need to show your apache configuration to say for certain, but it seems that Apache isn't actually using mod_cgi to serve the index.cgi script. In your configuration there should be something like 'LoadModule mod_cgi'. It should be uncommented (i.e., it shouldn't have a '#' at the beginning of the line).
If you want to test this, then write a 'Hello World' cgi script and put it (temporarily) in place of index.cgi and see if you can get that to run. Let us know the results. | 2 | 0 | 0 | 0 | I have a CGI script (pwyky) that I called index.cgi, put in directory wiki/, and setup Apache to call localhost/wiki/index.cgi when I access localhost/wiki.
I'm getting errors when I'm trying to use this application -- it creates a page with links like "http://localhost/wiki/@edit/index", but when I click that link, Apace is trying to serve "wiki/@edit/index" as a file. I suspect that I need to get Apache to pass /@edit/index into index.cgi.
In particular, looking through index.cgi, its looking for strings like "@edit" in REQUEST_URI environment variable.
Any idea how to fix this? | URL rewriting question | 0 | 0 | 1 | 0 | 0 | 762 |
3,897,140 | 2010-10-09T17:31:00.000 | 0 | 1 | 0 | 1 | 1 | python,apache | 1 | 3,908,016 | 0 | 2 | 0 | true | 1 | 0 | I found the problem, it turned out this is done through RewriteEngine. Pwyky puts .htaccess file in the directory with all the settings for RewriteEngine, but because AllowOverride is "None" by default on MacOS, they were ignored. The solution was to change all "AllowOverride" directives to "All" | 2 | 0 | 0 | 0 | I have a CGI script (pwyky) that I called index.cgi, put in directory wiki/, and setup Apache to call localhost/wiki/index.cgi when I access localhost/wiki.
I'm getting errors when I'm trying to use this application -- it creates a page with links like "http://localhost/wiki/@edit/index", but when I click that link, Apace is trying to serve "wiki/@edit/index" as a file. I suspect that I need to get Apache to pass /@edit/index into index.cgi.
In particular, looking through index.cgi, its looking for strings like "@edit" in REQUEST_URI environment variable.
Any idea how to fix this? | URL rewriting question | 0 | 1.2 | 1 | 0 | 0 | 762 |
3,898,988 | 2010-10-10T04:11:00.000 | 1 | 0 | 0 | 0 | 0 | python,wxpython,frame,send | 0 | 3,906,746 | 0 | 2 | 0 | false | 0 | 1 | I'd definitely use PubSub as it's probably the cleanest way I can think of to do it. You can also do it with wx.PostEvent or use a modal frame. | 1 | 1 | 0 | 0 | I'm writing a small app which has 2 separate frames.
The first frame is like a video player controller. It has Play/Stop/Pause buttons etc. It's named controller.py.
The second frame contains OpenGL rendering and many things inside it, but everything is wrapped inside a Frame() class as the above. It's named model.py.
I'm up to the final part where I have to "join" these two together.
Does anyone know how to control a frame (model.py) from another frame (controller.py)?
I would like to do something like a movie player when you clicks play it pops up a new window and play until the stop button is clicked.
If you know how, please let me know. (Just tell me in general no need to specific). | How to control a frame from another frame? | 0 | 0.099668 | 1 | 0 | 0 | 669 |
3,900,403 | 2010-10-10T13:03:00.000 | 1 | 0 | 0 | 0 | 0 | python,sockets,serial-port | 0 | 3,900,446 | 0 | 2 | 0 | false | 0 | 0 | The simplest way is to simply accept a connection, handle the request, and close the connection. This way, your program handles only one request at a time.
An alternative is to use locking or semaphores, to prevent multiple clients accessing the RS232 port simultaneously. | 1 | 1 | 0 | 0 | I need to expose an RS232 connection to clients via a network socket. I plan to write in python a TCP socket server which will listen on some port, allow client to connect and handle outgoing and manage and control requests and replies to from the R2232 port.
My question is, how do I synchronize the clients, each client will send some string to the serial port and after the reply is sent back I need to return that client the result. Only then do I need to process the next request.
How to I synchronize access to the serial port ? | Writing a TCP to RS232 driver | 0 | 0.099668 | 1 | 0 | 1 | 1,048 |
3,902,996 | 2010-10-11T01:28:00.000 | -2 | 0 | 1 | 0 | 0 | python,debugging,ide | 0 | 3,903,016 | 0 | 6 | 0 | false | 0 | 0 | To start coding in a file, just open a new file and start typing. | 4 | 3 | 0 | 0 | This obviously an extremely novice question, but I've installed Python 2.7 and started reading the manual. However I looked and looked, and couldn't understand how to start programming a file rather than writing in interactive mode. One book that was online suggested quit(), which surprise -- quit the program.
Should coding be done in a different program? I'm using IDLE (Python GUI). Can coding not be done within that program? | How to get out of interactive mode in Python | 0 | -0.066568 | 1 | 0 | 0 | 7,387 |
3,902,996 | 2010-10-11T01:28:00.000 | 0 | 0 | 1 | 0 | 0 | python,debugging,ide | 0 | 16,851,751 | 0 | 6 | 0 | false | 0 | 0 | use new window tool in the file icon,in the python idle itself to write a program | 4 | 3 | 0 | 0 | This obviously an extremely novice question, but I've installed Python 2.7 and started reading the manual. However I looked and looked, and couldn't understand how to start programming a file rather than writing in interactive mode. One book that was online suggested quit(), which surprise -- quit the program.
Should coding be done in a different program? I'm using IDLE (Python GUI). Can coding not be done within that program? | How to get out of interactive mode in Python | 0 | 0 | 1 | 0 | 0 | 7,387 |
3,902,996 | 2010-10-11T01:28:00.000 | 0 | 0 | 1 | 0 | 0 | python,debugging,ide | 0 | 3,903,066 | 0 | 6 | 0 | false | 0 | 0 | Push new to start making your own script file. Then when you are ready to test click run and then you can watch the results in the interactive mode, and even try new things as if you were adding code to the end of your script file, its a very useful app for debugging, testing and trying new things.
Also in the options you can change the way python opens your scripts when you click edit from windows, you can set it so that it opens the interactive shell or just the editor. | 4 | 3 | 0 | 0 | This obviously an extremely novice question, but I've installed Python 2.7 and started reading the manual. However I looked and looked, and couldn't understand how to start programming a file rather than writing in interactive mode. One book that was online suggested quit(), which surprise -- quit the program.
Should coding be done in a different program? I'm using IDLE (Python GUI). Can coding not be done within that program? | How to get out of interactive mode in Python | 0 | 0 | 1 | 0 | 0 | 7,387 |
3,902,996 | 2010-10-11T01:28:00.000 | 2 | 0 | 1 | 0 | 0 | python,debugging,ide | 0 | 3,903,006 | 0 | 6 | 0 | false | 0 | 0 | Yes, coding should be done in a different program. The interactive shell is very useful but it's not an editor. | 4 | 3 | 0 | 0 | This obviously an extremely novice question, but I've installed Python 2.7 and started reading the manual. However I looked and looked, and couldn't understand how to start programming a file rather than writing in interactive mode. One book that was online suggested quit(), which surprise -- quit the program.
Should coding be done in a different program? I'm using IDLE (Python GUI). Can coding not be done within that program? | How to get out of interactive mode in Python | 0 | 0.066568 | 1 | 0 | 0 | 7,387 |
3,905,791 | 2010-10-11T11:33:00.000 | 1 | 0 | 0 | 1 | 0 | python,twisted,factory | 0 | 3,906,174 | 0 | 1 | 0 | false | 1 | 0 | No. Write a class that does the interaction with one user. In connectionMade you check if a instance of this class already exists, if not you make a new one and store it on the factory, ie in a { addr : handler } dict. If the connection exists alreay you get the old handler from the factory. | 1 | 0 | 0 | 0 | Hey, I got a ReconnectingClientFactory and I wonder if I can somehow define protocol-instance-based connectionMade/connectionLost callbacks so that i can use the factory to connect to different hosts ans distinguish between each connection.
Thanks in advance. | Twisted factory protocol instance based callback | 0 | 0.197375 | 1 | 0 | 0 | 499 |
3,912,579 | 2010-10-12T07:53:00.000 | 2 | 0 | 0 | 0 | 0 | python,django,installation | 0 | 3,912,677 | 0 | 1 | 0 | true | 1 | 0 | It is very likely that the py extension is linked with the editor rather than the Python interpreter.
Right-click on a py file and click "Open with" then select the default program and choose 'C:...\Python2x\python.exe'
That should fix the pb | 1 | 1 | 0 | 0 | I've got an issue when installing Django.
The official guide says open cmd with administrator privileges and run "setup.py install"
I did this but then the system default python editor came out, I don't know how to do anymore, please help me~ | Issue happens when installing Django on Windows 7 | 0 | 1.2 | 1 | 0 | 0 | 494 |
3,913,217 | 2010-10-12T09:30:00.000 | -1 | 1 | 1 | 0 | 0 | python,programming-languages,namespaces | 0 | 3,913,281 | 0 | 6 | 0 | false | 0 | 0 | If you make a big program with someone else, you could write your own part of the program as you want. All variables in the file will be private, there will be no collisions.
When you write PHP programs, it is easy to rewrite global variables by mistake. In python you can import other modules variables if you want, and they will be "global" on your module.
You could think one file one object in Python. When you write PHP programs you can achieve the same by writing classes with instance variables. | 2 | 47 | 0 | 0 | I have just started learning Python & have come across "namespaces" concept in Python. While I got the jist of what it is, but am unable to appreciate the gravity of this concept.
Some browsing on the net revealed that one of the reasons going against PHP is that it has no native support for namespaces.
Could someone explain how to use namespaces & how this feature makes programming better (not just in Python, as I assume namespaces in not a concept limited to a particular language).
I am predominantly coming from Java and C programming backgrounds. | What are Python namespaces all about | 0 | -0.033321 | 1 | 0 | 0 | 29,735 |
3,913,217 | 2010-10-12T09:30:00.000 | 49 | 1 | 1 | 0 | 0 | python,programming-languages,namespaces | 0 | 3,913,488 | 0 | 6 | 0 | true | 0 | 0 | Namespace is a way to implement scope.
In Java (or C) the compiler determines where a variable is visible through static scope analysis.
In C, scope is either the body of a function or it's global or it's external. The compiler reasons this out for you and resolves each variable name based on scope rules. External names are resolved by the linker after all the modules are compiled.
In Java, scope is the body of a method function, or all the methods of a class. Some class names have a module-level scope, also. Again, the compiler figures this out at compile time and resolves each name based on the scope rules.
In Python, each package, module, class, function and method function owns a "namespace" in which variable names are resolved. Plus there's a global namespace that's used if the name isn't in the local namespace.
Each variable name is checked in the local namespace (the body of the function, the module, etc.), and then checked in the global namespace.
Variables are generally created only in a local namespace. The global and nonlocal statements can create variables in other than the local namespace.
When a function, method function, module or package is evaluated (that is, starts execution) a namespace is created. Think of it as an "evaluation context". When a function or method function, etc., finishes execution, the namespace is dropped. The variables are dropped. The objects may be dropped, also. | 2 | 47 | 0 | 0 | I have just started learning Python & have come across "namespaces" concept in Python. While I got the jist of what it is, but am unable to appreciate the gravity of this concept.
Some browsing on the net revealed that one of the reasons going against PHP is that it has no native support for namespaces.
Could someone explain how to use namespaces & how this feature makes programming better (not just in Python, as I assume namespaces in not a concept limited to a particular language).
I am predominantly coming from Java and C programming backgrounds. | What are Python namespaces all about | 0 | 1.2 | 1 | 0 | 0 | 29,735 |
3,914,725 | 2010-10-12T12:35:00.000 | 5 | 0 | 1 | 0 | 0 | python,number-formatting | 0 | 3,914,765 | 0 | 8 | 0 | false | 0 | 0 | x = round(293.4662543, 2) | 1 | 32 | 0 | 0 | How to shorten the float result I got? I only need 2 digits after the dot. Sorry I really don't know how to explain this better in English...
Thanks | How to turn a float number like 293.4662543 into 293.47 in python? | 0 | 0.124353 | 1 | 0 | 0 | 103,306 |
3,916,553 | 2010-10-12T15:50:00.000 | -5 | 1 | 0 | 0 | 1 | python,garbage-collection,root,performance | 0 | 3,919,321 | 0 | 3 | 1 | false | 0 | 1 | If your problem really is the garbage collection, try explicitly freeing your objects when you're done with them using del().
In general, this doesn't sound like a garbage collection problem, unless we're talking about terabytes of memory.
I agree with S.Lott... profile your app, then bring code snippets and the results of that back and we can be much more helpful. | 1 | 18 | 0 | 0 | I have a problem with my python application, and I think it's related to the python garbage collection, even if I'm not sure...
The problem is that my application takes a lot of time to exit and to switch to one function to the next one.
In my application I handle very large dictionaries, containing thousands of large objects which are instantiated from wrapped C++ classes.
I put some timestamp outputs in my program, and I saw that at the end of each function, when objects created inside the function should go out of scope, a lot of time is spent by the interpreter before calling the next function. And I observe the same problem at the end of the application, when the program should exit: a lot of time (~ hours!) is spent between the last timestamp on screen and the appearance of the fresh prompt.
The memory usage is stable, so I don't really have memory leaks.
Any suggestions?
Can be the garbage collection of thousands of large C++ objects that slow?
Is there a method to speed up that?
UPDATE:
Thanks a lot for all your answers, you gave me a lot of hints to debug my code :-)
I use Python 2.6.5 on Scientific Linux 5, a customized distribution based on Red Hat Enterprise 5.
And actually I'm not using SWIG to get Python bindings for our C++ code, but the Reflex/PyROOT framework. I know, it's not very known outside particle physics (but still open source and freely available) and I have to use it because it's the default for our main framework.
And in this context the DEL command from the Python side does not work, I had already tried it. DEL only deletes the python variable linked to the C++ object, not the object itself in memory, which is still owned by the C++ side...
...I know, it's not-standard I guess, and a bit complicated, sorry :-P
But following your hints, I'll profile my code and I'll come back to you with more details, as you suggested.
ADDITIONAL UPDATE:
Ok, following your suggestions, I instrumented my code with cProfile, and I discovered that actually the gc.collect() function is the function taking the most of the running time!!
Here the output from cProfile + pstats print_stats():
>>> p.sort_stats("time").print_stats(20)
Wed Oct 20 17:46:02 2010 mainProgram.profile
547303 function calls (542629 primitive calls) in 548.060 CPU seconds
Ordered by: internal time
List reduced from 727 to 20 due to restriction
ncalls tottime percall cumtime percall filename:lineno(function)
4 345.701 86.425 345.704 86.426 {gc.collect}
1 167.115 167.115 200.946 200.946 PlotD3PD_v3.2.py:2041(PlotSamplesBranches)
28 12.817 0.458 13.345 0.477 PlotROOTUtils.py:205(SaveItems)
9900 10.425 0.001 10.426 0.001 PlotD3PD_v3.2.py:1973(HistoStyle)
6622 5.188 0.001 5.278 0.001 PlotROOTUtils.py:403(__init__)
57 0.625 0.011 0.625 0.011 {built-in method load}
103 0.625 0.006 0.792 0.008 dbutils.py:41(DeadlockWrap)
14 0.475 0.034 0.475 0.034 {method 'dump' of 'cPickle.Pickler' objects}
6622 0.453 0.000 5.908 0.001 PlotROOTUtils.py:421(CreateCanvas)
26455 0.434 0.000 0.508 0.000 /opt/root/lib/ROOT.py:215(__getattr__)
[...]
>>> p.sort_stats("cumulative").print_stats(20)
Wed Oct 20 17:46:02 2010 mainProgram.profile
547303 function calls (542629 primitive calls) in 548.060 CPU seconds
Ordered by: cumulative time
List reduced from 727 to 20 due to restriction
ncalls tottime percall cumtime percall filename:lineno(function)
1 0.001 0.001 548.068 548.068 PlotD3PD_v3.2.py:2492(main)
4 0.000 0.000 346.756 86.689 /usr/lib//lib/python2.5/site-packages/guppy/heapy/Use.py:171(heap)
4 0.005 0.001 346.752 86.688 /usr/lib//lib/python2.5/site-packages/guppy/heapy/View.py:344(heap)
1 0.002 0.002 346.147 346.147 PlotD3PD_v3.2.py:2537(LogAndFinalize)
4 345.701 86.425 345.704 86.426 {gc.collect}
1 167.115 167.115 200.946 200.946 PlotD3PD_v3.2.py:2041(PlotBranches)
28 12.817 0.458 13.345 0.477 PlotROOTUtils.py:205(SaveItems)
9900 10.425 0.001 10.426 0.001 PlotD3PD_v3.2.py:1973(HistoStyle)
13202 0.336 0.000 6.818 0.001 PlotROOTUtils.py:431(PlottingCanvases)
6622 0.453 0.000 5.908 0.001 /root/svn_co/rbianchi/SoftwareDevelopment
[...]
>>>
So, in both outputs, sorted by "time" and by "cumulative" time respectively, gc.collect() is the function consuming the most of the running time of my program! :-P
And this is the output of the memory profiler Heapy, just before returning the main() program.
memory usage before return:
Partition of a set of 65901 objects. Total size = 4765572 bytes.
Index Count % Size % Cumulative % Kind (class / dict of class)
0 25437 39 1452444 30 1452444 30 str
1 6622 10 900592 19 2353036 49 dict of PlotROOTUtils.Canvas
2 109 0 567016 12 2920052 61 dict of module
3 7312 11 280644 6 3200696 67 tuple
4 6622 10 238392 5 3439088 72 0xa4ab74c
5 6622 10 185416 4 3624504 76 PlotROOTUtils.Canvas
6 2024 3 137632 3 3762136 79 types.CodeType
7 263 0 129080 3 3891216 82 dict (no owner)
8 254 0 119024 2 4010240 84 dict of type
9 254 0 109728 2 4119968 86 type
Index Count % Size % Cumulative % Kind (class / dict of class)
10 1917 3 107352 2 4264012 88 function
11 3647 5 102116 2 4366128 90 ROOT.MethodProxy
12 148 0 80800 2 4446928 92 dict of class
13 1109 2 39924 1 4486852 93 __builtin__.wrapper_descriptor
14 239 0 23136 0 4509988 93 list
15 87 0 22968 0 4532956 94 dict of guppy.etc.Glue.Interface
16 644 1 20608 0 4553564 94 types.BuiltinFunctionType
17 495 1 19800 0 4573364 94 __builtin__.weakref
18 23 0 11960 0 4585324 95 dict of guppy.etc.Glue.Share
19 367 1 11744 0 4597068 95 __builtin__.method_descriptor
Any idea why, or how to optimize the garbage collection?
Is there any more detailed check I can do? | Python garbage collection can be that slow? | 0 | -1 | 1 | 0 | 0 | 13,216 |
3,940,057 | 2010-10-15T06:45:00.000 | 1 | 1 | 0 | 0 | 0 | python,snmp,fitnesse,net-snmp,pysnmp | 1 | 3,968,271 | 0 | 1 | 1 | true | 0 | 0 | The engineTime and engineBoots values are probably what is messing you up because SNMPv3 requires they not go backwards. If you have an agent that is restarting from scratch and not incrementing it's boots count (which is illegal, but under tests I could see why you'd be doing that) then you'd need to reset the internal notion of boots and time.
However, setting them to 0 and 0 won't help because it'll assume those are defaults. You should, instead, change one of them to '1' which should trigger the override clause to actually use the values. Set the time to 1 and try it and I think it'll work (and if it doesn't, set them both to 1 instead and try that). | 1 | 1 | 0 | 0 | I'm trying to create automated integration tests for this hardware+software test subject which runs a SNMP agent as it's command interface. Our test setup looks like this: We're using Fitnesse as a test runner and PyFit to be able to write the tests in Python. We then use netsnmp with Python bindings to send SNMP commands. This works pretty well.
However, when I try to run a suite the SNMP agent (the test subject) is restarted (and usually at a different simulated time) which makes the internals of netsnmp get all sorts of interesting errors.
Turns out there is a lot of global state stored inside the netsnmp library like community and context names and problematically EngineTime and EngineBootCnt, which is used to prevent replay attacks in SNMP v3. This causes the agent to reject my snmp commands.
My problems is how do I reinitialise the netsnmp library (from the Python bindings) in a way that the internal global state are reset? The netsnmp.Session object in the Python bindings do take the parameter EngineTime and EngineBoots and setting them to 0 should reset them, but actually it doesn't seem to do that. I also do not know if there is other global state in there which needs to be reset.
I'm at a point where I think I need to rewrite the tests to use the pure python snmp library pysnmp, but I was hoping to avoid it. | Resetting all global internal state of the net-snmp library from the Python bindings | 0 | 1.2 | 1 | 0 | 0 | 731 |
3,945,750 | 2010-10-15T20:11:00.000 | 9 | 0 | 0 | 0 | 0 | python,beautifulsoup | 0 | 45,193,575 | 0 | 2 | 0 | false | 1 | 0 | with bs4 things have changed a little. so the code should look like this
soup = BeautifulSoup(htmlstring,'lxml')
soup.find_all('div', {'style':"width=300px;"}) | 1 | 29 | 0 | 0 | I can traverse generic tags easily with BS, but I don't know how to find specific tags. For example, how can I find all occurances of <div style="width=300px;">? Is this possible with BS? | Find a specific tag with BeautifulSoup | 0 | 1 | 1 | 0 | 1 | 62,029 |
3,949,739 | 2010-10-16T16:33:00.000 | 0 | 0 | 0 | 0 | 0 | python,html | 0 | 5,693,726 | 0 | 2 | 0 | false | 1 | 0 | urllib.unquote() on its own may still cause problems by throwing the exception:
UnicodeDecodeError: 'ascii' codec can't decode byte 0xc3 in position n: ordinal not in range(128)
In that case try:
print urllib.unquote("Ober%C3%B6sterreich.txt").decode("utf8") | 1 | 0 | 0 | 0 | I always found links in html source stored in such format, the question is how do I change such links back to what it's normally like?
Thanks a lot! | How to turn an encoded link such as "http%3A%2F%2Fexample.com%2Fwhatever" into "http://example.com/whatever" in python? | 0 | 0 | 1 | 0 | 1 | 797 |
3,955,077 | 2010-10-17T20:12:00.000 | 1 | 0 | 0 | 0 | 0 | python,image,r,analysis | 0 | 3,964,945 | 0 | 5 | 0 | false | 0 | 0 | Try the rgdal package. You will be able to read (import) and write (export) GeoTiff image files from/to R.
Marcio Pupin Mello | 1 | 15 | 1 | 0 | I would like to know how I would go about performing image analysis in R. My goal is to convert images into matrices (pixel-wise information), extract/quantify color, estimate the presence of shapes and compare images based on such metrics/patterns.
I am aware of relevant packages available in Python (suggestions relevant to Python are also welcome), but I am looking to accomplish these tasks in R.
Thank you for your feedback.
-Harsh | Image analysis in R | 0 | 0.039979 | 1 | 0 | 0 | 4,953 |
3,958,224 | 2010-10-18T10:24:00.000 | 1 | 0 | 0 | 1 | 0 | python,google-app-engine | 0 | 3,959,150 | 0 | 2 | 0 | false | 1 | 0 | Afaik you can not store files in App Engine programmatically. You can just store them, when uploading your app.
You can however store information in its data store. So you would need to deploy an app, that authenticates your user and then writs the image to the gae's data store | 1 | 1 | 0 | 0 | I am not running Django on AppEngine. I just want to use AppEngine as a content delivery network, basically a place I can host and serve images for free. It's for a personal side project.
The situation is this: I have the URL of an image hosted on another server/provider. Instead of hotlinking to that image its better to save it on AppEngine and serve it from there - this applies mostly for thumbnails.
My questions are these:
How do I authenticate from my Django app (let's say A) to my AppEngine app (B), so that only I can upload images
How do I make a request from A to B saying "Fetch the image on this URL, create a thumbnail and save it."
How do I tell B that "For this url return that image"
How can I handle errors or timeouts? And how can this be done asynchronously? | Uploading images from a django application to a Google AppEngine application | 0 | 0.099668 | 1 | 0 | 0 | 269 |
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