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http://rosettacode.org/wiki/Conjugate_transpose
Conjugate transpose
Suppose that a matrix M {\displaystyle M} contains complex numbers. Then the conjugate transpose of M {\displaystyle M} is a matrix M H {\displaystyle M^{H}} containing the complex conjugates of the matrix transposition of M {\displaystyle M} . ( M H ) j i = M i j ¯ {\displaystyle (M^{H})_{ji}={\overline {M_{ij}}}} This means that row j {\displaystyle j} , column i {\displaystyle i} of the conjugate transpose equals the complex conjugate of row i {\displaystyle i} , column j {\displaystyle j} of the original matrix. In the next list, M {\displaystyle M} must also be a square matrix. A Hermitian matrix equals its own conjugate transpose: M H = M {\displaystyle M^{H}=M} . A normal matrix is commutative in multiplication with its conjugate transpose: M H M = M M H {\displaystyle M^{H}M=MM^{H}} . A unitary matrix has its inverse equal to its conjugate transpose: M H = M − 1 {\displaystyle M^{H}=M^{-1}} . This is true iff M H M = I n {\displaystyle M^{H}M=I_{n}} and iff M M H = I n {\displaystyle MM^{H}=I_{n}} , where I n {\displaystyle I_{n}} is the identity matrix. Task Given some matrix of complex numbers, find its conjugate transpose. Also determine if the matrix is a: Hermitian matrix, normal matrix, or unitary matrix. See also MathWorld entry: conjugate transpose MathWorld entry: Hermitian matrix MathWorld entry: normal matrix MathWorld entry: unitary matrix
#PowerShell
PowerShell
  function conjugate-transpose($a) { $arr = @() if($a) { $n = $a.count - 1 if(0 -lt $n) { $m = ($a | foreach {$_.count} | measure-object -Minimum).Minimum - 1 if( 0 -le $m) { if (0 -lt $m) { $arr =@(0)*($m+1) foreach($i in 0..$m) { $arr[$i] = foreach($j in 0..$n) {@([System.Numerics.complex]::Conjugate($a[$j][$i]))} } } else {$arr = foreach($row in $a) {[System.Numerics.complex]::Conjugate($row[0])}} } } else {$arr = foreach($row in $a) {[System.Numerics.complex]::Conjugate($row[0])}} } $arr }   function multarrays-complex($a, $b) { $c = @() if($a -and $b) { $n = $a.count - 1 $m = $b[0].count - 1 $c = @([System.Numerics.complex]::new(0,0))*($n+1) foreach ($i in 0..$n) { $c[$i] = foreach ($j in 0..$m) { [System.Numerics.complex]$sum = [System.Numerics.complex]::new(0,0) foreach ($k in 0..$n){$sum = [System.Numerics.complex]::Add($sum, ([System.Numerics.complex]::Multiply($a[$i][$k],$b[$k][$j])))} $sum } } } $c }   function identity-complex($n) { if(0 -lt $n) { $array = @(0) * $n foreach ($i in 0..($n-1)) { $array[$i] = @([System.Numerics.complex]::new(0,0)) * $n $array[$i][$i] = [System.Numerics.complex]::new(1,0) } $array } else { @() } }   function are-eq ($a,$b) { -not (Compare-Object $a $b -SyncWindow 0)}   function show($a) { if($a) { 0..($a.Count - 1) | foreach{ if($a[$_]){"$($a[$_])"}else{""} } } } function complex($a,$b) {[System.Numerics.complex]::new($a,$b)}   $id2 = identity-complex 2 $m = @(@((complex 2 7), (complex 9 -5)),@((complex 3 4), (complex 8 -6))) $hm = conjugate-transpose $m $mhm = multarrays-complex $m $hm $hmm = multarrays-complex $hm $m "`$m =" show $m "" "`$hm = conjugate-transpose `$m =" show $hm "" "`$m * `$hm =" show $mhm "" "`$hm * `$m =" show $hmm "" "Hermitian? `$m = $(are-eq $m $hm)" "Normal? `$m = $(are-eq $mhm $hmm)" "Unitary? `$m = $((are-eq $id2 $hmm) -and (are-eq $id2 $mhm))"  
http://rosettacode.org/wiki/Compound_data_type
Compound data type
Data Structure This illustrates a data structure, a means of storing data within a program. You may see other such structures in the Data Structures category. Task Create a compound data type: Point(x,y) A compound data type is one that holds multiple independent values. Related task   Enumeration See also Array Associative array: Creation, Iteration Collections Compound data type Doubly-linked list: Definition, Element definition, Element insertion, List Traversal, Element Removal Linked list Queue: Definition, Usage Set Singly-linked list: Element definition, Element insertion, List Traversal, Element Removal Stack
#Crystal
Crystal
struct Point(T) getter x : T getter y : T def initialize(@x, @y) end end   puts Point(Int32).new 13, 12 #=> Point(Int32)(@x=13, @y=12)
http://rosettacode.org/wiki/Compound_data_type
Compound data type
Data Structure This illustrates a data structure, a means of storing data within a program. You may see other such structures in the Data Structures category. Task Create a compound data type: Point(x,y) A compound data type is one that holds multiple independent values. Related task   Enumeration See also Array Associative array: Creation, Iteration Collections Compound data type Doubly-linked list: Definition, Element definition, Element insertion, List Traversal, Element Removal Linked list Queue: Definition, Usage Set Singly-linked list: Element definition, Element insertion, List Traversal, Element Removal Stack
#D
D
void main() { // A normal POD struct // (if it's nested and it's not static then it has a hidden // field that points to the enclosing function): static struct Point { int x, y; }   auto p1 = Point(10, 20);   // It can also be parametrized on the coordinate type: static struct Pair(T) { T x, y; }   // A pair with integer coordinates: auto p2 = Pair!int(3, 5);   // A pair with floating point coordinates: auto p3 = Pair!double(3, 5);   // Classes (static inner): static class PointClass { int x, y; this(int x_, int y_) { this.x = x_; this.y = y_; } }   auto p4 = new PointClass(1, 2);   // There are also library-defined tuples: import std.typecons;   alias Tuple!(int,"x", int,"y") PointXY;   auto p5 = PointXY(3, 5);   // And even built-in "type tuples": import std.typetuple;   alias TypeTuple!(int, 5) p6;   static assert(is(p6[0] == int)); static assert(p6[1] == 5); }
http://rosettacode.org/wiki/Continued_fraction
Continued fraction
continued fraction Mathworld a 0 + b 1 a 1 + b 2 a 2 + b 3 a 3 + ⋱ {\displaystyle a_{0}+{\cfrac {b_{1}}{a_{1}+{\cfrac {b_{2}}{a_{2}+{\cfrac {b_{3}}{a_{3}+\ddots }}}}}}} The task is to write a program which generates such a number and prints a real representation of it. The code should be tested by calculating and printing the square root of 2, Napier's Constant, and Pi, using the following coefficients: For the square root of 2, use a 0 = 1 {\displaystyle a_{0}=1} then a N = 2 {\displaystyle a_{N}=2} . b N {\displaystyle b_{N}} is always 1 {\displaystyle 1} . 2 = 1 + 1 2 + 1 2 + 1 2 + ⋱ {\displaystyle {\sqrt {2}}=1+{\cfrac {1}{2+{\cfrac {1}{2+{\cfrac {1}{2+\ddots }}}}}}} For Napier's Constant, use a 0 = 2 {\displaystyle a_{0}=2} , then a N = N {\displaystyle a_{N}=N} . b 1 = 1 {\displaystyle b_{1}=1} then b N = N − 1 {\displaystyle b_{N}=N-1} . e = 2 + 1 1 + 1 2 + 2 3 + 3 4 + ⋱ {\displaystyle e=2+{\cfrac {1}{1+{\cfrac {1}{2+{\cfrac {2}{3+{\cfrac {3}{4+\ddots }}}}}}}}} For Pi, use a 0 = 3 {\displaystyle a_{0}=3} then a N = 6 {\displaystyle a_{N}=6} . b N = ( 2 N − 1 ) 2 {\displaystyle b_{N}=(2N-1)^{2}} . π = 3 + 1 6 + 9 6 + 25 6 + ⋱ {\displaystyle \pi =3+{\cfrac {1}{6+{\cfrac {9}{6+{\cfrac {25}{6+\ddots }}}}}}} See also   Continued fraction/Arithmetic for tasks that do arithmetic over continued fractions.
#Quackery
Quackery
[ $ "bigrat.qky" loadfile ] now!   [ 1 min [ table [ 1 1 ] [ 2 1 ] ] do ] is sqrt2 ( n --> n/d )   [ dup 2 min [ table [ drop 2 1 ] [ 1 ] [ dup 1 - ] ] do ] is napier ( n --> n/d )   [ dup 1 min [ table [ drop 3 1 ] [ 2 * 1 - dup * 6 swap ] ] do ] is pi ( n --> n/d )   [ ]'[ temp put 0 1 rot times [ i 1+ temp share do v+ 1/v ] 0 temp take do v+ ] is cf ( n --> n/d )   1000 cf sqrt2 10 point$ echo$ cr 1000 cf napier 10 point$ echo$ cr 1000 cf pi 10 point$ echo$ cr
http://rosettacode.org/wiki/Continued_fraction
Continued fraction
continued fraction Mathworld a 0 + b 1 a 1 + b 2 a 2 + b 3 a 3 + ⋱ {\displaystyle a_{0}+{\cfrac {b_{1}}{a_{1}+{\cfrac {b_{2}}{a_{2}+{\cfrac {b_{3}}{a_{3}+\ddots }}}}}}} The task is to write a program which generates such a number and prints a real representation of it. The code should be tested by calculating and printing the square root of 2, Napier's Constant, and Pi, using the following coefficients: For the square root of 2, use a 0 = 1 {\displaystyle a_{0}=1} then a N = 2 {\displaystyle a_{N}=2} . b N {\displaystyle b_{N}} is always 1 {\displaystyle 1} . 2 = 1 + 1 2 + 1 2 + 1 2 + ⋱ {\displaystyle {\sqrt {2}}=1+{\cfrac {1}{2+{\cfrac {1}{2+{\cfrac {1}{2+\ddots }}}}}}} For Napier's Constant, use a 0 = 2 {\displaystyle a_{0}=2} , then a N = N {\displaystyle a_{N}=N} . b 1 = 1 {\displaystyle b_{1}=1} then b N = N − 1 {\displaystyle b_{N}=N-1} . e = 2 + 1 1 + 1 2 + 2 3 + 3 4 + ⋱ {\displaystyle e=2+{\cfrac {1}{1+{\cfrac {1}{2+{\cfrac {2}{3+{\cfrac {3}{4+\ddots }}}}}}}}} For Pi, use a 0 = 3 {\displaystyle a_{0}=3} then a N = 6 {\displaystyle a_{N}=6} . b N = ( 2 N − 1 ) 2 {\displaystyle b_{N}=(2N-1)^{2}} . π = 3 + 1 6 + 9 6 + 25 6 + ⋱ {\displaystyle \pi =3+{\cfrac {1}{6+{\cfrac {9}{6+{\cfrac {25}{6+\ddots }}}}}}} See also   Continued fraction/Arithmetic for tasks that do arithmetic over continued fractions.
#Racket
Racket
  #lang racket (define (calc cf n) (match/values (cf 0) [(a0 b0) (+ a0 (for/fold ([t 0.0]) ([i (in-range (+ n 1) 0 -1)]) (match/values (cf i) [(a b) (/ b (+ a t))])))]))   (define (cf-sqrt i) (values (if (> i 0) 2 1) 1)) (define (cf-napier i) (values (if (> i 0) i 2) (if (> i 1) (- i 1) 1))) (define (cf-pi i) (values (if (> i 0) 6 3) (sqr (- (* 2 i) 1))))   (calc cf-sqrt 200) (calc cf-napier 200) (calc cf-pi 200)  
http://rosettacode.org/wiki/Copy_a_string
Copy a string
This task is about copying a string. Task Where it is relevant, distinguish between copying the contents of a string versus making an additional reference to an existing string. Other tasks related to string operations: Metrics Array length String length Copy a string Empty string  (assignment) Counting Word frequency Letter frequency Jewels and stones I before E except after C Bioinformatics/base count Count occurrences of a substring Count how many vowels and consonants occur in a string Remove/replace XXXX redacted Conjugate a Latin verb Remove vowels from a string String interpolation (included) Strip block comments Strip comments from a string Strip a set of characters from a string Strip whitespace from a string -- top and tail Strip control codes and extended characters from a string Anagrams/Derangements/shuffling Word wheel ABC problem Sattolo cycle Knuth shuffle Ordered words Superpermutation minimisation Textonyms (using a phone text pad) Anagrams Anagrams/Deranged anagrams Permutations/Derangements Find/Search/Determine ABC words Odd words Word ladder Semordnilap Word search Wordiff  (game) String matching Tea cup rim text Alternade words Changeable words State name puzzle String comparison Unique characters Unique characters in each string Extract file extension Levenshtein distance Palindrome detection Common list elements Longest common suffix Longest common prefix Compare a list of strings Longest common substring Find common directory path Words from neighbour ones Change e letters to i in words Non-continuous subsequences Longest common subsequence Longest palindromic substrings Longest increasing subsequence Words containing "the" substring Sum of the digits of n is substring of n Determine if a string is numeric Determine if a string is collapsible Determine if a string is squeezable Determine if a string has all unique characters Determine if a string has all the same characters Longest substrings without repeating characters Find words which contains all the vowels Find words which contains most consonants Find words which contains more than 3 vowels Find words which first and last three letters are equals Find words which odd letters are consonants and even letters are vowels or vice_versa Formatting Substring Rep-string Word wrap String case Align columns Literals/String Repeat a string Brace expansion Brace expansion using ranges Reverse a string Phrase reversals Comma quibbling Special characters String concatenation Substring/Top and tail Commatizing numbers Reverse words in a string Suffixation of decimal numbers Long literals, with continuations Numerical and alphabetical suffixes Abbreviations, easy Abbreviations, simple Abbreviations, automatic Song lyrics/poems/Mad Libs/phrases Mad Libs Magic 8-ball 99 Bottles of Beer The Name Game (a song) The Old lady swallowed a fly The Twelve Days of Christmas Tokenize Text between Tokenize a string Word break problem Tokenize a string with escaping Split a character string based on change of character Sequences Show ASCII table De Bruijn sequences Self-referential sequences Generate lower case ASCII alphabet
#ooRexx
ooRexx
/* Rexx *************************************************************** * 16.05.2013 Walter Pachl **********************************************************************/   s1 = 'This is a Rexx string' s2 = s1 /* does not copy the string */   Say 's1='s1 Say 's2='s2 i1=s1~identityhash; Say 's1~identityhash='i1 i2=s2~identityhash; Say 's2~identityhash='i2   s2 = s2~changestr('*', '*') /* creates a modified copy */   Say 's1='s1 Say 's2='s2 i1=s1~identityhash; Say 's1~identityhash='i1 i2=s2~identityhash; Say 's2~identityhash='i2
http://rosettacode.org/wiki/Copy_a_string
Copy a string
This task is about copying a string. Task Where it is relevant, distinguish between copying the contents of a string versus making an additional reference to an existing string. Other tasks related to string operations: Metrics Array length String length Copy a string Empty string  (assignment) Counting Word frequency Letter frequency Jewels and stones I before E except after C Bioinformatics/base count Count occurrences of a substring Count how many vowels and consonants occur in a string Remove/replace XXXX redacted Conjugate a Latin verb Remove vowels from a string String interpolation (included) Strip block comments Strip comments from a string Strip a set of characters from a string Strip whitespace from a string -- top and tail Strip control codes and extended characters from a string Anagrams/Derangements/shuffling Word wheel ABC problem Sattolo cycle Knuth shuffle Ordered words Superpermutation minimisation Textonyms (using a phone text pad) Anagrams Anagrams/Deranged anagrams Permutations/Derangements Find/Search/Determine ABC words Odd words Word ladder Semordnilap Word search Wordiff  (game) String matching Tea cup rim text Alternade words Changeable words State name puzzle String comparison Unique characters Unique characters in each string Extract file extension Levenshtein distance Palindrome detection Common list elements Longest common suffix Longest common prefix Compare a list of strings Longest common substring Find common directory path Words from neighbour ones Change e letters to i in words Non-continuous subsequences Longest common subsequence Longest palindromic substrings Longest increasing subsequence Words containing "the" substring Sum of the digits of n is substring of n Determine if a string is numeric Determine if a string is collapsible Determine if a string is squeezable Determine if a string has all unique characters Determine if a string has all the same characters Longest substrings without repeating characters Find words which contains all the vowels Find words which contains most consonants Find words which contains more than 3 vowels Find words which first and last three letters are equals Find words which odd letters are consonants and even letters are vowels or vice_versa Formatting Substring Rep-string Word wrap String case Align columns Literals/String Repeat a string Brace expansion Brace expansion using ranges Reverse a string Phrase reversals Comma quibbling Special characters String concatenation Substring/Top and tail Commatizing numbers Reverse words in a string Suffixation of decimal numbers Long literals, with continuations Numerical and alphabetical suffixes Abbreviations, easy Abbreviations, simple Abbreviations, automatic Song lyrics/poems/Mad Libs/phrases Mad Libs Magic 8-ball 99 Bottles of Beer The Name Game (a song) The Old lady swallowed a fly The Twelve Days of Christmas Tokenize Text between Tokenize a string Word break problem Tokenize a string with escaping Split a character string based on change of character Sequences Show ASCII table De Bruijn sequences Self-referential sequences Generate lower case ASCII alphabet
#OxygenBasic
OxygenBasic
  string s, t="hello" s=t  
http://rosettacode.org/wiki/Constrained_random_points_on_a_circle
Constrained random points on a circle
Task Generate 100 <x,y> coordinate pairs such that x and y are integers sampled from the uniform distribution with the condition that 10 ≤ x 2 + y 2 ≤ 15 {\displaystyle 10\leq {\sqrt {x^{2}+y^{2}}}\leq 15} . Then display/plot them. The outcome should be a "fuzzy" circle. The actual number of points plotted may be less than 100, given that some pairs may be generated more than once. There are several possible approaches to accomplish this. Here are two possible algorithms. 1) Generate random pairs of integers and filter out those that don't satisfy this condition: 10 ≤ x 2 + y 2 ≤ 15 {\displaystyle 10\leq {\sqrt {x^{2}+y^{2}}}\leq 15} . 2) Precalculate the set of all possible points (there are 404 of them) and select randomly from this set.
#Kotlin
Kotlin
// version 1.1.3   fun main(args: Array<String>) { val r = java.util.Random() val points = Array(31) { CharArray(31) { ' ' } } var count = 0 while (count < 100) { val x = r.nextInt(31) - 15 val y = r.nextInt(31) - 15 val h = x * x + y * y if (h in 100..225) { points[x + 15][y + 15] = 'o' count++ } } for (i in 0..30) println(points[i].joinToString("")) }
http://rosettacode.org/wiki/Convex_hull
Convex hull
Find the points which form a convex hull from a set of arbitrary two dimensional points. For example, given the points (16,3), (12,17), (0,6), (-4,-6), (16,6), (16,-7), (16,-3), (17,-4), (5,19), (19,-8), (3,16), (12,13), (3,-4), (17,5), (-3,15), (-3,-9), (0,11), (-9,-3), (-4,-2) and (12,10) the convex hull would be (-9,-3), (-3,-9), (19,-8), (17,5), (12,17), (5,19) and (-3,15). See also Convex Hull (youtube) http://www.geeksforgeeks.org/convex-hull-set-2-graham-scan/
#Perl
Perl
use strict; use warnings; use feature 'say';   { package Point; use Class::Struct; struct( x => '$', y => '$',); sub print { '(' . $_->x . ', ' . $_->y . ')' } }   sub ccw { my($a, $b, $c) = @_; ($b->x - $a->x)*($c->y - $a->y) - ($b->y - $a->y)*($c->x - $a->x); }   sub tangent { my($a, $b) = @_; my $opp = $b->x - $a->x; my $adj = $b->y - $a->y; $adj != 0 ? $opp / $adj : 1E99; }   sub graham_scan { our @coords; local *coords = shift; my @sp = sort { $a->y <=> $b->y or $a->x <=> $b->x } map { Point->new( x => $_->[0], y => $_->[1] ) } @coords;   # need at least 3 points to make a hull return @sp if @sp < 3;   # first point on hull is minimum y point my @h = shift @sp;   # re-sort the points by angle, secondary on x (classic Schwartzian) @sp = map { $sp[$_->[0]] } sort { $b->[1] <=> $a->[1] or $a->[2] <=> $b->[2] } map { [$_, tangent($h[0], $sp[$_]), $sp[$_]->x] } 0..$#sp;   # first point of re-sorted list is guaranteed to be on hull push @h, shift @sp;   # check through the remaining list making sure that there is always a positive angle for my $point (@sp) { if (ccw( @h[-2,-1], $point ) >= 0) { push @h, $point; } else { pop @h; redo; } } @h }   my @hull_1 = graham_scan( [[16, 3], [12,17], [ 0, 6], [-4,-6], [16, 6], [16,-7], [16,-3], [17,-4], [ 5,19], [19,-8], [ 3,16], [12,13], [ 3,-4], [17, 5], [-3,15], [-3,-9], [ 0,11], [-9,-3], [-4,-2], [12,10]] );   my @hull_2 = graham_scan( [[16, 3], [12,17], [ 0, 6], [-4,-6], [16, 6], [16,-7], [16,-3], [17,-4], [ 5,19], [19,-8], [ 3,16], [12,13], [ 3,-4], [17, 5], [-3,15], [-3,-9], [ 0,11], [-9,-3], [-4,-2], [12,10], [14,-9], [1,-9]] );   my $list = join ' ', map { Point::print($_) } @hull_1; say "Convex Hull (@{[scalar @hull_1]} points): [$list]"; $list = join ' ', map { Point::print($_) } @hull_2; say "Convex Hull (@{[scalar @hull_2]} points): [$list]";  
http://rosettacode.org/wiki/Convert_seconds_to_compound_duration
Convert seconds to compound duration
Task Write a function or program which:   takes a positive integer representing a duration in seconds as input (e.g., 100), and   returns a string which shows the same duration decomposed into:   weeks,   days,   hours,   minutes,   and   seconds. This is detailed below (e.g., "2 hr, 59 sec"). Demonstrate that it passes the following three test-cases: Test Cases input number output string 7259 2 hr, 59 sec 86400 1 d 6000000 9 wk, 6 d, 10 hr, 40 min Details The following five units should be used: unit suffix used in output conversion week wk 1 week = 7 days day d 1 day = 24 hours hour hr 1 hour = 60 minutes minute min 1 minute = 60 seconds second sec However, only include quantities with non-zero values in the output (e.g., return "1 d" and not "0 wk, 1 d, 0 hr, 0 min, 0 sec"). Give larger units precedence over smaller ones as much as possible (e.g., return 2 min, 10 sec and not 1 min, 70 sec or 130 sec) Mimic the formatting shown in the test-cases (quantities sorted from largest unit to smallest and separated by comma+space; value and unit of each quantity separated by space).
#Racket
Racket
#lang racket/base (require racket/string racket/list)   (define (seconds->compound-durations s) (define-values (w d.h.m.s) (for/fold ((prev-q s) (rs (list))) ((Q (in-list (list 60 60 24 7)))) (define-values (q r) (quotient/remainder prev-q Q)) (values q (cons r rs)))) (cons w d.h.m.s))   (define (maybe-suffix v n) (and (positive? v) (format "~a ~a" v n)))   (define (seconds->compound-duration-string s) (string-join (filter-map maybe-suffix (seconds->compound-durations s) '("wk" "d" "hr" "min" "sec")) ", "))   (module+ test (require rackunit) (check-equal? (seconds->compound-durations 7259) (list 0 0 2 0 59)) (check-equal? (seconds->compound-durations 86400) (list 0 1 0 0 0)) (check-equal? (seconds->compound-durations 6000000) (list 9 6 10 40 0))   (check-equal? (seconds->compound-duration-string 7259) "2 hr, 59 sec") (check-equal? (seconds->compound-duration-string 86400) "1 d") (check-equal? (seconds->compound-duration-string 6000000) "9 wk, 6 d, 10 hr, 40 min"))   ;; Tim Brown 2015-07-21
http://rosettacode.org/wiki/Convert_seconds_to_compound_duration
Convert seconds to compound duration
Task Write a function or program which:   takes a positive integer representing a duration in seconds as input (e.g., 100), and   returns a string which shows the same duration decomposed into:   weeks,   days,   hours,   minutes,   and   seconds. This is detailed below (e.g., "2 hr, 59 sec"). Demonstrate that it passes the following three test-cases: Test Cases input number output string 7259 2 hr, 59 sec 86400 1 d 6000000 9 wk, 6 d, 10 hr, 40 min Details The following five units should be used: unit suffix used in output conversion week wk 1 week = 7 days day d 1 day = 24 hours hour hr 1 hour = 60 minutes minute min 1 minute = 60 seconds second sec However, only include quantities with non-zero values in the output (e.g., return "1 d" and not "0 wk, 1 d, 0 hr, 0 min, 0 sec"). Give larger units precedence over smaller ones as much as possible (e.g., return 2 min, 10 sec and not 1 min, 70 sec or 130 sec) Mimic the formatting shown in the test-cases (quantities sorted from largest unit to smallest and separated by comma+space; value and unit of each quantity separated by space).
#Raku
Raku
sub compound-duration ($seconds) { ($seconds.polymod(60, 60, 24, 7) Z <sec min hr d wk>) .grep(*[0]).reverse.join(", ") }   # Demonstration:   for 7259, 86400, 6000000 { say "{.fmt: '%7d'} sec = {compound-duration $_}"; }
http://rosettacode.org/wiki/Concurrent_computing
Concurrent computing
Task Using either native language concurrency syntax or freely available libraries, write a program to display the strings "Enjoy" "Rosetta" "Code", one string per line, in random order. Concurrency syntax must use threads, tasks, co-routines, or whatever concurrency is called in your language.
#Fortran
Fortran
program concurrency implicit none character(len=*), parameter :: str1 = 'Enjoy' character(len=*), parameter :: str2 = 'Rosetta' character(len=*), parameter :: str3 = 'Code' integer :: i real :: h real, parameter :: one_third = 1.0e0/3 real, parameter :: two_thirds = 2.0e0/3   interface integer function omp_get_thread_num end function omp_get_thread_num end interface interface integer function omp_get_num_threads end function omp_get_num_threads end interface   ! Use OpenMP to create a team of threads !$omp parallel do private(i,h) do i=1,20 ! First time through the master thread output the number of threads ! in the team if (omp_get_thread_num() == 0 .and. i == 1) then write(*,'(a,i0,a)') 'Using ',omp_get_num_threads(),' threads' end if   ! Randomize the order call random_number(h)   !$omp critical if (h < one_third) then write(*,'(a)') str1 else if (h < two_thirds) then write(*,'(a)') str2 else write(*,'(a)') str3 end if !$omp end critical end do !$omp end parallel do   end program concurrency
http://rosettacode.org/wiki/Conjugate_transpose
Conjugate transpose
Suppose that a matrix M {\displaystyle M} contains complex numbers. Then the conjugate transpose of M {\displaystyle M} is a matrix M H {\displaystyle M^{H}} containing the complex conjugates of the matrix transposition of M {\displaystyle M} . ( M H ) j i = M i j ¯ {\displaystyle (M^{H})_{ji}={\overline {M_{ij}}}} This means that row j {\displaystyle j} , column i {\displaystyle i} of the conjugate transpose equals the complex conjugate of row i {\displaystyle i} , column j {\displaystyle j} of the original matrix. In the next list, M {\displaystyle M} must also be a square matrix. A Hermitian matrix equals its own conjugate transpose: M H = M {\displaystyle M^{H}=M} . A normal matrix is commutative in multiplication with its conjugate transpose: M H M = M M H {\displaystyle M^{H}M=MM^{H}} . A unitary matrix has its inverse equal to its conjugate transpose: M H = M − 1 {\displaystyle M^{H}=M^{-1}} . This is true iff M H M = I n {\displaystyle M^{H}M=I_{n}} and iff M M H = I n {\displaystyle MM^{H}=I_{n}} , where I n {\displaystyle I_{n}} is the identity matrix. Task Given some matrix of complex numbers, find its conjugate transpose. Also determine if the matrix is a: Hermitian matrix, normal matrix, or unitary matrix. See also MathWorld entry: conjugate transpose MathWorld entry: Hermitian matrix MathWorld entry: normal matrix MathWorld entry: unitary matrix
#Python
Python
def conjugate_transpose(m): return tuple(tuple(n.conjugate() for n in row) for row in zip(*m))   def mmul( ma, mb): return tuple(tuple(sum( ea*eb for ea,eb in zip(a,b)) for b in zip(*mb)) for a in ma)   def mi(size): 'Complex Identity matrix' sz = range(size) m = [[0 + 0j for i in sz] for j in sz] for i in range(size): m[i][i] = 1 + 0j return tuple(tuple(row) for row in m)   def __allsame(vector): first, rest = vector[0], vector[1:] return all(i == first for i in rest)   def __allnearsame(vector, eps=1e-14): first, rest = vector[0], vector[1:] return all(abs(first.real - i.real) < eps and abs(first.imag - i.imag) < eps for i in rest)   def isequal(matrices, eps=1e-14): 'Check any number of matrices for equality within eps' x = [len(m) for m in matrices] if not __allsame(x): return False y = [len(m[0]) for m in matrices] if not __allsame(y): return False for s in range(x[0]): for t in range(y[0]): if not __allnearsame([m[s][t] for m in matrices], eps): return False return True     def ishermitian(m, ct): return isequal([m, ct])   def isnormal(m, ct): return isequal([mmul(m, ct), mmul(ct, m)])   def isunitary(m, ct): mct, ctm = mmul(m, ct), mmul(ct, m) mctx, mcty, cmx, ctmy = len(mct), len(mct[0]), len(ctm), len(ctm[0]) ident = mi(mctx) return isequal([mct, ctm, ident])   def printm(comment, m): print(comment) fields = [['%g%+gj' % (f.real, f.imag) for f in row] for row in m] width = max(max(len(f) for f in row) for row in fields) lines = (', '.join('%*s' % (width, f) for f in row) for row in fields) print('\n'.join(lines))   if __name__ == '__main__': for matrix in [ ((( 3.000+0.000j), (+2.000+1.000j)), (( 2.000-1.000j), (+1.000+0.000j))),   ((( 1.000+0.000j), (+1.000+0.000j), (+0.000+0.000j)), (( 0.000+0.000j), (+1.000+0.000j), (+1.000+0.000j)), (( 1.000+0.000j), (+0.000+0.000j), (+1.000+0.000j))),   ((( 2**0.5/2+0.000j), (+2**0.5/2+0.000j), (+0.000+0.000j)), (( 0.000+2**0.5/2j), (+0.000-2**0.5/2j), (+0.000+0.000j)), (( 0.000+0.000j), (+0.000+0.000j), (+0.000+1.000j)))]: printm('\nMatrix:', matrix) ct = conjugate_transpose(matrix) printm('Its conjugate transpose:', ct) print('Hermitian? %s.' % ishermitian(matrix, ct)) print('Normal?  %s.' % isnormal(matrix, ct)) print('Unitary?  %s.' % isunitary(matrix, ct))
http://rosettacode.org/wiki/Compound_data_type
Compound data type
Data Structure This illustrates a data structure, a means of storing data within a program. You may see other such structures in the Data Structures category. Task Create a compound data type: Point(x,y) A compound data type is one that holds multiple independent values. Related task   Enumeration See also Array Associative array: Creation, Iteration Collections Compound data type Doubly-linked list: Definition, Element definition, Element insertion, List Traversal, Element Removal Linked list Queue: Definition, Usage Set Singly-linked list: Element definition, Element insertion, List Traversal, Element Removal Stack
#Delphi
Delphi
TPoint = record X: Longint; Y: Longint; end;  
http://rosettacode.org/wiki/Compound_data_type
Compound data type
Data Structure This illustrates a data structure, a means of storing data within a program. You may see other such structures in the Data Structures category. Task Create a compound data type: Point(x,y) A compound data type is one that holds multiple independent values. Related task   Enumeration See also Array Associative array: Creation, Iteration Collections Compound data type Doubly-linked list: Definition, Element definition, Element insertion, List Traversal, Element Removal Linked list Queue: Definition, Usage Set Singly-linked list: Element definition, Element insertion, List Traversal, Element Removal Stack
#E
E
def makePoint(x, y) { def point { to getX() { return x } to getY() { return y } } return point }
http://rosettacode.org/wiki/Continued_fraction
Continued fraction
continued fraction Mathworld a 0 + b 1 a 1 + b 2 a 2 + b 3 a 3 + ⋱ {\displaystyle a_{0}+{\cfrac {b_{1}}{a_{1}+{\cfrac {b_{2}}{a_{2}+{\cfrac {b_{3}}{a_{3}+\ddots }}}}}}} The task is to write a program which generates such a number and prints a real representation of it. The code should be tested by calculating and printing the square root of 2, Napier's Constant, and Pi, using the following coefficients: For the square root of 2, use a 0 = 1 {\displaystyle a_{0}=1} then a N = 2 {\displaystyle a_{N}=2} . b N {\displaystyle b_{N}} is always 1 {\displaystyle 1} . 2 = 1 + 1 2 + 1 2 + 1 2 + ⋱ {\displaystyle {\sqrt {2}}=1+{\cfrac {1}{2+{\cfrac {1}{2+{\cfrac {1}{2+\ddots }}}}}}} For Napier's Constant, use a 0 = 2 {\displaystyle a_{0}=2} , then a N = N {\displaystyle a_{N}=N} . b 1 = 1 {\displaystyle b_{1}=1} then b N = N − 1 {\displaystyle b_{N}=N-1} . e = 2 + 1 1 + 1 2 + 2 3 + 3 4 + ⋱ {\displaystyle e=2+{\cfrac {1}{1+{\cfrac {1}{2+{\cfrac {2}{3+{\cfrac {3}{4+\ddots }}}}}}}}} For Pi, use a 0 = 3 {\displaystyle a_{0}=3} then a N = 6 {\displaystyle a_{N}=6} . b N = ( 2 N − 1 ) 2 {\displaystyle b_{N}=(2N-1)^{2}} . π = 3 + 1 6 + 9 6 + 25 6 + ⋱ {\displaystyle \pi =3+{\cfrac {1}{6+{\cfrac {9}{6+{\cfrac {25}{6+\ddots }}}}}}} See also   Continued fraction/Arithmetic for tasks that do arithmetic over continued fractions.
#Raku
Raku
sub continued-fraction(:@a, :@b, Int :$n = 100) { my $x = @a[$n - 1]; $x = @a[$_ - 1] + @b[$_] / $x for reverse 1 ..^ $n; $x; }   printf "√2 ≈%.9f\n", continued-fraction(:a(1, |(2 xx *)), :b(Nil, |(1 xx *))); printf "e ≈%.9f\n", continued-fraction(:a(2, |(1 .. *)), :b(Nil, 1, |(1 .. *))); printf "π ≈%.9f\n", continued-fraction(:a(3, |(6 xx *)), :b(Nil, |((1, 3, 5 ... *) X** 2)));
http://rosettacode.org/wiki/Copy_a_string
Copy a string
This task is about copying a string. Task Where it is relevant, distinguish between copying the contents of a string versus making an additional reference to an existing string. Other tasks related to string operations: Metrics Array length String length Copy a string Empty string  (assignment) Counting Word frequency Letter frequency Jewels and stones I before E except after C Bioinformatics/base count Count occurrences of a substring Count how many vowels and consonants occur in a string Remove/replace XXXX redacted Conjugate a Latin verb Remove vowels from a string String interpolation (included) Strip block comments Strip comments from a string Strip a set of characters from a string Strip whitespace from a string -- top and tail Strip control codes and extended characters from a string Anagrams/Derangements/shuffling Word wheel ABC problem Sattolo cycle Knuth shuffle Ordered words Superpermutation minimisation Textonyms (using a phone text pad) Anagrams Anagrams/Deranged anagrams Permutations/Derangements Find/Search/Determine ABC words Odd words Word ladder Semordnilap Word search Wordiff  (game) String matching Tea cup rim text Alternade words Changeable words State name puzzle String comparison Unique characters Unique characters in each string Extract file extension Levenshtein distance Palindrome detection Common list elements Longest common suffix Longest common prefix Compare a list of strings Longest common substring Find common directory path Words from neighbour ones Change e letters to i in words Non-continuous subsequences Longest common subsequence Longest palindromic substrings Longest increasing subsequence Words containing "the" substring Sum of the digits of n is substring of n Determine if a string is numeric Determine if a string is collapsible Determine if a string is squeezable Determine if a string has all unique characters Determine if a string has all the same characters Longest substrings without repeating characters Find words which contains all the vowels Find words which contains most consonants Find words which contains more than 3 vowels Find words which first and last three letters are equals Find words which odd letters are consonants and even letters are vowels or vice_versa Formatting Substring Rep-string Word wrap String case Align columns Literals/String Repeat a string Brace expansion Brace expansion using ranges Reverse a string Phrase reversals Comma quibbling Special characters String concatenation Substring/Top and tail Commatizing numbers Reverse words in a string Suffixation of decimal numbers Long literals, with continuations Numerical and alphabetical suffixes Abbreviations, easy Abbreviations, simple Abbreviations, automatic Song lyrics/poems/Mad Libs/phrases Mad Libs Magic 8-ball 99 Bottles of Beer The Name Game (a song) The Old lady swallowed a fly The Twelve Days of Christmas Tokenize Text between Tokenize a string Word break problem Tokenize a string with escaping Split a character string based on change of character Sequences Show ASCII table De Bruijn sequences Self-referential sequences Generate lower case ASCII alphabet
#PARI.2FGP
PARI/GP
s1=s
http://rosettacode.org/wiki/Copy_a_string
Copy a string
This task is about copying a string. Task Where it is relevant, distinguish between copying the contents of a string versus making an additional reference to an existing string. Other tasks related to string operations: Metrics Array length String length Copy a string Empty string  (assignment) Counting Word frequency Letter frequency Jewels and stones I before E except after C Bioinformatics/base count Count occurrences of a substring Count how many vowels and consonants occur in a string Remove/replace XXXX redacted Conjugate a Latin verb Remove vowels from a string String interpolation (included) Strip block comments Strip comments from a string Strip a set of characters from a string Strip whitespace from a string -- top and tail Strip control codes and extended characters from a string Anagrams/Derangements/shuffling Word wheel ABC problem Sattolo cycle Knuth shuffle Ordered words Superpermutation minimisation Textonyms (using a phone text pad) Anagrams Anagrams/Deranged anagrams Permutations/Derangements Find/Search/Determine ABC words Odd words Word ladder Semordnilap Word search Wordiff  (game) String matching Tea cup rim text Alternade words Changeable words State name puzzle String comparison Unique characters Unique characters in each string Extract file extension Levenshtein distance Palindrome detection Common list elements Longest common suffix Longest common prefix Compare a list of strings Longest common substring Find common directory path Words from neighbour ones Change e letters to i in words Non-continuous subsequences Longest common subsequence Longest palindromic substrings Longest increasing subsequence Words containing "the" substring Sum of the digits of n is substring of n Determine if a string is numeric Determine if a string is collapsible Determine if a string is squeezable Determine if a string has all unique characters Determine if a string has all the same characters Longest substrings without repeating characters Find words which contains all the vowels Find words which contains most consonants Find words which contains more than 3 vowels Find words which first and last three letters are equals Find words which odd letters are consonants and even letters are vowels or vice_versa Formatting Substring Rep-string Word wrap String case Align columns Literals/String Repeat a string Brace expansion Brace expansion using ranges Reverse a string Phrase reversals Comma quibbling Special characters String concatenation Substring/Top and tail Commatizing numbers Reverse words in a string Suffixation of decimal numbers Long literals, with continuations Numerical and alphabetical suffixes Abbreviations, easy Abbreviations, simple Abbreviations, automatic Song lyrics/poems/Mad Libs/phrases Mad Libs Magic 8-ball 99 Bottles of Beer The Name Game (a song) The Old lady swallowed a fly The Twelve Days of Christmas Tokenize Text between Tokenize a string Word break problem Tokenize a string with escaping Split a character string based on change of character Sequences Show ASCII table De Bruijn sequences Self-referential sequences Generate lower case ASCII alphabet
#Pascal
Pascal
program in,out;   type   pString = ^string;   var   s1,s2 : string ; pStr : pString ;   begin   /* direct copy */ s1 := 'Now is the time for all good men to come to the aid of their party.' s2 := s1 ;   writeln(s1); writeln(s2);   /* By Reference */ pStr := @s1 ; writeln(pStr^);   pStr := @s2 ; writeln(pStr^);   end;
http://rosettacode.org/wiki/Constrained_random_points_on_a_circle
Constrained random points on a circle
Task Generate 100 <x,y> coordinate pairs such that x and y are integers sampled from the uniform distribution with the condition that 10 ≤ x 2 + y 2 ≤ 15 {\displaystyle 10\leq {\sqrt {x^{2}+y^{2}}}\leq 15} . Then display/plot them. The outcome should be a "fuzzy" circle. The actual number of points plotted may be less than 100, given that some pairs may be generated more than once. There are several possible approaches to accomplish this. Here are two possible algorithms. 1) Generate random pairs of integers and filter out those that don't satisfy this condition: 10 ≤ x 2 + y 2 ≤ 15 {\displaystyle 10\leq {\sqrt {x^{2}+y^{2}}}\leq 15} . 2) Precalculate the set of all possible points (there are 404 of them) and select randomly from this set.
#Lambdatalk
Lambdatalk
  {def circ {lambda {:cx :cy :r} {div {@ style="position:absolute; top: {- :cy :r}px; left: {- :cx :r}px; width: {* 2 :r}px; height: {* 2 :r}px; border: 1px solid #000; border-radius: :rpx;"}} }} -> circ   {def fuzzy_circle {lambda {:cx :cy :rmin :rmax :n} {circ :cx :cy :rmax} {circ :cx :cy :rmin} {S.map {{lambda {:cx :cy :rmin :rmax :i} {let { {:cx :cx} {:cy :cy} {:rmin :rmin} {:rmax :rmax} {:x {- {round {* {random} {* 2 :rmax}}} :rmax}} {:y {- {round {* {random} {* 2 :rmax}}} :rmax}} } {let { {:x {+ :cx :x }} {:y {+ :cy :y }} {:rr {+ {* :x :x} {* :y :y}}} {:r2min {* :rmin :rmin}} {:r2max {* :rmax :rmax}} } {if {or {< :rr :r2min} {> :rr :r2max}} then else {circ :x :y 2}} }}} :cx :cy :rmin :rmax} {S.serie 1 :n}} }} -> fuzzy_circle   {fuzzy_circle 200 700 80 120 1000} -> plots 1000 dots between the circles r=80 and r=120 centered at [200,700] directly in the wiki page (out of any canvas or svg contexts) as it can be seen in http://lambdaway.free.fr/lambdawalks/?view=fuzzy_circle    
http://rosettacode.org/wiki/Convex_hull
Convex hull
Find the points which form a convex hull from a set of arbitrary two dimensional points. For example, given the points (16,3), (12,17), (0,6), (-4,-6), (16,6), (16,-7), (16,-3), (17,-4), (5,19), (19,-8), (3,16), (12,13), (3,-4), (17,5), (-3,15), (-3,-9), (0,11), (-9,-3), (-4,-2) and (12,10) the convex hull would be (-9,-3), (-3,-9), (19,-8), (17,5), (12,17), (5,19) and (-3,15). See also Convex Hull (youtube) http://www.geeksforgeeks.org/convex-hull-set-2-graham-scan/
#Phix
Phix
-- -- demo/rosetta/Convex_hull.exw -- ============================ -- with javascript_semantics constant tests = {{{16, 3}, {12, 17}, { 0, 6}, {-4, -6}, {16, 6}, {16, -7}, {16, -3}, {17, -4}, { 5, 19}, {19, -8}, { 3, 16}, {12, 13}, { 3, -4}, {17, 5}, {-3, 15}, {-3, -9}, { 0, 11}, {-9, -3}, {-4, -2}, {12, 10}}, {{16, 3}, {12, 17}, { 0, 6}, {-4, -6}, {16, 6}, {16, -7}, {16, -3}, {17, -4}, { 5, 19}, {19, -8}, { 3, 16}, {12, 13}, { 3, -4}, {17, 5}, {-3, 15}, {-3, -9}, { 0, 11}, {-9, -3}, {-4, -2}, {12, 10}, {1,-9}, {1,-9}}, {{0,0}, {5,5}, {5,0}, {0,5}}, {{0,0}, {0,1}, {0,2}, {1,0}, {1,1}, {1,2}, {2,0}, {2,1}, {2,2}}, {{-8,-8}, {-8,4}, {-8,16}, { 4,-8}, { 4,4}, { 4,16}, {16,-8}, {16,4}, {16,16}}} integer t = 1 -- idx to tests, for the GTITLE. enum x, y function ccw(sequence a, b, c) return (b[x] - a[x]) * (c[y] - a[y]) > (b[y] - a[y]) * (c[x] - a[x]) end function function convex_hull(sequence points) sequence h = {} points = sort(deep_copy(points)) /* lower hull */ for i=1 to length(points) do while length(h)>=2 and not ccw(h[$-1], h[$], points[i]) do h = h[1..$-1] end while h = append(h, points[i]) end for /* upper hull */ integer t = length(h)+1 for i=length(points) to 1 by -1 do while length(h)>=t and not ccw(h[$-1],h[$],points[i]) do h = h[1..$-1] end while h = append(h, points[i]) end for h = h[1..$-1] return h end function for i=1 to length(tests) do printf(1,"For test set: ") pp(tests[i],{pp_Indent,13,pp_Maxlen,111}) printf(1,"Convex Hull is: ") pp(convex_hull(tests[i])) end for -- plots the test points in red crosses and the convex hull in green circles include pGUI.e include IupGraph.e Ihandle dlg, graph function get_data(Ihandle /*graph*/) IupSetStrAttribute(graph, "GTITLE", "Marks Mode (%d/%d)", {t, length(tests)}) sequence tt = tests[t], {x,y} = columnize(tt), {cx,cy} = columnize(convex_hull(tt)) -- and close the loop: cx &= cx[1] cy &= cy[1] return {{x,y,CD_RED}, {cx,cy,CD_GREEN,"HOLLOW_CIRCLE","MARKLINE"}} end function function key_cb(Ihandle /*ih*/, atom c) if c=K_ESC then return IUP_CLOSE end if -- (standard practice for me) if c=K_F5 then return IUP_DEFAULT end if -- (let browser reload work) if c=K_LEFT then t = iff(t=1?length(tests):t-1) end if if c=K_RIGHT then t = iff(t=length(tests)?1:t+1) end if IupUpdate(graph) return IUP_CONTINUE end function IupOpen() graph = IupGraph(get_data,"RASTERSIZE=640x480,MODE=MARK") dlg = IupDialog(graph,`TITLE="Convex Hull",MINSIZE=270x430`) IupSetAttributes(graph,"XTICK=2,XMIN=-12,XMAX=20,XMARGIN=25,YTICK=2,YMIN=-12,YMAX=20") IupSetInt(graph,"GRIDCOLOR",CD_LIGHT_GREY) IupShow(dlg) IupSetCallback(dlg, "K_ANY", Icallback("key_cb")) IupSetAttribute(graph,`RASTERSIZE`,NULL) if platform()!=JS then IupMainLoop() IupClose() end if
http://rosettacode.org/wiki/Convert_seconds_to_compound_duration
Convert seconds to compound duration
Task Write a function or program which:   takes a positive integer representing a duration in seconds as input (e.g., 100), and   returns a string which shows the same duration decomposed into:   weeks,   days,   hours,   minutes,   and   seconds. This is detailed below (e.g., "2 hr, 59 sec"). Demonstrate that it passes the following three test-cases: Test Cases input number output string 7259 2 hr, 59 sec 86400 1 d 6000000 9 wk, 6 d, 10 hr, 40 min Details The following five units should be used: unit suffix used in output conversion week wk 1 week = 7 days day d 1 day = 24 hours hour hr 1 hour = 60 minutes minute min 1 minute = 60 seconds second sec However, only include quantities with non-zero values in the output (e.g., return "1 d" and not "0 wk, 1 d, 0 hr, 0 min, 0 sec"). Give larger units precedence over smaller ones as much as possible (e.g., return 2 min, 10 sec and not 1 min, 70 sec or 130 sec) Mimic the formatting shown in the test-cases (quantities sorted from largest unit to smallest and separated by comma+space; value and unit of each quantity separated by space).
#REXX
REXX
/* REXX --------------------------------------------------------------- * Format seconds into a time string *--------------------------------------------------------------------*/ Call test 7259 ,'2 hr, 59 sec' Call test 86400 ,'1 d' Call test 6000000 ,'9 wk, 6 d, 10 hr, 40 min' Call test 123.50 ,'2 min, 3.5 sec' Call test 123.00 ,'2 min, 3 sec' Call test 0.00 ,'0 sec' Exit   test: Parse arg secs,xres res=sec2ct(secs) Say res If res<>xres Then Say '**ERROR**' Return   sec2ct: Parse Arg s /* m=s%60; s=s//60 h=m%60; m=m//60 d=h%24; h=h//24 w=d%7; d=d//7 */ If s=0 Then Return '0 sec' Parse Value split(s,60) with m s Parse Value split(m,60) with h m Parse Value split(h,24) with d h Parse Value split(d, 7) with w d ol='' If w>0 Then ol=ol w 'wk,' If d>0 Then ol=ol d 'd,' If h>0 Then ol=ol h 'hr,' If m>0 Then ol=ol m 'min,' If s>0 Then ol=ol (s/1) 'sec' ol=strip(ol) ol=strip(ol,,',') Return ol   split: Procedure Parse Arg what,how a=what%how b=what//how Return a b
http://rosettacode.org/wiki/Concurrent_computing
Concurrent computing
Task Using either native language concurrency syntax or freely available libraries, write a program to display the strings "Enjoy" "Rosetta" "Code", one string per line, in random order. Concurrency syntax must use threads, tasks, co-routines, or whatever concurrency is called in your language.
#FreeBASIC
FreeBASIC
' FB 1.05.0 Win64 ' Compiled with -mt switch (to use threadsafe runtiume) ' The 'ThreadCall' functionality in FB is based internally on LibFFi (see [https://github.com/libffi/libffi/blob/master/LICENSE] for license)   Sub thread1() Print "Enjoy" End Sub   Sub thread2() Print "Rosetta" End Sub   Sub thread3() Print "Code" End Sub   Print "Press any key to print next batch of 3 strings or ESC to quit" Print   Do Dim t1 As Any Ptr = ThreadCall thread1 Dim t2 As Any Ptr = ThreadCall thread2 Dim t3 As Any Ptr = ThreadCall thread3 ThreadWait t1 ThreadWait t2 ThreadWait t3 Print Sleep Loop While Inkey <> Chr(27)
http://rosettacode.org/wiki/Concurrent_computing
Concurrent computing
Task Using either native language concurrency syntax or freely available libraries, write a program to display the strings "Enjoy" "Rosetta" "Code", one string per line, in random order. Concurrency syntax must use threads, tasks, co-routines, or whatever concurrency is called in your language.
#Go
Go
package main   import ( "fmt" "golang.org/x/exp/rand" "time" )   func main() { words := []string{"Enjoy", "Rosetta", "Code"} seed := uint64(time.Now().UnixNano()) q := make(chan string) for i, w := range words { go func(w string, seed uint64) { r := rand.New(rand.NewSource(seed)) time.Sleep(time.Duration(r.Int63n(1e9))) q <- w }(w, seed+uint64(i)) } for i := 0; i < len(words); i++ { fmt.Println(<-q) } }
http://rosettacode.org/wiki/Conjugate_transpose
Conjugate transpose
Suppose that a matrix M {\displaystyle M} contains complex numbers. Then the conjugate transpose of M {\displaystyle M} is a matrix M H {\displaystyle M^{H}} containing the complex conjugates of the matrix transposition of M {\displaystyle M} . ( M H ) j i = M i j ¯ {\displaystyle (M^{H})_{ji}={\overline {M_{ij}}}} This means that row j {\displaystyle j} , column i {\displaystyle i} of the conjugate transpose equals the complex conjugate of row i {\displaystyle i} , column j {\displaystyle j} of the original matrix. In the next list, M {\displaystyle M} must also be a square matrix. A Hermitian matrix equals its own conjugate transpose: M H = M {\displaystyle M^{H}=M} . A normal matrix is commutative in multiplication with its conjugate transpose: M H M = M M H {\displaystyle M^{H}M=MM^{H}} . A unitary matrix has its inverse equal to its conjugate transpose: M H = M − 1 {\displaystyle M^{H}=M^{-1}} . This is true iff M H M = I n {\displaystyle M^{H}M=I_{n}} and iff M M H = I n {\displaystyle MM^{H}=I_{n}} , where I n {\displaystyle I_{n}} is the identity matrix. Task Given some matrix of complex numbers, find its conjugate transpose. Also determine if the matrix is a: Hermitian matrix, normal matrix, or unitary matrix. See also MathWorld entry: conjugate transpose MathWorld entry: Hermitian matrix MathWorld entry: normal matrix MathWorld entry: unitary matrix
#Racket
Racket
  #lang racket (require math) (define H matrix-hermitian)   (define (normal? M) (define MH (H M)) (equal? (matrix* MH M) (matrix* M MH)))   (define (unitary? M) (define MH (H M)) (and (matrix-identity? (matrix* MH M)) (matrix-identity? (matrix* M MH))))   (define (hermitian? M) (equal? (H M) M))  
http://rosettacode.org/wiki/Conjugate_transpose
Conjugate transpose
Suppose that a matrix M {\displaystyle M} contains complex numbers. Then the conjugate transpose of M {\displaystyle M} is a matrix M H {\displaystyle M^{H}} containing the complex conjugates of the matrix transposition of M {\displaystyle M} . ( M H ) j i = M i j ¯ {\displaystyle (M^{H})_{ji}={\overline {M_{ij}}}} This means that row j {\displaystyle j} , column i {\displaystyle i} of the conjugate transpose equals the complex conjugate of row i {\displaystyle i} , column j {\displaystyle j} of the original matrix. In the next list, M {\displaystyle M} must also be a square matrix. A Hermitian matrix equals its own conjugate transpose: M H = M {\displaystyle M^{H}=M} . A normal matrix is commutative in multiplication with its conjugate transpose: M H M = M M H {\displaystyle M^{H}M=MM^{H}} . A unitary matrix has its inverse equal to its conjugate transpose: M H = M − 1 {\displaystyle M^{H}=M^{-1}} . This is true iff M H M = I n {\displaystyle M^{H}M=I_{n}} and iff M M H = I n {\displaystyle MM^{H}=I_{n}} , where I n {\displaystyle I_{n}} is the identity matrix. Task Given some matrix of complex numbers, find its conjugate transpose. Also determine if the matrix is a: Hermitian matrix, normal matrix, or unitary matrix. See also MathWorld entry: conjugate transpose MathWorld entry: Hermitian matrix MathWorld entry: normal matrix MathWorld entry: unitary matrix
#Raku
Raku
for [ # Test Matrices [ 1, 1+i, 2i], [ 1-i, 5, -3], [0-2i, -3, 0] ], [ [1, 1, 0], [0, 1, 1], [1, 0, 1] ], [ [0.707 , 0.707, 0], [0.707i, 0-0.707i, 0], [0 , 0, i] ] -> @m { say "\nMatrix:"; @m.&say-it; my @t = @m».conj.&mat-trans; say "\nTranspose:"; @t.&say-it; say "Is Hermitian?\t{is-Hermitian(@m, @t)}"; say "Is Normal?\t{is-Normal(@m, @t)}"; say "Is Unitary?\t{is-Unitary(@m, @t)}"; }   sub is-Hermitian (@m, @t, --> Bool) { so @m».Complex eqv @t».Complex }   sub is-Normal (@m, @t, --> Bool) { so mat-mult(@m, @t)».Complex eqv mat-mult(@t, @m)».Complex }   sub is-Unitary (@m, @t, --> Bool) { so mat-mult(@m, @t, 1e-3)».Complex eqv mat-ident(+@m)».Complex; }   sub mat-trans (@m) { map { [ @m[*;$_] ] }, ^@m[0] }   sub mat-ident ($n) { [ map { [ flat 0 xx $_, 1, 0 xx $n - 1 - $_ ] }, ^$n ] }   sub mat-mult (@a, @b, \ε = 1e-15) { my @p; for ^@a X ^@b[0] -> ($r, $c) { @p[$r][$c] += @a[$r][$_] * @b[$_][$c] for ^@b; @p[$r][$c].=round(ε); # avoid floating point math errors } @p }   sub say-it (@array) { $_».fmt("%9s").say for @array }
http://rosettacode.org/wiki/Compound_data_type
Compound data type
Data Structure This illustrates a data structure, a means of storing data within a program. You may see other such structures in the Data Structures category. Task Create a compound data type: Point(x,y) A compound data type is one that holds multiple independent values. Related task   Enumeration See also Array Associative array: Creation, Iteration Collections Compound data type Doubly-linked list: Definition, Element definition, Element insertion, List Traversal, Element Removal Linked list Queue: Definition, Usage Set Singly-linked list: Element definition, Element insertion, List Traversal, Element Removal Stack
#EchoLisp
EchoLisp
  (lib 'struct) (struct Point (x y)) (Point 3 4) → #<Point> (3 4)   ;; run-time type checking is possible (lib 'types) (struct Point (x y)) (struct-type Point Number Number) (Point 3 4) (Point 3 'albert) ❌ error: #number? : type-check failure : albert → 'Point:y'  
http://rosettacode.org/wiki/Compound_data_type
Compound data type
Data Structure This illustrates a data structure, a means of storing data within a program. You may see other such structures in the Data Structures category. Task Create a compound data type: Point(x,y) A compound data type is one that holds multiple independent values. Related task   Enumeration See also Array Associative array: Creation, Iteration Collections Compound data type Doubly-linked list: Definition, Element definition, Element insertion, List Traversal, Element Removal Linked list Queue: Definition, Usage Set Singly-linked list: Element definition, Element insertion, List Traversal, Element Removal Stack
#Ela
Ela
type Maybe = None | Some a
http://rosettacode.org/wiki/Continued_fraction
Continued fraction
continued fraction Mathworld a 0 + b 1 a 1 + b 2 a 2 + b 3 a 3 + ⋱ {\displaystyle a_{0}+{\cfrac {b_{1}}{a_{1}+{\cfrac {b_{2}}{a_{2}+{\cfrac {b_{3}}{a_{3}+\ddots }}}}}}} The task is to write a program which generates such a number and prints a real representation of it. The code should be tested by calculating and printing the square root of 2, Napier's Constant, and Pi, using the following coefficients: For the square root of 2, use a 0 = 1 {\displaystyle a_{0}=1} then a N = 2 {\displaystyle a_{N}=2} . b N {\displaystyle b_{N}} is always 1 {\displaystyle 1} . 2 = 1 + 1 2 + 1 2 + 1 2 + ⋱ {\displaystyle {\sqrt {2}}=1+{\cfrac {1}{2+{\cfrac {1}{2+{\cfrac {1}{2+\ddots }}}}}}} For Napier's Constant, use a 0 = 2 {\displaystyle a_{0}=2} , then a N = N {\displaystyle a_{N}=N} . b 1 = 1 {\displaystyle b_{1}=1} then b N = N − 1 {\displaystyle b_{N}=N-1} . e = 2 + 1 1 + 1 2 + 2 3 + 3 4 + ⋱ {\displaystyle e=2+{\cfrac {1}{1+{\cfrac {1}{2+{\cfrac {2}{3+{\cfrac {3}{4+\ddots }}}}}}}}} For Pi, use a 0 = 3 {\displaystyle a_{0}=3} then a N = 6 {\displaystyle a_{N}=6} . b N = ( 2 N − 1 ) 2 {\displaystyle b_{N}=(2N-1)^{2}} . π = 3 + 1 6 + 9 6 + 25 6 + ⋱ {\displaystyle \pi =3+{\cfrac {1}{6+{\cfrac {9}{6+{\cfrac {25}{6+\ddots }}}}}}} See also   Continued fraction/Arithmetic for tasks that do arithmetic over continued fractions.
#REXX
REXX
/*REXX program calculates and displays values of various continued fractions. */ parse arg terms digs . if terms=='' | terms=="," then terms=500 if digs=='' | digs=="," then digs=100 numeric digits digs /*use 100 decimal digits for display.*/ b.=1 /*omitted ß terms are assumed to be 1.*/ /*══════════════════════════════════════════════════════════════════════════════════════*/ a.=2; call tell '√2', cf(1) /*══════════════════════════════════════════════════════════════════════════════════════*/ a.=1; do N=2 by 2 to terms; a.N=2; end; call tell '√3', cf(1) /*also: 2∙sin(π/3) */ /*══════════════════════════════════════════════════════════════════════════════════════*/ a.=2 /* ___ */ do N=2 to 17 /*generalized √ N */ b.=N-1; NN=right(N, 2); call tell 'gen √'NN, cf(1) end /*N*/ /*══════════════════════════════════════════════════════════════════════════════════════*/ a.=2; b.=-1/2; call tell 'gen √ ½', cf(1) /*══════════════════════════════════════════════════════════════════════════════════════*/ do j=1 for terms; a.j=j; if j>1 then b.j=a.p; p=j; end; call tell 'e', cf(2) /*══════════════════════════════════════════════════════════════════════════════════════*/ a.=1; call tell 'φ, phi', cf(1) /*══════════════════════════════════════════════════════════════════════════════════════*/ a.=1; do j=1 for terms; if j//2 then a.j=j; end; call tell 'tan(1)', cf(1) /*══════════════════════════════════════════════════════════════════════════════════════*/ do j=1 for terms; a.j=2*j+1; end; call tell 'coth(1)', cf(1) /*══════════════════════════════════════════════════════════════════════════════════════*/ do j=1 for terms; a.j=4*j+2; end; call tell 'coth(½)', cf(2) /*also: [e+1]÷[e-1] */ /*══════════════════════════════════════════════════════════════════════════════════════*/ terms=100000 a.=6; do j=1 for terms; b.j=(2*j-1)**2; end; call tell 'π, pi', cf(3) exit /*stick a fork in it, we're all done. */ /*──────────────────────────────────────────────────────────────────────────────────────*/ cf: procedure expose a. b. terms; parse arg C;  !=0; numeric digits 9+digits() do k=terms by -1 for terms; d=a.k+!;  !=b.k/d end /*k*/ return !+C /*──────────────────────────────────────────────────────────────────────────────────────*/ tell: parse arg ?,v; $=left(format(v)/1,1+digits()); w=50 /*50 bytes of terms*/ aT=; do k=1; _=space(aT a.k); if length(_)>w then leave; aT=_; end /*k*/ bT=; do k=1; _=space(bT b.k); if length(_)>w then leave; bT=_; end /*k*/ say right(?,8) "=" $ ' α terms='aT ... if b.1\==1 then say right("",12+digits()) ' ß terms='bT ... a=; b.=1; return /*only 50 bytes of α & ß terms ↑ are displayed. */
http://rosettacode.org/wiki/Copy_a_string
Copy a string
This task is about copying a string. Task Where it is relevant, distinguish between copying the contents of a string versus making an additional reference to an existing string. Other tasks related to string operations: Metrics Array length String length Copy a string Empty string  (assignment) Counting Word frequency Letter frequency Jewels and stones I before E except after C Bioinformatics/base count Count occurrences of a substring Count how many vowels and consonants occur in a string Remove/replace XXXX redacted Conjugate a Latin verb Remove vowels from a string String interpolation (included) Strip block comments Strip comments from a string Strip a set of characters from a string Strip whitespace from a string -- top and tail Strip control codes and extended characters from a string Anagrams/Derangements/shuffling Word wheel ABC problem Sattolo cycle Knuth shuffle Ordered words Superpermutation minimisation Textonyms (using a phone text pad) Anagrams Anagrams/Deranged anagrams Permutations/Derangements Find/Search/Determine ABC words Odd words Word ladder Semordnilap Word search Wordiff  (game) String matching Tea cup rim text Alternade words Changeable words State name puzzle String comparison Unique characters Unique characters in each string Extract file extension Levenshtein distance Palindrome detection Common list elements Longest common suffix Longest common prefix Compare a list of strings Longest common substring Find common directory path Words from neighbour ones Change e letters to i in words Non-continuous subsequences Longest common subsequence Longest palindromic substrings Longest increasing subsequence Words containing "the" substring Sum of the digits of n is substring of n Determine if a string is numeric Determine if a string is collapsible Determine if a string is squeezable Determine if a string has all unique characters Determine if a string has all the same characters Longest substrings without repeating characters Find words which contains all the vowels Find words which contains most consonants Find words which contains more than 3 vowels Find words which first and last three letters are equals Find words which odd letters are consonants and even letters are vowels or vice_versa Formatting Substring Rep-string Word wrap String case Align columns Literals/String Repeat a string Brace expansion Brace expansion using ranges Reverse a string Phrase reversals Comma quibbling Special characters String concatenation Substring/Top and tail Commatizing numbers Reverse words in a string Suffixation of decimal numbers Long literals, with continuations Numerical and alphabetical suffixes Abbreviations, easy Abbreviations, simple Abbreviations, automatic Song lyrics/poems/Mad Libs/phrases Mad Libs Magic 8-ball 99 Bottles of Beer The Name Game (a song) The Old lady swallowed a fly The Twelve Days of Christmas Tokenize Text between Tokenize a string Word break problem Tokenize a string with escaping Split a character string based on change of character Sequences Show ASCII table De Bruijn sequences Self-referential sequences Generate lower case ASCII alphabet
#Perl
Perl
my $original = 'Hello.'; my $new = $original; $new = 'Goodbye.'; print "$original\n"; # prints "Hello."
http://rosettacode.org/wiki/Copy_a_string
Copy a string
This task is about copying a string. Task Where it is relevant, distinguish between copying the contents of a string versus making an additional reference to an existing string. Other tasks related to string operations: Metrics Array length String length Copy a string Empty string  (assignment) Counting Word frequency Letter frequency Jewels and stones I before E except after C Bioinformatics/base count Count occurrences of a substring Count how many vowels and consonants occur in a string Remove/replace XXXX redacted Conjugate a Latin verb Remove vowels from a string String interpolation (included) Strip block comments Strip comments from a string Strip a set of characters from a string Strip whitespace from a string -- top and tail Strip control codes and extended characters from a string Anagrams/Derangements/shuffling Word wheel ABC problem Sattolo cycle Knuth shuffle Ordered words Superpermutation minimisation Textonyms (using a phone text pad) Anagrams Anagrams/Deranged anagrams Permutations/Derangements Find/Search/Determine ABC words Odd words Word ladder Semordnilap Word search Wordiff  (game) String matching Tea cup rim text Alternade words Changeable words State name puzzle String comparison Unique characters Unique characters in each string Extract file extension Levenshtein distance Palindrome detection Common list elements Longest common suffix Longest common prefix Compare a list of strings Longest common substring Find common directory path Words from neighbour ones Change e letters to i in words Non-continuous subsequences Longest common subsequence Longest palindromic substrings Longest increasing subsequence Words containing "the" substring Sum of the digits of n is substring of n Determine if a string is numeric Determine if a string is collapsible Determine if a string is squeezable Determine if a string has all unique characters Determine if a string has all the same characters Longest substrings without repeating characters Find words which contains all the vowels Find words which contains most consonants Find words which contains more than 3 vowels Find words which first and last three letters are equals Find words which odd letters are consonants and even letters are vowels or vice_versa Formatting Substring Rep-string Word wrap String case Align columns Literals/String Repeat a string Brace expansion Brace expansion using ranges Reverse a string Phrase reversals Comma quibbling Special characters String concatenation Substring/Top and tail Commatizing numbers Reverse words in a string Suffixation of decimal numbers Long literals, with continuations Numerical and alphabetical suffixes Abbreviations, easy Abbreviations, simple Abbreviations, automatic Song lyrics/poems/Mad Libs/phrases Mad Libs Magic 8-ball 99 Bottles of Beer The Name Game (a song) The Old lady swallowed a fly The Twelve Days of Christmas Tokenize Text between Tokenize a string Word break problem Tokenize a string with escaping Split a character string based on change of character Sequences Show ASCII table De Bruijn sequences Self-referential sequences Generate lower case ASCII alphabet
#Phix
Phix
string one = "feed" string two = one -- (two becomes "feed", one remains "feed") two[2..3] = "oo" -- (two becomes "food", one remains "feed") one[1] = 'n' -- (two remains "food", one becomes "need") ?{one,two}
http://rosettacode.org/wiki/Constrained_random_points_on_a_circle
Constrained random points on a circle
Task Generate 100 <x,y> coordinate pairs such that x and y are integers sampled from the uniform distribution with the condition that 10 ≤ x 2 + y 2 ≤ 15 {\displaystyle 10\leq {\sqrt {x^{2}+y^{2}}}\leq 15} . Then display/plot them. The outcome should be a "fuzzy" circle. The actual number of points plotted may be less than 100, given that some pairs may be generated more than once. There are several possible approaches to accomplish this. Here are two possible algorithms. 1) Generate random pairs of integers and filter out those that don't satisfy this condition: 10 ≤ x 2 + y 2 ≤ 15 {\displaystyle 10\leq {\sqrt {x^{2}+y^{2}}}\leq 15} . 2) Precalculate the set of all possible points (there are 404 of them) and select randomly from this set.
#Liberty_BASIC
Liberty BASIC
' RC Constrained Random Points on a Circle   nomainwin   WindowWidth =400 WindowHeight =430   open "Constrained Random Points on a Circle" for graphics_nsb as #w   #w "trapclose [quit]" #w "down ; size 7 ; color red ; fill black"   for i =1 to 1000 do x =int( 30 *rnd( 1)) -15 y =int( 30 *rnd( 1)) -15 loop until IsInRange( x, y) =1 #w "set "; 200 +10 *x; " "; 200 - 10 *y next   wait   function IsInRange( x, y) z =sqr( x*x +y*y) if 10 <=z and z <=15 then IsInRange =1 else IsInRange =0 end function   [quit] close #w end
http://rosettacode.org/wiki/Convex_hull
Convex hull
Find the points which form a convex hull from a set of arbitrary two dimensional points. For example, given the points (16,3), (12,17), (0,6), (-4,-6), (16,6), (16,-7), (16,-3), (17,-4), (5,19), (19,-8), (3,16), (12,13), (3,-4), (17,5), (-3,15), (-3,-9), (0,11), (-9,-3), (-4,-2) and (12,10) the convex hull would be (-9,-3), (-3,-9), (19,-8), (17,5), (12,17), (5,19) and (-3,15). See also Convex Hull (youtube) http://www.geeksforgeeks.org/convex-hull-set-2-graham-scan/
#Python
Python
from __future__ import print_function from shapely.geometry import MultiPoint   if __name__=="__main__": pts = MultiPoint([(16,3), (12,17), (0,6), (-4,-6), (16,6), (16,-7), (16,-3), (17,-4), (5,19), (19,-8), (3,16), (12,13), (3,-4), (17,5), (-3,15), (-3,-9), (0,11), (-9,-3), (-4,-2), (12,10)]) print (pts.convex_hull)
http://rosettacode.org/wiki/Convert_seconds_to_compound_duration
Convert seconds to compound duration
Task Write a function or program which:   takes a positive integer representing a duration in seconds as input (e.g., 100), and   returns a string which shows the same duration decomposed into:   weeks,   days,   hours,   minutes,   and   seconds. This is detailed below (e.g., "2 hr, 59 sec"). Demonstrate that it passes the following three test-cases: Test Cases input number output string 7259 2 hr, 59 sec 86400 1 d 6000000 9 wk, 6 d, 10 hr, 40 min Details The following five units should be used: unit suffix used in output conversion week wk 1 week = 7 days day d 1 day = 24 hours hour hr 1 hour = 60 minutes minute min 1 minute = 60 seconds second sec However, only include quantities with non-zero values in the output (e.g., return "1 d" and not "0 wk, 1 d, 0 hr, 0 min, 0 sec"). Give larger units precedence over smaller ones as much as possible (e.g., return 2 min, 10 sec and not 1 min, 70 sec or 130 sec) Mimic the formatting shown in the test-cases (quantities sorted from largest unit to smallest and separated by comma+space; value and unit of each quantity separated by space).
#Ring
Ring
  sec = 6000005 week = floor(sec/60/60/24/7) if week > 0 see sec see " seconds is " + week + " weeks " ok day = floor(sec/60/60/24) % 7 if day > 0 see day see " days " ok hour = floor(sec/60/60) % 24 if hour > 0 see hour see " hours " ok minute = floor(sec/60) % 60 if minute > 0 see minute see " minutes " ok second = sec % 60 if second > 0 see second see " seconds" + nl ok  
http://rosettacode.org/wiki/Concurrent_computing
Concurrent computing
Task Using either native language concurrency syntax or freely available libraries, write a program to display the strings "Enjoy" "Rosetta" "Code", one string per line, in random order. Concurrency syntax must use threads, tasks, co-routines, or whatever concurrency is called in your language.
#Groovy
Groovy
'Enjoy Rosetta Code'.tokenize().collect { w -> Thread.start { Thread.sleep(1000 * Math.random() as int) println w } }.each { it.join() }
http://rosettacode.org/wiki/Concurrent_computing
Concurrent computing
Task Using either native language concurrency syntax or freely available libraries, write a program to display the strings "Enjoy" "Rosetta" "Code", one string per line, in random order. Concurrency syntax must use threads, tasks, co-routines, or whatever concurrency is called in your language.
#Haskell
Haskell
import Control.Concurrent   main = mapM_ forkIO [process1, process2, process3] where process1 = putStrLn "Enjoy" process2 = putStrLn "Rosetta" process3 = putStrLn "Code"
http://rosettacode.org/wiki/Conjugate_transpose
Conjugate transpose
Suppose that a matrix M {\displaystyle M} contains complex numbers. Then the conjugate transpose of M {\displaystyle M} is a matrix M H {\displaystyle M^{H}} containing the complex conjugates of the matrix transposition of M {\displaystyle M} . ( M H ) j i = M i j ¯ {\displaystyle (M^{H})_{ji}={\overline {M_{ij}}}} This means that row j {\displaystyle j} , column i {\displaystyle i} of the conjugate transpose equals the complex conjugate of row i {\displaystyle i} , column j {\displaystyle j} of the original matrix. In the next list, M {\displaystyle M} must also be a square matrix. A Hermitian matrix equals its own conjugate transpose: M H = M {\displaystyle M^{H}=M} . A normal matrix is commutative in multiplication with its conjugate transpose: M H M = M M H {\displaystyle M^{H}M=MM^{H}} . A unitary matrix has its inverse equal to its conjugate transpose: M H = M − 1 {\displaystyle M^{H}=M^{-1}} . This is true iff M H M = I n {\displaystyle M^{H}M=I_{n}} and iff M M H = I n {\displaystyle MM^{H}=I_{n}} , where I n {\displaystyle I_{n}} is the identity matrix. Task Given some matrix of complex numbers, find its conjugate transpose. Also determine if the matrix is a: Hermitian matrix, normal matrix, or unitary matrix. See also MathWorld entry: conjugate transpose MathWorld entry: Hermitian matrix MathWorld entry: normal matrix MathWorld entry: unitary matrix
#REXX
REXX
/*REXX program performs a conjugate transpose on a complex square matrix. */ parse arg N elements; if N==''|N=="," then N=3 /*Not specified? Then use the default.*/ k= 0; do r=1 for N do c=1 for N; k= k+1; M.r.c= word( word(elements, k) 1, 1) end /*c*/ end /*r*/ call showCmat 'M' ,N /*display a nicely formatted matrix. */ identity.= 0; do d=1 for N; identity.d.d= 1; end /*d*/ call conjCmat 'MH', "M" ,N /*conjugate the M matrix ───► MH */ call showCmat 'MH' ,N /*display a nicely formatted matrix. */ say 'M is Hermitian: ' word('no yes', isHermitian('M', "MH", N) + 1) call multCmat 'M', 'MH', 'MMH', N /*multiple the two matrices together. */ call multCmat 'MH', 'M', 'MHM', N /* " " " " " */ say ' M is Normal: ' word('no yes', isHermitian('MMH', "MHM", N) + 1) say ' M is Unary: ' word('no yes', isUnary('M', N) + 1) say 'MMH is Unary: ' word('no yes', isUnary('MMH', N) + 1) say 'MHM is Unary: ' word('no yes', isUnary('MHM', N) + 1) exit /*stick a fork in it, we're all done. */ /*──────────────────────────────────────────────────────────────────────────────────────*/ cP: procedure; arg ',' c; return word( strip( translate(c, , 'IJ') ) 0, 1) rP: procedure; parse arg r ','; return word( r 0, 1) /*◄──maybe return a 0 ↑ */ /*──────────────────────────────────────────────────────────────────────────────────────*/ conjCmat: parse arg matX,matY,rows 1 cols; call normCmat matY, rows do r=1 for rows; _= do c=1 for cols; v= value(matY'.'r"."c) rP= rP(v); cP= -cP(v); call value matX'.'c"."r, rP','cP end /*c*/ end /*r*/; return /*──────────────────────────────────────────────────────────────────────────────────────*/ isHermitian: parse arg matX,matY,rows 1 cols; call normCmat matX, rows call normCmat matY, rows do r=1 for rows; _= do c=1 for cols if value(matX'.'r"."c) \= value(matY'.'r"."c) then return 0 end /*c*/ end /*r*/; return 1 /*──────────────────────────────────────────────────────────────────────────────────────*/ isUnary: parse arg matX,rows 1 cols do r=1 for rows; _= do c=1 for cols; z= value(matX'.'r"."c); rP= rP(z); cP= cP(z) if abs( sqrt( rP(z) **2 + cP(z)**2) - (r==c)) >= .0001 then return 0 end /*c*/ end /*r*/; return 1 /*──────────────────────────────────────────────────────────────────────────────────────*/ multCmat: parse arg matA,matB,matT,rows 1 cols; call value matT'.', 0 do r=1 for rows; _= do c=1 for cols do k=1 for cols; T= value(matT'.'r"."c); Tr= rP(T); Tc= cP(T) A= value(matA'.'r"."k); Ar= rP(A); Ac= cP(A) B= value(matB'.'k"."c); Br= rP(B); Bc= cP(B) Pr= Ar*Br - Ac*Bc; Pc= Ac*Br + Ar*Bc; Tr= Tr+Pr; Tc= Tc+Pc call value matT'.'r"."c,Tr','Tc end /*k*/ end /*c*/ end /*r*/; return /*──────────────────────────────────────────────────────────────────────────────────────*/ normCmat: parse arg matN,rows 1 cols do r=1 to rows; _= do c=1 to cols; v= translate( value(matN'.'r"."c), , "IiJj") parse upper var v real ',' cplx if real\=='' then real= real / 1 if cplx\=='' then cplx= cplx / 1; if cplx=0 then cplx= if cplx\=='' then cplx= cplx"j" call value matN'.'r"."c, strip(real','cplx, "T", ',') end /*c*/ end /*r*/; return /*──────────────────────────────────────────────────────────────────────────────────────*/ showCmat: parse arg matX,rows,cols; if cols=='' then cols= rows; @@= left('', 6) say; say center('matrix' matX, 79, '─'); call normCmat matX, rows, cols do r=1 to rows; _= do c=1 to cols; _= _ @@ left( value(matX'.'r"."c), 9) end /*c*/ say _ end /*r*/; say; return /*──────────────────────────────────────────────────────────────────────────────────────*/ sqrt: procedure; parse arg x; if x=0 then return 0; d=digits(); numeric form; h=d+6 numeric digits; parse value format(x,2,1,,0) 'E0' with g 'E' _ .; g=g *.5'e'_ % 2 m.=9; do j=0 while h>9; m.j=h; h=h%2+1; end /*j*/ do k=j+5 to 0 by -1; numeric digits m.k; g=(g+x/g)*.5; end /*k*/; return g
http://rosettacode.org/wiki/Compound_data_type
Compound data type
Data Structure This illustrates a data structure, a means of storing data within a program. You may see other such structures in the Data Structures category. Task Create a compound data type: Point(x,y) A compound data type is one that holds multiple independent values. Related task   Enumeration See also Array Associative array: Creation, Iteration Collections Compound data type Doubly-linked list: Definition, Element definition, Element insertion, List Traversal, Element Removal Linked list Queue: Definition, Usage Set Singly-linked list: Element definition, Element insertion, List Traversal, Element Removal Stack
#Elena
Elena
struct Point { prop int X;   prop int Y;   constructor new(int x, int y) { X := x; Y := y } }
http://rosettacode.org/wiki/Compound_data_type
Compound data type
Data Structure This illustrates a data structure, a means of storing data within a program. You may see other such structures in the Data Structures category. Task Create a compound data type: Point(x,y) A compound data type is one that holds multiple independent values. Related task   Enumeration See also Array Associative array: Creation, Iteration Collections Compound data type Doubly-linked list: Definition, Element definition, Element insertion, List Traversal, Element Removal Linked list Queue: Definition, Usage Set Singly-linked list: Element definition, Element insertion, List Traversal, Element Removal Stack
#Elixir
Elixir
iex(1)> defmodule Point do ...(1)> defstruct x: 0, y: 0 ...(1)> end {:module, Point, <<70, 79, 82, ...>>, %Point{x: 0, y: 0}} iex(2)> origin = %Point{} %Point{x: 0, y: 0} iex(3)> pa = %Point{x: 10, y: 20} %Point{x: 10, y: 20} iex(4)> pa.x 10 iex(5)> %Point{pa | y: 30} %Point{x: 10, y: 30} iex(6)> %Point{x: px, y: py} = pa # pattern matching %Point{x: 10, y: 20} iex(7)> px 10 iex(8)> py 20
http://rosettacode.org/wiki/Continued_fraction
Continued fraction
continued fraction Mathworld a 0 + b 1 a 1 + b 2 a 2 + b 3 a 3 + ⋱ {\displaystyle a_{0}+{\cfrac {b_{1}}{a_{1}+{\cfrac {b_{2}}{a_{2}+{\cfrac {b_{3}}{a_{3}+\ddots }}}}}}} The task is to write a program which generates such a number and prints a real representation of it. The code should be tested by calculating and printing the square root of 2, Napier's Constant, and Pi, using the following coefficients: For the square root of 2, use a 0 = 1 {\displaystyle a_{0}=1} then a N = 2 {\displaystyle a_{N}=2} . b N {\displaystyle b_{N}} is always 1 {\displaystyle 1} . 2 = 1 + 1 2 + 1 2 + 1 2 + ⋱ {\displaystyle {\sqrt {2}}=1+{\cfrac {1}{2+{\cfrac {1}{2+{\cfrac {1}{2+\ddots }}}}}}} For Napier's Constant, use a 0 = 2 {\displaystyle a_{0}=2} , then a N = N {\displaystyle a_{N}=N} . b 1 = 1 {\displaystyle b_{1}=1} then b N = N − 1 {\displaystyle b_{N}=N-1} . e = 2 + 1 1 + 1 2 + 2 3 + 3 4 + ⋱ {\displaystyle e=2+{\cfrac {1}{1+{\cfrac {1}{2+{\cfrac {2}{3+{\cfrac {3}{4+\ddots }}}}}}}}} For Pi, use a 0 = 3 {\displaystyle a_{0}=3} then a N = 6 {\displaystyle a_{N}=6} . b N = ( 2 N − 1 ) 2 {\displaystyle b_{N}=(2N-1)^{2}} . π = 3 + 1 6 + 9 6 + 25 6 + ⋱ {\displaystyle \pi =3+{\cfrac {1}{6+{\cfrac {9}{6+{\cfrac {25}{6+\ddots }}}}}}} See also   Continued fraction/Arithmetic for tasks that do arithmetic over continued fractions.
#Ring
Ring
  # Project : Continued fraction   see "SQR(2) = " + contfrac(1, 1, "2", "1") + nl see " e = " + contfrac(2, 1, "n", "n") + nl see " PI = " + contfrac(3, 1, "6", "(2*n+1)^2") + nl   func contfrac(a0, b1, a, b) expr = "" n = 0 while len(expr) < (700 - n) n = n + 1 eval("temp1=" + a) eval("temp2=" + b) expr = expr + string(temp1) + char(43) + string(temp2) + "/(" end str = copy(")",n) eval("temp3=" + expr + "1" + str) return a0 + b1 / temp3  
http://rosettacode.org/wiki/Continued_fraction
Continued fraction
continued fraction Mathworld a 0 + b 1 a 1 + b 2 a 2 + b 3 a 3 + ⋱ {\displaystyle a_{0}+{\cfrac {b_{1}}{a_{1}+{\cfrac {b_{2}}{a_{2}+{\cfrac {b_{3}}{a_{3}+\ddots }}}}}}} The task is to write a program which generates such a number and prints a real representation of it. The code should be tested by calculating and printing the square root of 2, Napier's Constant, and Pi, using the following coefficients: For the square root of 2, use a 0 = 1 {\displaystyle a_{0}=1} then a N = 2 {\displaystyle a_{N}=2} . b N {\displaystyle b_{N}} is always 1 {\displaystyle 1} . 2 = 1 + 1 2 + 1 2 + 1 2 + ⋱ {\displaystyle {\sqrt {2}}=1+{\cfrac {1}{2+{\cfrac {1}{2+{\cfrac {1}{2+\ddots }}}}}}} For Napier's Constant, use a 0 = 2 {\displaystyle a_{0}=2} , then a N = N {\displaystyle a_{N}=N} . b 1 = 1 {\displaystyle b_{1}=1} then b N = N − 1 {\displaystyle b_{N}=N-1} . e = 2 + 1 1 + 1 2 + 2 3 + 3 4 + ⋱ {\displaystyle e=2+{\cfrac {1}{1+{\cfrac {1}{2+{\cfrac {2}{3+{\cfrac {3}{4+\ddots }}}}}}}}} For Pi, use a 0 = 3 {\displaystyle a_{0}=3} then a N = 6 {\displaystyle a_{N}=6} . b N = ( 2 N − 1 ) 2 {\displaystyle b_{N}=(2N-1)^{2}} . π = 3 + 1 6 + 9 6 + 25 6 + ⋱ {\displaystyle \pi =3+{\cfrac {1}{6+{\cfrac {9}{6+{\cfrac {25}{6+\ddots }}}}}}} See also   Continued fraction/Arithmetic for tasks that do arithmetic over continued fractions.
#Ruby
Ruby
require 'bigdecimal'   # square root of 2 sqrt2 = Object.new def sqrt2.a(n); n == 1 ? 1 : 2; end def sqrt2.b(n); 1; end   # Napier's constant napier = Object.new def napier.a(n); n == 1 ? 2 : n - 1; end def napier.b(n); n == 1 ? 1 : n - 1; end   pi = Object.new def pi.a(n); n == 1 ? 3 : 6; end def pi.b(n); (2*n - 1)**2; end   # Estimates the value of a continued fraction _cfrac_, to _prec_ # decimal digits of precision. Returns a BigDecimal. _cfrac_ must # respond to _cfrac.a(n)_ and _cfrac.b(n)_ for integer _n_ >= 1. def estimate(cfrac, prec) last_result = nil terms = prec   loop do # Estimate continued fraction for _n_ from 1 to _terms_. result = cfrac.a(terms) (terms - 1).downto(1) do |n| a = BigDecimal cfrac.a(n) b = BigDecimal cfrac.b(n) digits = [b.div(result, 1).exponent + prec, 1].max result = a + b.div(result, digits) end result = result.round(prec)   if result == last_result return result else # Double _terms_ and try again. last_result = result terms *= 2 end end end   puts estimate(sqrt2, 50).to_s('F') puts estimate(napier, 50).to_s('F') puts estimate(pi, 10).to_s('F')
http://rosettacode.org/wiki/Copy_a_string
Copy a string
This task is about copying a string. Task Where it is relevant, distinguish between copying the contents of a string versus making an additional reference to an existing string. Other tasks related to string operations: Metrics Array length String length Copy a string Empty string  (assignment) Counting Word frequency Letter frequency Jewels and stones I before E except after C Bioinformatics/base count Count occurrences of a substring Count how many vowels and consonants occur in a string Remove/replace XXXX redacted Conjugate a Latin verb Remove vowels from a string String interpolation (included) Strip block comments Strip comments from a string Strip a set of characters from a string Strip whitespace from a string -- top and tail Strip control codes and extended characters from a string Anagrams/Derangements/shuffling Word wheel ABC problem Sattolo cycle Knuth shuffle Ordered words Superpermutation minimisation Textonyms (using a phone text pad) Anagrams Anagrams/Deranged anagrams Permutations/Derangements Find/Search/Determine ABC words Odd words Word ladder Semordnilap Word search Wordiff  (game) String matching Tea cup rim text Alternade words Changeable words State name puzzle String comparison Unique characters Unique characters in each string Extract file extension Levenshtein distance Palindrome detection Common list elements Longest common suffix Longest common prefix Compare a list of strings Longest common substring Find common directory path Words from neighbour ones Change e letters to i in words Non-continuous subsequences Longest common subsequence Longest palindromic substrings Longest increasing subsequence Words containing "the" substring Sum of the digits of n is substring of n Determine if a string is numeric Determine if a string is collapsible Determine if a string is squeezable Determine if a string has all unique characters Determine if a string has all the same characters Longest substrings without repeating characters Find words which contains all the vowels Find words which contains most consonants Find words which contains more than 3 vowels Find words which first and last three letters are equals Find words which odd letters are consonants and even letters are vowels or vice_versa Formatting Substring Rep-string Word wrap String case Align columns Literals/String Repeat a string Brace expansion Brace expansion using ranges Reverse a string Phrase reversals Comma quibbling Special characters String concatenation Substring/Top and tail Commatizing numbers Reverse words in a string Suffixation of decimal numbers Long literals, with continuations Numerical and alphabetical suffixes Abbreviations, easy Abbreviations, simple Abbreviations, automatic Song lyrics/poems/Mad Libs/phrases Mad Libs Magic 8-ball 99 Bottles of Beer The Name Game (a song) The Old lady swallowed a fly The Twelve Days of Christmas Tokenize Text between Tokenize a string Word break problem Tokenize a string with escaping Split a character string based on change of character Sequences Show ASCII table De Bruijn sequences Self-referential sequences Generate lower case ASCII alphabet
#PHP
PHP
$src = "Hello"; $dst = $src;
http://rosettacode.org/wiki/Copy_a_string
Copy a string
This task is about copying a string. Task Where it is relevant, distinguish between copying the contents of a string versus making an additional reference to an existing string. Other tasks related to string operations: Metrics Array length String length Copy a string Empty string  (assignment) Counting Word frequency Letter frequency Jewels and stones I before E except after C Bioinformatics/base count Count occurrences of a substring Count how many vowels and consonants occur in a string Remove/replace XXXX redacted Conjugate a Latin verb Remove vowels from a string String interpolation (included) Strip block comments Strip comments from a string Strip a set of characters from a string Strip whitespace from a string -- top and tail Strip control codes and extended characters from a string Anagrams/Derangements/shuffling Word wheel ABC problem Sattolo cycle Knuth shuffle Ordered words Superpermutation minimisation Textonyms (using a phone text pad) Anagrams Anagrams/Deranged anagrams Permutations/Derangements Find/Search/Determine ABC words Odd words Word ladder Semordnilap Word search Wordiff  (game) String matching Tea cup rim text Alternade words Changeable words State name puzzle String comparison Unique characters Unique characters in each string Extract file extension Levenshtein distance Palindrome detection Common list elements Longest common suffix Longest common prefix Compare a list of strings Longest common substring Find common directory path Words from neighbour ones Change e letters to i in words Non-continuous subsequences Longest common subsequence Longest palindromic substrings Longest increasing subsequence Words containing "the" substring Sum of the digits of n is substring of n Determine if a string is numeric Determine if a string is collapsible Determine if a string is squeezable Determine if a string has all unique characters Determine if a string has all the same characters Longest substrings without repeating characters Find words which contains all the vowels Find words which contains most consonants Find words which contains more than 3 vowels Find words which first and last three letters are equals Find words which odd letters are consonants and even letters are vowels or vice_versa Formatting Substring Rep-string Word wrap String case Align columns Literals/String Repeat a string Brace expansion Brace expansion using ranges Reverse a string Phrase reversals Comma quibbling Special characters String concatenation Substring/Top and tail Commatizing numbers Reverse words in a string Suffixation of decimal numbers Long literals, with continuations Numerical and alphabetical suffixes Abbreviations, easy Abbreviations, simple Abbreviations, automatic Song lyrics/poems/Mad Libs/phrases Mad Libs Magic 8-ball 99 Bottles of Beer The Name Game (a song) The Old lady swallowed a fly The Twelve Days of Christmas Tokenize Text between Tokenize a string Word break problem Tokenize a string with escaping Split a character string based on change of character Sequences Show ASCII table De Bruijn sequences Self-referential sequences Generate lower case ASCII alphabet
#Picat
Picat
go => S1 = "string", println(s1=S1), S2 = S1, S2[1] := 'x', % also changes S1 println(s1=S1), println(s2=S2), nl,   S3 = "string", S4 = copy_term(S3), S4[1] := 'x', % no change of S3 println(s3=S3), println(s4=S4),   nl.
http://rosettacode.org/wiki/Constrained_random_points_on_a_circle
Constrained random points on a circle
Task Generate 100 <x,y> coordinate pairs such that x and y are integers sampled from the uniform distribution with the condition that 10 ≤ x 2 + y 2 ≤ 15 {\displaystyle 10\leq {\sqrt {x^{2}+y^{2}}}\leq 15} . Then display/plot them. The outcome should be a "fuzzy" circle. The actual number of points plotted may be less than 100, given that some pairs may be generated more than once. There are several possible approaches to accomplish this. Here are two possible algorithms. 1) Generate random pairs of integers and filter out those that don't satisfy this condition: 10 ≤ x 2 + y 2 ≤ 15 {\displaystyle 10\leq {\sqrt {x^{2}+y^{2}}}\leq 15} . 2) Precalculate the set of all possible points (there are 404 of them) and select randomly from this set.
#Locomotive_Basic
Locomotive Basic
10 MODE 1:RANDOMIZE TIME 20 FOR J=1 TO 100 30 X=INT(RND*30-15) 40 Y=INT(RND*30-15) 50 D=X*X+Y*Y 60 IF D<100 OR D>225 THEN GOTO 40 70 PLOT 320+10*X,200+10*Y:LOCATE 1,1:PRINT J 80 NEXT 90 CALL &BB06 ' wait for key press
http://rosettacode.org/wiki/Convex_hull
Convex hull
Find the points which form a convex hull from a set of arbitrary two dimensional points. For example, given the points (16,3), (12,17), (0,6), (-4,-6), (16,6), (16,-7), (16,-3), (17,-4), (5,19), (19,-8), (3,16), (12,13), (3,-4), (17,5), (-3,15), (-3,-9), (0,11), (-9,-3), (-4,-2) and (12,10) the convex hull would be (-9,-3), (-3,-9), (19,-8), (17,5), (12,17), (5,19) and (-3,15). See also Convex Hull (youtube) http://www.geeksforgeeks.org/convex-hull-set-2-graham-scan/
#Racket
Racket
#lang typed/racket (define-type Point (Pair Real Real)) (define-type Points (Listof Point))   (: ⊗ (Point Point Point -> Real)) (define/match (⊗ o a b) [((cons o.x o.y) (cons a.x a.y) (cons b.x b.y)) (- (* (- a.x o.x) (- b.y o.y)) (* (- a.y o.y) (- b.x o.x)))])   (: Point<? (Point Point -> Boolean)) (define (Point<? a b) (cond [(< (car a) (car b)) #t] [(> (car a) (car b)) #f] [else (< (cdr a) (cdr b))]))   ;; Input: a list P of points in the plane. (define (convex-hull [P:unsorted : Points])  ;; Sort the points of P by x-coordinate (in case of a tie, sort by y-coordinate). (define P (sort P:unsorted Point<?))  ;; for i = 1, 2, ..., n:  ;; while L contains at least two points and the sequence of last two points  ;; of L and the point P[i] does not make a counter-clockwise turn:  ;; remove the last point from L  ;; append P[i] to L  ;; TB: U is identical with (reverse P) (define (upper/lower-hull [P : Points]) (reverse (for/fold ((rev : Points null)) ((P.i (in-list P))) (let u/l : Points ((rev rev)) (match rev [(list p-2 p-1 ps ...) #:when (not (positive? (⊗ p-2 P.i p-1))) (u/l (list* p-1 ps))] [(list ps ...) (cons P.i ps)])))))    ;; Initialize U and L as empty lists.  ;; The lists will hold the vertices of upper and lower hulls respectively. (let ((U (upper/lower-hull (reverse P))) (L (upper/lower-hull P)))  ;; Remove the last point of each list (it's the same as the first point of the other list).  ;; Concatenate L and U to obtain the convex hull of P. (append (drop-right L 1) (drop-right U 1)))) ; Points in the result will be listed in CCW order.)   (module+ test (require typed/rackunit) (check-equal? (convex-hull (list '(16 . 3) '(12 . 17) '(0 . 6) '(-4 . -6) '(16 . 6) '(16 . -7) '(16 . -3) '(17 . -4) '(5 . 19) '(19 . -8) '(3 . 16) '(12 . 13) '(3 . -4) '(17 . 5) '(-3 . 15) '(-3 . -9) '(0 . 11) '(-9 . -3) '(-4 . -2) '(12 . 10))) (list '(-9 . -3) '(-3 . -9) '(19 . -8) '(17 . 5) '(12 . 17) '(5 . 19) '(-3 . 15))))
http://rosettacode.org/wiki/Convert_seconds_to_compound_duration
Convert seconds to compound duration
Task Write a function or program which:   takes a positive integer representing a duration in seconds as input (e.g., 100), and   returns a string which shows the same duration decomposed into:   weeks,   days,   hours,   minutes,   and   seconds. This is detailed below (e.g., "2 hr, 59 sec"). Demonstrate that it passes the following three test-cases: Test Cases input number output string 7259 2 hr, 59 sec 86400 1 d 6000000 9 wk, 6 d, 10 hr, 40 min Details The following five units should be used: unit suffix used in output conversion week wk 1 week = 7 days day d 1 day = 24 hours hour hr 1 hour = 60 minutes minute min 1 minute = 60 seconds second sec However, only include quantities with non-zero values in the output (e.g., return "1 d" and not "0 wk, 1 d, 0 hr, 0 min, 0 sec"). Give larger units precedence over smaller ones as much as possible (e.g., return 2 min, 10 sec and not 1 min, 70 sec or 130 sec) Mimic the formatting shown in the test-cases (quantities sorted from largest unit to smallest and separated by comma+space; value and unit of each quantity separated by space).
#Ruby
Ruby
MINUTE = 60 HOUR = MINUTE*60 DAY = HOUR*24 WEEK = DAY*7   def sec_to_str(sec) w, rem = sec.divmod(WEEK) d, rem = rem.divmod(DAY) h, rem = rem.divmod(HOUR) m, s = rem.divmod(MINUTE) units = ["#{w} wk", "#{d} d", "#{h} h", "#{m} min", "#{s} sec"] units.reject{|str| str.start_with?("0")}.join(", ") end   [7259, 86400, 6000000].each{|t| puts "#{t}\t: #{sec_to_str(t)}"}
http://rosettacode.org/wiki/Concurrent_computing
Concurrent computing
Task Using either native language concurrency syntax or freely available libraries, write a program to display the strings "Enjoy" "Rosetta" "Code", one string per line, in random order. Concurrency syntax must use threads, tasks, co-routines, or whatever concurrency is called in your language.
#Icon_and_Unicon
Icon and Unicon
procedure main() L:=[ thread write("Enjoy"), thread write("Rosetta"), thread write("Code") ] every wait(!L) end
http://rosettacode.org/wiki/Concurrent_computing
Concurrent computing
Task Using either native language concurrency syntax or freely available libraries, write a program to display the strings "Enjoy" "Rosetta" "Code", one string per line, in random order. Concurrency syntax must use threads, tasks, co-routines, or whatever concurrency is called in your language.
#J
J
smoutput&>({~?~@#);:'Enjoy Rosetta Code' Rosetta Code Enjoy
http://rosettacode.org/wiki/Compile-time_calculation
Compile-time calculation
Some programming languages allow calculation of values at compile time. Task Calculate   10!   (ten factorial)   at compile time. Print the result when the program is run. Discuss what limitations apply to compile-time calculations in your language.
#360_Assembly
360 Assembly
COMPCALA CSECT L R1,=A(FACT10) r1=10! XDECO R1,PG XPRNT PG,L'PG print buffer BR R14 exit FACT10 EQU 10*9*8*7*6*5*4*3*2*1 factorial computation PG DS CL12
http://rosettacode.org/wiki/Conjugate_transpose
Conjugate transpose
Suppose that a matrix M {\displaystyle M} contains complex numbers. Then the conjugate transpose of M {\displaystyle M} is a matrix M H {\displaystyle M^{H}} containing the complex conjugates of the matrix transposition of M {\displaystyle M} . ( M H ) j i = M i j ¯ {\displaystyle (M^{H})_{ji}={\overline {M_{ij}}}} This means that row j {\displaystyle j} , column i {\displaystyle i} of the conjugate transpose equals the complex conjugate of row i {\displaystyle i} , column j {\displaystyle j} of the original matrix. In the next list, M {\displaystyle M} must also be a square matrix. A Hermitian matrix equals its own conjugate transpose: M H = M {\displaystyle M^{H}=M} . A normal matrix is commutative in multiplication with its conjugate transpose: M H M = M M H {\displaystyle M^{H}M=MM^{H}} . A unitary matrix has its inverse equal to its conjugate transpose: M H = M − 1 {\displaystyle M^{H}=M^{-1}} . This is true iff M H M = I n {\displaystyle M^{H}M=I_{n}} and iff M M H = I n {\displaystyle MM^{H}=I_{n}} , where I n {\displaystyle I_{n}} is the identity matrix. Task Given some matrix of complex numbers, find its conjugate transpose. Also determine if the matrix is a: Hermitian matrix, normal matrix, or unitary matrix. See also MathWorld entry: conjugate transpose MathWorld entry: Hermitian matrix MathWorld entry: normal matrix MathWorld entry: unitary matrix
#Ruby
Ruby
require 'matrix'   # Start with some matrix. i = Complex::I matrix = Matrix[[i, 0, 0], [0, i, 0], [0, 0, i]]   # Find the conjugate transpose. # Matrix#conjugate appeared in Ruby 1.9.2. conjt = matrix.conj.t # aliases for matrix.conjugate.tranpose print 'conjugate tranpose: '; puts conjt   if matrix.square? # These predicates appeared in Ruby 1.9.3. print 'Hermitian? '; puts matrix.hermitian? print ' normal? '; puts matrix.normal? print ' unitary? '; puts matrix.unitary? else # Matrix is not square. These predicates would # raise ExceptionForMatrix::ErrDimensionMismatch. print 'Hermitian? false' print ' normal? false' print ' unitary? false' end
http://rosettacode.org/wiki/Compound_data_type
Compound data type
Data Structure This illustrates a data structure, a means of storing data within a program. You may see other such structures in the Data Structures category. Task Create a compound data type: Point(x,y) A compound data type is one that holds multiple independent values. Related task   Enumeration See also Array Associative array: Creation, Iteration Collections Compound data type Doubly-linked list: Definition, Element definition, Element insertion, List Traversal, Element Removal Linked list Queue: Definition, Usage Set Singly-linked list: Element definition, Element insertion, List Traversal, Element Removal Stack
#Elm
Elm
  --Compound Data type can hold multiple independent values --In Elm data can be compounded using List, Tuple, Record --In a List point = [2,5] --This creates a list having x and y which are independent and can be accessed by List functions --Note that x and y must be of same data type   --Tuple is another useful data type that stores different independent values point = (3,4) --Here we can have multiple data types point1 = ("x","y") point2 = (3,4.5) --The order of addressing matters --Using a Record is the best option point = {x=3,y=4} --To access point.x point.y --Or Use it as a function .x point .y point --Also to alter the value {point | x=7} {point | y=2} {point | x=3,y=4} --Each time a new record is generated --END  
http://rosettacode.org/wiki/Compound_data_type
Compound data type
Data Structure This illustrates a data structure, a means of storing data within a program. You may see other such structures in the Data Structures category. Task Create a compound data type: Point(x,y) A compound data type is one that holds multiple independent values. Related task   Enumeration See also Array Associative array: Creation, Iteration Collections Compound data type Doubly-linked list: Definition, Element definition, Element insertion, List Traversal, Element Removal Linked list Queue: Definition, Usage Set Singly-linked list: Element definition, Element insertion, List Traversal, Element Removal Stack
#Erlang
Erlang
  -module(records_test). -compile(export_all).   -record(point,{x,y}).   test() -> P1 = #point{x=1.0,y=2.0}, % creates a new point record io:fwrite("X: ~f, Y: ~f~n",[P1#point.x,P1#point.y]), P2 = P1#point{x=3.0}, % creates a new point record with x set to 3.0, y is copied from P1 io:fwrite("X: ~f, Y: ~f~n",[P2#point.x,P2#point.y]).  
http://rosettacode.org/wiki/Continued_fraction
Continued fraction
continued fraction Mathworld a 0 + b 1 a 1 + b 2 a 2 + b 3 a 3 + ⋱ {\displaystyle a_{0}+{\cfrac {b_{1}}{a_{1}+{\cfrac {b_{2}}{a_{2}+{\cfrac {b_{3}}{a_{3}+\ddots }}}}}}} The task is to write a program which generates such a number and prints a real representation of it. The code should be tested by calculating and printing the square root of 2, Napier's Constant, and Pi, using the following coefficients: For the square root of 2, use a 0 = 1 {\displaystyle a_{0}=1} then a N = 2 {\displaystyle a_{N}=2} . b N {\displaystyle b_{N}} is always 1 {\displaystyle 1} . 2 = 1 + 1 2 + 1 2 + 1 2 + ⋱ {\displaystyle {\sqrt {2}}=1+{\cfrac {1}{2+{\cfrac {1}{2+{\cfrac {1}{2+\ddots }}}}}}} For Napier's Constant, use a 0 = 2 {\displaystyle a_{0}=2} , then a N = N {\displaystyle a_{N}=N} . b 1 = 1 {\displaystyle b_{1}=1} then b N = N − 1 {\displaystyle b_{N}=N-1} . e = 2 + 1 1 + 1 2 + 2 3 + 3 4 + ⋱ {\displaystyle e=2+{\cfrac {1}{1+{\cfrac {1}{2+{\cfrac {2}{3+{\cfrac {3}{4+\ddots }}}}}}}}} For Pi, use a 0 = 3 {\displaystyle a_{0}=3} then a N = 6 {\displaystyle a_{N}=6} . b N = ( 2 N − 1 ) 2 {\displaystyle b_{N}=(2N-1)^{2}} . π = 3 + 1 6 + 9 6 + 25 6 + ⋱ {\displaystyle \pi =3+{\cfrac {1}{6+{\cfrac {9}{6+{\cfrac {25}{6+\ddots }}}}}}} See also   Continued fraction/Arithmetic for tasks that do arithmetic over continued fractions.
#Rust
Rust
  use std::iter;   // Calculating a continued fraction is quite easy with iterators, however // writing a proper iterator adapter is less so. We settle for a macro which // for most purposes works well enough. // // One limitation with this iterator based approach is that we cannot reverse // input iterators since they are not usually DoubleEnded. To circumvent this // we can collect the elements and then reverse them, however this isn't ideal // as we now have to store elements equal to the number of iterations. // // Another is that iterators cannot be resused once consumed, so it is often // required to make many clones of iterators. macro_rules! continued_fraction { ($a:expr, $b:expr ; $iterations:expr) => ( ($a).zip($b) .take($iterations) .collect::<Vec<_>>().iter() .rev() .fold(0 as f64, |acc: f64, &(x, y)| { x as f64 + (y as f64 / acc) }) );   ($a:expr, $b:expr) => (continued_fraction!($a, $b ; 1000)); }   fn main() { // Sqrt(2) let sqrt2a = (1..2).chain(iter::repeat(2)); let sqrt2b = iter::repeat(1); println!("{}", continued_fraction!(sqrt2a, sqrt2b));     // Napier's Constant let napiera = (2..3).chain(1..); let napierb = (1..2).chain(1..); println!("{}", continued_fraction!(napiera, napierb));     // Pi let pia = (3..4).chain(iter::repeat(6)); let pib = (1i64..).map(|x| (2 * x - 1).pow(2)); println!("{}", continued_fraction!(pia, pib)); }  
http://rosettacode.org/wiki/Copy_a_string
Copy a string
This task is about copying a string. Task Where it is relevant, distinguish between copying the contents of a string versus making an additional reference to an existing string. Other tasks related to string operations: Metrics Array length String length Copy a string Empty string  (assignment) Counting Word frequency Letter frequency Jewels and stones I before E except after C Bioinformatics/base count Count occurrences of a substring Count how many vowels and consonants occur in a string Remove/replace XXXX redacted Conjugate a Latin verb Remove vowels from a string String interpolation (included) Strip block comments Strip comments from a string Strip a set of characters from a string Strip whitespace from a string -- top and tail Strip control codes and extended characters from a string Anagrams/Derangements/shuffling Word wheel ABC problem Sattolo cycle Knuth shuffle Ordered words Superpermutation minimisation Textonyms (using a phone text pad) Anagrams Anagrams/Deranged anagrams Permutations/Derangements Find/Search/Determine ABC words Odd words Word ladder Semordnilap Word search Wordiff  (game) String matching Tea cup rim text Alternade words Changeable words State name puzzle String comparison Unique characters Unique characters in each string Extract file extension Levenshtein distance Palindrome detection Common list elements Longest common suffix Longest common prefix Compare a list of strings Longest common substring Find common directory path Words from neighbour ones Change e letters to i in words Non-continuous subsequences Longest common subsequence Longest palindromic substrings Longest increasing subsequence Words containing "the" substring Sum of the digits of n is substring of n Determine if a string is numeric Determine if a string is collapsible Determine if a string is squeezable Determine if a string has all unique characters Determine if a string has all the same characters Longest substrings without repeating characters Find words which contains all the vowels Find words which contains most consonants Find words which contains more than 3 vowels Find words which first and last three letters are equals Find words which odd letters are consonants and even letters are vowels or vice_versa Formatting Substring Rep-string Word wrap String case Align columns Literals/String Repeat a string Brace expansion Brace expansion using ranges Reverse a string Phrase reversals Comma quibbling Special characters String concatenation Substring/Top and tail Commatizing numbers Reverse words in a string Suffixation of decimal numbers Long literals, with continuations Numerical and alphabetical suffixes Abbreviations, easy Abbreviations, simple Abbreviations, automatic Song lyrics/poems/Mad Libs/phrases Mad Libs Magic 8-ball 99 Bottles of Beer The Name Game (a song) The Old lady swallowed a fly The Twelve Days of Christmas Tokenize Text between Tokenize a string Word break problem Tokenize a string with escaping Split a character string based on change of character Sequences Show ASCII table De Bruijn sequences Self-referential sequences Generate lower case ASCII alphabet
#PicoLisp
PicoLisp
(setq Str1 "abcdef") (setq Str2 Str1) # Create a reference to that symbol (setq Str3 (name Str1)) # Create new symbol with name "abcdef"
http://rosettacode.org/wiki/Copy_a_string
Copy a string
This task is about copying a string. Task Where it is relevant, distinguish between copying the contents of a string versus making an additional reference to an existing string. Other tasks related to string operations: Metrics Array length String length Copy a string Empty string  (assignment) Counting Word frequency Letter frequency Jewels and stones I before E except after C Bioinformatics/base count Count occurrences of a substring Count how many vowels and consonants occur in a string Remove/replace XXXX redacted Conjugate a Latin verb Remove vowels from a string String interpolation (included) Strip block comments Strip comments from a string Strip a set of characters from a string Strip whitespace from a string -- top and tail Strip control codes and extended characters from a string Anagrams/Derangements/shuffling Word wheel ABC problem Sattolo cycle Knuth shuffle Ordered words Superpermutation minimisation Textonyms (using a phone text pad) Anagrams Anagrams/Deranged anagrams Permutations/Derangements Find/Search/Determine ABC words Odd words Word ladder Semordnilap Word search Wordiff  (game) String matching Tea cup rim text Alternade words Changeable words State name puzzle String comparison Unique characters Unique characters in each string Extract file extension Levenshtein distance Palindrome detection Common list elements Longest common suffix Longest common prefix Compare a list of strings Longest common substring Find common directory path Words from neighbour ones Change e letters to i in words Non-continuous subsequences Longest common subsequence Longest palindromic substrings Longest increasing subsequence Words containing "the" substring Sum of the digits of n is substring of n Determine if a string is numeric Determine if a string is collapsible Determine if a string is squeezable Determine if a string has all unique characters Determine if a string has all the same characters Longest substrings without repeating characters Find words which contains all the vowels Find words which contains most consonants Find words which contains more than 3 vowels Find words which first and last three letters are equals Find words which odd letters are consonants and even letters are vowels or vice_versa Formatting Substring Rep-string Word wrap String case Align columns Literals/String Repeat a string Brace expansion Brace expansion using ranges Reverse a string Phrase reversals Comma quibbling Special characters String concatenation Substring/Top and tail Commatizing numbers Reverse words in a string Suffixation of decimal numbers Long literals, with continuations Numerical and alphabetical suffixes Abbreviations, easy Abbreviations, simple Abbreviations, automatic Song lyrics/poems/Mad Libs/phrases Mad Libs Magic 8-ball 99 Bottles of Beer The Name Game (a song) The Old lady swallowed a fly The Twelve Days of Christmas Tokenize Text between Tokenize a string Word break problem Tokenize a string with escaping Split a character string based on change of character Sequences Show ASCII table De Bruijn sequences Self-referential sequences Generate lower case ASCII alphabet
#Pike
Pike
int main(){ string hi = "Hello World."; string ih = hi; }
http://rosettacode.org/wiki/Constrained_random_points_on_a_circle
Constrained random points on a circle
Task Generate 100 <x,y> coordinate pairs such that x and y are integers sampled from the uniform distribution with the condition that 10 ≤ x 2 + y 2 ≤ 15 {\displaystyle 10\leq {\sqrt {x^{2}+y^{2}}}\leq 15} . Then display/plot them. The outcome should be a "fuzzy" circle. The actual number of points plotted may be less than 100, given that some pairs may be generated more than once. There are several possible approaches to accomplish this. Here are two possible algorithms. 1) Generate random pairs of integers and filter out those that don't satisfy this condition: 10 ≤ x 2 + y 2 ≤ 15 {\displaystyle 10\leq {\sqrt {x^{2}+y^{2}}}\leq 15} . 2) Precalculate the set of all possible points (there are 404 of them) and select randomly from this set.
#Lua
Lua
t, n = {}, 0 for y=1,31 do t[y]={} for x=1,31 do t[y][x]=" " end end repeat x, y = math.random(-15,15), math.random(-15,15) rsq = x*x + y*y if rsq>=100 and rsq<=225 and t[y+16][x+16]==" " then t[y+16][x+16], n = "██", n+1 end until n==100 for y=1,31 do print(table.concat(t[y])) end
http://rosettacode.org/wiki/Convex_hull
Convex hull
Find the points which form a convex hull from a set of arbitrary two dimensional points. For example, given the points (16,3), (12,17), (0,6), (-4,-6), (16,6), (16,-7), (16,-3), (17,-4), (5,19), (19,-8), (3,16), (12,13), (3,-4), (17,5), (-3,15), (-3,-9), (0,11), (-9,-3), (-4,-2) and (12,10) the convex hull would be (-9,-3), (-3,-9), (19,-8), (17,5), (12,17), (5,19) and (-3,15). See also Convex Hull (youtube) http://www.geeksforgeeks.org/convex-hull-set-2-graham-scan/
#Raku
Raku
class Point { has Real $.x is rw; has Real $.y is rw; method gist { [~] '(', self.x,', ', self.y, ')' }; }   sub ccw (Point $a, Point $b, Point $c) { ($b.x - $a.x)*($c.y - $a.y) - ($b.y - $a.y)*($c.x - $a.x); }   sub tangent (Point $a, Point $b) { my $opp = $b.x - $a.x; my $adj = $b.y - $a.y; $adj != 0 ?? $opp / $adj !! Inf }   sub graham-scan (**@coords) { # sort points by y, secondary sort on x my @sp = @coords.map( { Point.new( :x($_[0]), :y($_[1]) ) } ) .sort: {.y, .x};   # need at least 3 points to make a hull return @sp if +@sp < 3;   # first point on hull is minimum y point my @h = @sp.shift;   # re-sort the points by angle, secondary on x @sp = @sp.map( { $++ => [tangent(@h[0], $_), $_.x] } ) .sort( {-$_.value[0], $_.value[1] } ) .map: { @sp[$_.key] };   # first point of re-sorted list is guaranteed to be on hull @h.push: @sp.shift;   # check through the remaining list making sure that # there is always a positive angle for @sp -> $point { if ccw( |@h.tail(2), $point ) > 0 { @h.push: $point; } else { @h.pop; @h.push: $point and next if +@h < 2; redo; } } @h }   my @hull = graham-scan( (16, 3), (12,17), ( 0, 6), (-4,-6), (16, 6), (16,-7), (16,-3), (17,-4), ( 5,19), (19,-8), ( 3,16), (12,13), ( 3,-4), (17, 5), (-3,15), (-3,-9), ( 0,11), (-9,-3), (-4,-2), (12,10) );   say "Convex Hull ({+@hull} points): ", @hull;   @hull = graham-scan( (16, 3), (12,17), ( 0, 6), (-4,-6), (16, 6), (16,-7), (16,-3), (17,-4), ( 5,19), (19,-8), ( 3,16), (12,13), ( 3,-4), (17, 5), (-3,15), (-3,-9), ( 0,11), (-9,-3), (-4,-2), (12,10), (20,-9), (1,-9) );   say "Convex Hull ({+@hull} points): ", @hull;
http://rosettacode.org/wiki/Convert_seconds_to_compound_duration
Convert seconds to compound duration
Task Write a function or program which:   takes a positive integer representing a duration in seconds as input (e.g., 100), and   returns a string which shows the same duration decomposed into:   weeks,   days,   hours,   minutes,   and   seconds. This is detailed below (e.g., "2 hr, 59 sec"). Demonstrate that it passes the following three test-cases: Test Cases input number output string 7259 2 hr, 59 sec 86400 1 d 6000000 9 wk, 6 d, 10 hr, 40 min Details The following five units should be used: unit suffix used in output conversion week wk 1 week = 7 days day d 1 day = 24 hours hour hr 1 hour = 60 minutes minute min 1 minute = 60 seconds second sec However, only include quantities with non-zero values in the output (e.g., return "1 d" and not "0 wk, 1 d, 0 hr, 0 min, 0 sec"). Give larger units precedence over smaller ones as much as possible (e.g., return 2 min, 10 sec and not 1 min, 70 sec or 130 sec) Mimic the formatting shown in the test-cases (quantities sorted from largest unit to smallest and separated by comma+space; value and unit of each quantity separated by space).
#Run_BASIC
Run BASIC
sec = 6000005 week = int(sec/60/60/24/7) day = int(sec/60/60/24) mod 7 hour = int(sec/60/60) mod 24 minute = int(sec/60) mod 60 second = sec mod 60   print sec;" seconds is "; if week > 0 then print week;" weeks "; if day > 0 then print day;" days "; if hour > 0 then print hour;" hours "; if minute > 0 then print minute;" minutes "; if second > 0 then print second;" seconds"
http://rosettacode.org/wiki/Convert_seconds_to_compound_duration
Convert seconds to compound duration
Task Write a function or program which:   takes a positive integer representing a duration in seconds as input (e.g., 100), and   returns a string which shows the same duration decomposed into:   weeks,   days,   hours,   minutes,   and   seconds. This is detailed below (e.g., "2 hr, 59 sec"). Demonstrate that it passes the following three test-cases: Test Cases input number output string 7259 2 hr, 59 sec 86400 1 d 6000000 9 wk, 6 d, 10 hr, 40 min Details The following five units should be used: unit suffix used in output conversion week wk 1 week = 7 days day d 1 day = 24 hours hour hr 1 hour = 60 minutes minute min 1 minute = 60 seconds second sec However, only include quantities with non-zero values in the output (e.g., return "1 d" and not "0 wk, 1 d, 0 hr, 0 min, 0 sec"). Give larger units precedence over smaller ones as much as possible (e.g., return 2 min, 10 sec and not 1 min, 70 sec or 130 sec) Mimic the formatting shown in the test-cases (quantities sorted from largest unit to smallest and separated by comma+space; value and unit of each quantity separated by space).
#Rust
Rust
use std::fmt;     struct CompoundTime { w: usize, d: usize, h: usize, m: usize, s: usize, }   macro_rules! reduce { ($s: ident, $(($from: ident, $to: ident, $factor: expr)),+) => {{ $( $s.$to += $s.$from / $factor; $s.$from %= $factor; )+ }} }   impl CompoundTime { #[inline] fn new(w: usize, d: usize, h: usize, m: usize, s: usize) -> Self{ CompoundTime { w: w, d: d, h: h, m: m, s: s, } }   #[inline] fn balance(&mut self) { reduce!(self, (s, m, 60), (m, h, 60), (h, d, 24), (d, w, 7)); } }   impl fmt::Display for CompoundTime { fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result { write!(f, "{}w {}d {}h {}m {}s", self.w, self.d, self.h, self.m, self.s) } }   fn main() { let mut ct = CompoundTime::new(0,3,182,345,2412); println!("Before: {}", ct); ct.balance(); println!("After: {}", ct); }
http://rosettacode.org/wiki/Concurrent_computing
Concurrent computing
Task Using either native language concurrency syntax or freely available libraries, write a program to display the strings "Enjoy" "Rosetta" "Code", one string per line, in random order. Concurrency syntax must use threads, tasks, co-routines, or whatever concurrency is called in your language.
#Java
Java
import java.util.concurrent.CyclicBarrier;   public class Threads { public static class DelayedMessagePrinter implements Runnable { private CyclicBarrier barrier; private String msg;   public DelayedMessagePrinter(CyclicBarrier barrier, String msg) { this.barrier = barrier; this.msg = msg; }   public void run() { try { barrier.await(); } catch (Exception e) { } System.out.println(msg); } }   public static void main(String[] args) { CyclicBarrier barrier = new CyclicBarrier(3); new Thread(new DelayedMessagePrinter(barrier, "Enjoy")).start(); new Thread(new DelayedMessagePrinter(barrier, "Rosetta")).start(); new Thread(new DelayedMessagePrinter(barrier, "Code")).start(); } }
http://rosettacode.org/wiki/Concurrent_computing
Concurrent computing
Task Using either native language concurrency syntax or freely available libraries, write a program to display the strings "Enjoy" "Rosetta" "Code", one string per line, in random order. Concurrency syntax must use threads, tasks, co-routines, or whatever concurrency is called in your language.
#JavaScript
JavaScript
self.addEventListener('message', function (event) { self.postMessage(event.data); self.close(); }, false);
http://rosettacode.org/wiki/Compile-time_calculation
Compile-time calculation
Some programming languages allow calculation of values at compile time. Task Calculate   10!   (ten factorial)   at compile time. Print the result when the program is run. Discuss what limitations apply to compile-time calculations in your language.
#6502_Assembly
6502 Assembly
; Display the value of 10!, which is precomputed at assembly time ; on any Commodore 8-bit.   .ifndef __CBM__ .error "Target must be a Commodore system." .endif   ; zero-page work pointer temp = $fb   ; ROM routines used chrout = $ffd2   .code   lda #<tenfactorial sta temp lda #>tenfactorial sta temp+1 ldy #0 loop: lda (temp),y beq done jsr chrout iny bne loop done: rts   .data   ; the actual value to print tenfactorial: .byte 13,"10! = ",.string(10*9*8*7*6*5*4*3*2*1),13,0
http://rosettacode.org/wiki/Compile-time_calculation
Compile-time calculation
Some programming languages allow calculation of values at compile time. Task Calculate   10!   (ten factorial)   at compile time. Print the result when the program is run. Discuss what limitations apply to compile-time calculations in your language.
#68000_Assembly
68000 Assembly
tenfactorial equ 10*9*8*7*6*5*4*3*2   MOVE.L #tenfactorial,D1 ;load the constant integer 10! into D1 LEA tenfactorial,A1 ;load into A1 the memory address 10! = 0x375F00 ADD.L #tenfactorial,D2 ;add 10! to whatever is stored in D2 and store the result in D2
http://rosettacode.org/wiki/Conjugate_transpose
Conjugate transpose
Suppose that a matrix M {\displaystyle M} contains complex numbers. Then the conjugate transpose of M {\displaystyle M} is a matrix M H {\displaystyle M^{H}} containing the complex conjugates of the matrix transposition of M {\displaystyle M} . ( M H ) j i = M i j ¯ {\displaystyle (M^{H})_{ji}={\overline {M_{ij}}}} This means that row j {\displaystyle j} , column i {\displaystyle i} of the conjugate transpose equals the complex conjugate of row i {\displaystyle i} , column j {\displaystyle j} of the original matrix. In the next list, M {\displaystyle M} must also be a square matrix. A Hermitian matrix equals its own conjugate transpose: M H = M {\displaystyle M^{H}=M} . A normal matrix is commutative in multiplication with its conjugate transpose: M H M = M M H {\displaystyle M^{H}M=MM^{H}} . A unitary matrix has its inverse equal to its conjugate transpose: M H = M − 1 {\displaystyle M^{H}=M^{-1}} . This is true iff M H M = I n {\displaystyle M^{H}M=I_{n}} and iff M M H = I n {\displaystyle MM^{H}=I_{n}} , where I n {\displaystyle I_{n}} is the identity matrix. Task Given some matrix of complex numbers, find its conjugate transpose. Also determine if the matrix is a: Hermitian matrix, normal matrix, or unitary matrix. See also MathWorld entry: conjugate transpose MathWorld entry: Hermitian matrix MathWorld entry: normal matrix MathWorld entry: unitary matrix
#Rust
Rust
  extern crate num; // crate for complex numbers   use num::complex::Complex; use std::ops::Mul; use std::fmt;     #[derive(Debug, PartialEq)] struct Matrix<f32> { grid: [[Complex<f32>; 2]; 2], // used to represent matrix }     impl Matrix<f32> { // implements a method call for calculating the conjugate transpose fn conjugate_transpose(&self) -> Matrix<f32> { Matrix {grid: [[self.grid[0][0].conj(), self.grid[1][0].conj()], [self.grid[0][1].conj(), self.grid[1][1].conj()]]} } }   impl Mul for Matrix<f32> { // implements '*' (multiplication) for the matrix type Output = Matrix<f32>;   fn mul(self, other: Matrix<f32>) -> Matrix<f32> { Matrix {grid: [[self.grid[0][0]*other.grid[0][0] + self.grid[0][1]*other.grid[1][0], self.grid[0][0]*other.grid[0][1] + self.grid[0][1]*other.grid[1][1]], [self.grid[1][0]*other.grid[0][0] + self.grid[1][1]*other.grid[1][0], self.grid[1][0]*other.grid[1][0] + self.grid[1][1]*other.grid[1][1]]]} } }   impl Copy for Matrix<f32> {} // implemented to prevent 'moved value' errors in if statements below impl Clone for Matrix<f32> { fn clone(&self) -> Matrix<f32> { *self } }   impl fmt::Display for Matrix<f32> { // implemented to make output nicer fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result { write!(f, "({}, {})\n({}, {})", self.grid[0][0], self.grid[0][1], self.grid[1][0], self.grid[1][1]) } }   fn main() { let a = Matrix {grid: [[Complex::new(3.0, 0.0), Complex::new(2.0, 1.0)], [Complex::new(2.0, -1.0), Complex::new(1.0, 0.0)]]};   let b = Matrix {grid: [[Complex::new(0.5, 0.5), Complex::new(0.5, -0.5)], [Complex::new(0.5, -0.5), Complex::new(0.5, 0.5)]]};   test_type(a); test_type(b); }   fn test_type(mat: Matrix<f32>) { let identity = Matrix {grid: [[Complex::new(1.0, 0.0), Complex::new(0.0, 0.0)], [Complex::new(0.0, 0.0), Complex::new(1.0, 0.0)]]}; let mat_conj = mat.conjugate_transpose();   println!("Matrix: \n{}\nConjugate transpose: \n{}", mat, mat_conj);   if mat == mat_conj { println!("Hermitian?: TRUE"); } else { println!("Hermitian?: FALSE"); }   if mat*mat_conj == mat_conj*mat { println!("Normal?: TRUE"); } else { println!("Normal?: FALSE"); }   if mat*mat_conj == identity { println!("Unitary?: TRUE"); } else { println!("Unitary?: FALSE"); } }
http://rosettacode.org/wiki/Conjugate_transpose
Conjugate transpose
Suppose that a matrix M {\displaystyle M} contains complex numbers. Then the conjugate transpose of M {\displaystyle M} is a matrix M H {\displaystyle M^{H}} containing the complex conjugates of the matrix transposition of M {\displaystyle M} . ( M H ) j i = M i j ¯ {\displaystyle (M^{H})_{ji}={\overline {M_{ij}}}} This means that row j {\displaystyle j} , column i {\displaystyle i} of the conjugate transpose equals the complex conjugate of row i {\displaystyle i} , column j {\displaystyle j} of the original matrix. In the next list, M {\displaystyle M} must also be a square matrix. A Hermitian matrix equals its own conjugate transpose: M H = M {\displaystyle M^{H}=M} . A normal matrix is commutative in multiplication with its conjugate transpose: M H M = M M H {\displaystyle M^{H}M=MM^{H}} . A unitary matrix has its inverse equal to its conjugate transpose: M H = M − 1 {\displaystyle M^{H}=M^{-1}} . This is true iff M H M = I n {\displaystyle M^{H}M=I_{n}} and iff M M H = I n {\displaystyle MM^{H}=I_{n}} , where I n {\displaystyle I_{n}} is the identity matrix. Task Given some matrix of complex numbers, find its conjugate transpose. Also determine if the matrix is a: Hermitian matrix, normal matrix, or unitary matrix. See also MathWorld entry: conjugate transpose MathWorld entry: Hermitian matrix MathWorld entry: normal matrix MathWorld entry: unitary matrix
#Scala
Scala
object ConjugateTranspose {   case class Complex(re: Double, im: Double) { def conjugate(): Complex = Complex(re, -im) def +(other: Complex) = Complex(re + other.re, im + other.im) def *(other: Complex) = Complex(re * other.re - im * other.im, re * other.im + im * other.re) override def toString(): String = { if (im < 0) { s"${re}${im}i" } else { s"${re}+${im}i" } } }   case class Matrix(val entries: Vector[Vector[Complex]]) {   def *(other: Matrix): Matrix = { new Matrix( Vector.tabulate(entries.size, other.entries(0).size)((r, c) => { val rightRow = entries(r) val leftCol = other.entries.map(_(c)) rightRow.zip(leftCol) .map{ case (x, y) => x * y } // multiply pair-wise .foldLeft(new Complex(0,0)){ case (x, y) => x + y } // sum over all }) ) }   def conjugateTranspose(): Matrix = { new Matrix( Vector.tabulate(entries(0).size, entries.size)((r, c) => entries(c)(r).conjugate) ) }   def isHermitian(): Boolean = { this == conjugateTranspose() }   def isNormal(): Boolean = { val ct = conjugateTranspose() this * ct == ct * this }   def isIdentity(): Boolean = { val entriesWithIndexes = for (r <- 0 until entries.size; c <- 0 until entries(r).size) yield (r, c, entries(r)(c)) entriesWithIndexes.forall { case (r, c, x) => if (r == c) { x == Complex(1.0, 0.0) } else { x == Complex(0.0, 0.0) } } }   def isUnitary(): Boolean = { (this * conjugateTranspose()).isIdentity() }   override def toString(): String = { entries.map(" " + _.mkString("[", ",", "]")).mkString("[\n", "\n", "\n]") }   }   def main(args: Array[String]): Unit = { val m = new Matrix( Vector.fill(3, 3)(new Complex(Math.random() * 2 - 1.0, Math.random() * 2 - 1.0)) ) println("Matrix: " + m) println("Conjugate Transpose: " + m.conjugateTranspose()) println("Hermitian: " + m.isHermitian()) println("Normal: " + m.isNormal()) println("Unitary: " + m.isUnitary()) }   }
http://rosettacode.org/wiki/Compound_data_type
Compound data type
Data Structure This illustrates a data structure, a means of storing data within a program. You may see other such structures in the Data Structures category. Task Create a compound data type: Point(x,y) A compound data type is one that holds multiple independent values. Related task   Enumeration See also Array Associative array: Creation, Iteration Collections Compound data type Doubly-linked list: Definition, Element definition, Element insertion, List Traversal, Element Removal Linked list Queue: Definition, Usage Set Singly-linked list: Element definition, Element insertion, List Traversal, Element Removal Stack
#Euphoria
Euphoria
  enum x, y   sequence point = {0,0}   printf(1,"x = %d, y = %3.3f\n",point)   point[x] = 'A' point[y] = 53.42   printf(1,"x = %d, y = %3.3f\n",point) printf(1,"x = %s, y = %3.3f\n",point)  
http://rosettacode.org/wiki/Continued_fraction
Continued fraction
continued fraction Mathworld a 0 + b 1 a 1 + b 2 a 2 + b 3 a 3 + ⋱ {\displaystyle a_{0}+{\cfrac {b_{1}}{a_{1}+{\cfrac {b_{2}}{a_{2}+{\cfrac {b_{3}}{a_{3}+\ddots }}}}}}} The task is to write a program which generates such a number and prints a real representation of it. The code should be tested by calculating and printing the square root of 2, Napier's Constant, and Pi, using the following coefficients: For the square root of 2, use a 0 = 1 {\displaystyle a_{0}=1} then a N = 2 {\displaystyle a_{N}=2} . b N {\displaystyle b_{N}} is always 1 {\displaystyle 1} . 2 = 1 + 1 2 + 1 2 + 1 2 + ⋱ {\displaystyle {\sqrt {2}}=1+{\cfrac {1}{2+{\cfrac {1}{2+{\cfrac {1}{2+\ddots }}}}}}} For Napier's Constant, use a 0 = 2 {\displaystyle a_{0}=2} , then a N = N {\displaystyle a_{N}=N} . b 1 = 1 {\displaystyle b_{1}=1} then b N = N − 1 {\displaystyle b_{N}=N-1} . e = 2 + 1 1 + 1 2 + 2 3 + 3 4 + ⋱ {\displaystyle e=2+{\cfrac {1}{1+{\cfrac {1}{2+{\cfrac {2}{3+{\cfrac {3}{4+\ddots }}}}}}}}} For Pi, use a 0 = 3 {\displaystyle a_{0}=3} then a N = 6 {\displaystyle a_{N}=6} . b N = ( 2 N − 1 ) 2 {\displaystyle b_{N}=(2N-1)^{2}} . π = 3 + 1 6 + 9 6 + 25 6 + ⋱ {\displaystyle \pi =3+{\cfrac {1}{6+{\cfrac {9}{6+{\cfrac {25}{6+\ddots }}}}}}} See also   Continued fraction/Arithmetic for tasks that do arithmetic over continued fractions.
#Scala
Scala
object CF extends App { import Stream._ val sqrt2 = 1 #:: from(2,0) zip from(1,0) val napier = 2 #:: from(1) zip (1 #:: from(1)) val pi = 3 #:: from(6,0) zip (from(1,2) map {x=>x*x})   // reference values, source: wikipedia val refPi = "3.14159265358979323846264338327950288419716939937510" val refNapier = "2.71828182845904523536028747135266249775724709369995" val refSQRT2 = "1.41421356237309504880168872420969807856967187537694"   def calc(cf: Stream[(Int, Int)], numberOfIters: Int=200): BigDecimal = { (cf take numberOfIters toList).foldRight[BigDecimal](1)((a, z) => a._1+a._2/z) }   def approx(cfV: BigDecimal, cfRefV: String): String = { val p: Pair[Char,Char] => Boolean = pair =>(pair._1==pair._2) ((cfV.toString+" "*34).substring(0,34) zip cfRefV.toString.substring(0,34)) .takeWhile(p).foldRight[String]("")((a:Pair[Char,Char],z)=>a._1+z) }   List(("sqrt2",sqrt2,50,refSQRT2),("napier",napier,50,refNapier),("pi",pi,3000,refPi)) foreach {t=> val (name,cf,iters,refV) = t val cfV = calc(cf,iters) println(name+":") println("ref value: "+refV.substring(0,34)) println("cf value: "+(cfV.toString+" "*34).substring(0,34)) println("precision: "+approx(cfV,refV)) println() } }
http://rosettacode.org/wiki/Copy_a_string
Copy a string
This task is about copying a string. Task Where it is relevant, distinguish between copying the contents of a string versus making an additional reference to an existing string. Other tasks related to string operations: Metrics Array length String length Copy a string Empty string  (assignment) Counting Word frequency Letter frequency Jewels and stones I before E except after C Bioinformatics/base count Count occurrences of a substring Count how many vowels and consonants occur in a string Remove/replace XXXX redacted Conjugate a Latin verb Remove vowels from a string String interpolation (included) Strip block comments Strip comments from a string Strip a set of characters from a string Strip whitespace from a string -- top and tail Strip control codes and extended characters from a string Anagrams/Derangements/shuffling Word wheel ABC problem Sattolo cycle Knuth shuffle Ordered words Superpermutation minimisation Textonyms (using a phone text pad) Anagrams Anagrams/Deranged anagrams Permutations/Derangements Find/Search/Determine ABC words Odd words Word ladder Semordnilap Word search Wordiff  (game) String matching Tea cup rim text Alternade words Changeable words State name puzzle String comparison Unique characters Unique characters in each string Extract file extension Levenshtein distance Palindrome detection Common list elements Longest common suffix Longest common prefix Compare a list of strings Longest common substring Find common directory path Words from neighbour ones Change e letters to i in words Non-continuous subsequences Longest common subsequence Longest palindromic substrings Longest increasing subsequence Words containing "the" substring Sum of the digits of n is substring of n Determine if a string is numeric Determine if a string is collapsible Determine if a string is squeezable Determine if a string has all unique characters Determine if a string has all the same characters Longest substrings without repeating characters Find words which contains all the vowels Find words which contains most consonants Find words which contains more than 3 vowels Find words which first and last three letters are equals Find words which odd letters are consonants and even letters are vowels or vice_versa Formatting Substring Rep-string Word wrap String case Align columns Literals/String Repeat a string Brace expansion Brace expansion using ranges Reverse a string Phrase reversals Comma quibbling Special characters String concatenation Substring/Top and tail Commatizing numbers Reverse words in a string Suffixation of decimal numbers Long literals, with continuations Numerical and alphabetical suffixes Abbreviations, easy Abbreviations, simple Abbreviations, automatic Song lyrics/poems/Mad Libs/phrases Mad Libs Magic 8-ball 99 Bottles of Beer The Name Game (a song) The Old lady swallowed a fly The Twelve Days of Christmas Tokenize Text between Tokenize a string Word break problem Tokenize a string with escaping Split a character string based on change of character Sequences Show ASCII table De Bruijn sequences Self-referential sequences Generate lower case ASCII alphabet
#PL.2FI
PL/I
declare (s1, s2) character (20) varying; s1 = 'now is the time'; s2 = s1;
http://rosettacode.org/wiki/Copy_a_string
Copy a string
This task is about copying a string. Task Where it is relevant, distinguish between copying the contents of a string versus making an additional reference to an existing string. Other tasks related to string operations: Metrics Array length String length Copy a string Empty string  (assignment) Counting Word frequency Letter frequency Jewels and stones I before E except after C Bioinformatics/base count Count occurrences of a substring Count how many vowels and consonants occur in a string Remove/replace XXXX redacted Conjugate a Latin verb Remove vowels from a string String interpolation (included) Strip block comments Strip comments from a string Strip a set of characters from a string Strip whitespace from a string -- top and tail Strip control codes and extended characters from a string Anagrams/Derangements/shuffling Word wheel ABC problem Sattolo cycle Knuth shuffle Ordered words Superpermutation minimisation Textonyms (using a phone text pad) Anagrams Anagrams/Deranged anagrams Permutations/Derangements Find/Search/Determine ABC words Odd words Word ladder Semordnilap Word search Wordiff  (game) String matching Tea cup rim text Alternade words Changeable words State name puzzle String comparison Unique characters Unique characters in each string Extract file extension Levenshtein distance Palindrome detection Common list elements Longest common suffix Longest common prefix Compare a list of strings Longest common substring Find common directory path Words from neighbour ones Change e letters to i in words Non-continuous subsequences Longest common subsequence Longest palindromic substrings Longest increasing subsequence Words containing "the" substring Sum of the digits of n is substring of n Determine if a string is numeric Determine if a string is collapsible Determine if a string is squeezable Determine if a string has all unique characters Determine if a string has all the same characters Longest substrings without repeating characters Find words which contains all the vowels Find words which contains most consonants Find words which contains more than 3 vowels Find words which first and last three letters are equals Find words which odd letters are consonants and even letters are vowels or vice_versa Formatting Substring Rep-string Word wrap String case Align columns Literals/String Repeat a string Brace expansion Brace expansion using ranges Reverse a string Phrase reversals Comma quibbling Special characters String concatenation Substring/Top and tail Commatizing numbers Reverse words in a string Suffixation of decimal numbers Long literals, with continuations Numerical and alphabetical suffixes Abbreviations, easy Abbreviations, simple Abbreviations, automatic Song lyrics/poems/Mad Libs/phrases Mad Libs Magic 8-ball 99 Bottles of Beer The Name Game (a song) The Old lady swallowed a fly The Twelve Days of Christmas Tokenize Text between Tokenize a string Word break problem Tokenize a string with escaping Split a character string based on change of character Sequences Show ASCII table De Bruijn sequences Self-referential sequences Generate lower case ASCII alphabet
#Pop11
Pop11
vars src, dst; 'Hello' -> src; copy(src) -> dst;
http://rosettacode.org/wiki/Constrained_random_points_on_a_circle
Constrained random points on a circle
Task Generate 100 <x,y> coordinate pairs such that x and y are integers sampled from the uniform distribution with the condition that 10 ≤ x 2 + y 2 ≤ 15 {\displaystyle 10\leq {\sqrt {x^{2}+y^{2}}}\leq 15} . Then display/plot them. The outcome should be a "fuzzy" circle. The actual number of points plotted may be less than 100, given that some pairs may be generated more than once. There are several possible approaches to accomplish this. Here are two possible algorithms. 1) Generate random pairs of integers and filter out those that don't satisfy this condition: 10 ≤ x 2 + y 2 ≤ 15 {\displaystyle 10\leq {\sqrt {x^{2}+y^{2}}}\leq 15} . 2) Precalculate the set of all possible points (there are 404 of them) and select randomly from this set.
#Maple
Maple
a := table(): i := 1: while i < 100 do ba := (rand(-15 .. 15))(): bb := (rand(-15 .. 15))(): b := evalf(sqrt(ba^2+bb^2)): if b <= 15 and b >= 10 then a[i] := [ba, bb]: i := i+1: end if: end do: plots:-pointplot(convert(a,list));
http://rosettacode.org/wiki/Convex_hull
Convex hull
Find the points which form a convex hull from a set of arbitrary two dimensional points. For example, given the points (16,3), (12,17), (0,6), (-4,-6), (16,6), (16,-7), (16,-3), (17,-4), (5,19), (19,-8), (3,16), (12,13), (3,-4), (17,5), (-3,15), (-3,-9), (0,11), (-9,-3), (-4,-2) and (12,10) the convex hull would be (-9,-3), (-3,-9), (19,-8), (17,5), (12,17), (5,19) and (-3,15). See also Convex Hull (youtube) http://www.geeksforgeeks.org/convex-hull-set-2-graham-scan/
#RATFOR
RATFOR
# # Convex hulls by Andrew's monotone chain algorithm. # # For a description of the algorithm, see # https://en.wikibooks.org/w/index.php?title=Algorithm_Implementation/Geometry/Convex_hull/Monotone_chain&stableid=40169 # # As in the Fortran 2018 version upon which this code is based, I # shall use the built-in "complex" type to represent "points" in the # plane. This is merely for convenience, rather than to express a # mathematical equivalence. #   define(point, complex)   function x (u)   # Return the x-coordinate of "point" u.   implicit none   point u real x   x = real (u) end   function y (u)   # Return the y-coordinate of "point" u.   implicit none   point u real y   y = aimag (u) end   function cross (u, v)   # Return, as a signed scalar, the cross product of "points" u and v # (regarded as "vectors" or multivectors).   implicit none   point u, v real cross, x, y   cross = (x (u) * y (v)) - (y (u) * x (v)) end   subroutine sortpt (numpt, pt)   # Sort "points" in ascending order, first by the x-coordinates and # then by the y-coordinates. Any decent sort algorithm will suffice; # for the sake of interest, here is the Shell sort of # https://en.wikipedia.org/w/index.php?title=Shellsort&oldid=1084744510   implicit none   integer numpt point pt(0:*)   real x, y integer i, j, k, gap, offset point temp logical done   integer gaps(1:8) data gaps / 701, 301, 132, 57, 23, 10, 4, 1 /   for (k = 1; k <= 8; k = k + 1) { gap = gaps(k) for (offset = 0; offset <= gap - 1; offset = offset + 1) for (i = offset; i <= numpt - 1; i = i + gap) { temp = pt(i) j = i done = .false. while (!done) { if (j < gap) done = .true. else if (x (pt(j - gap)) < x (temp)) done = .true. else if (x (pt(j - gap)) == x (temp) _ && (y (pt(j - gap)) <= y (temp))) done = .true. else { pt(j) = pt(j - gap) j = j - gap } } pt(j) = temp } } end   subroutine deltrd (n, pt)   # Delete trailing neighbor duplicates.   implicit none   integer n point pt(0:*)   integer i logical done   i = n - 1 done = .false. while (!done) { if (i == 0) { n = 1 done = .true. } else if (pt(i - 1) != pt(i)) { n = i + 1 done = .true. } else i = i - 1 } end   subroutine delntd (n, pt)   # Delete non-trailing neighbor duplicates.   implicit none   integer n point pt(0:*)   integer i, j, numdel logical done   i = 0 while (i < n - 1) { j = i + 1 done = .false. while (!done) { if (j == n) done = .true. else if (pt(j) != pt(i)) done = .true. else j = j + 1 } if (j != i + 1) { numdel = j - i - 1 while (j != n) { pt(j - numdel) = pt(j) j = j + 1 } n = n - numdel } i = i + 1 } end   subroutine deldup (n, pt)   # Delete neighbor duplicates.   implicit none   integer n point pt(0:*)   call deltrd (n, pt) call delntd (n, pt) end   subroutine cxlhul (n, pt, hullsz, hull)   # Construct the lower hull.   implicit none   integer n # Number of points. point pt(0:*) integer hullsz # Output. point hull(0:*) # Output.   real cross integer i, j logical done   j = 1 hull(0) = pt(0) hull(1) = pt(1) for (i = 2; i <= n - 1; i = i + 1) { done = .false. while (!done) { if (j == 0) { j = j + 1 hull(j) = pt(i) done = .true. } else if (0.0 < cross (hull(j) - hull(j - 1), _ pt(i) - hull(j - 1))) { j = j + 1 hull(j) = pt(i) done = .true. } else j = j - 1 } } hullsz = j + 1 end   subroutine cxuhul (n, pt, hullsz, hull)   # Construct the upper hull.   implicit none   integer n # Number of points. point pt(0:*) integer hullsz # Output. point hull(0:*) # Output.   real cross integer i, j logical done   j = 1 hull(0) = pt(n - 1) hull(1) = pt(n - 2) for (i = n - 3; 0 <= i; i = i - 1) { done = .false. while (!done) { if (j == 0) { j = j + 1 hull(j) = pt(i) done = .true. } else if (0.0 < cross (hull(j) - hull(j - 1), _ pt(i) - hull(j - 1))) { j = j + 1 hull(j) = pt(i) done = .true. } else j = j - 1 } } hullsz = j + 1 end   subroutine cxhull (n, pt, hullsz, lhull, uhull)   # Construct the hull.   implicit none   integer n # Number of points. point pt(0:*) # Overwritten with hull. integer hullsz # Output. point lhull(0:*) # Workspace. point uhull(0:*) # Workspace   integer lhulsz, uhulsz, i   # A side note: the calls to construct_lower_hull and # construct_upper_hull could be done in parallel. call cxlhul (n, pt, lhulsz, lhull) call cxuhul (n, pt, uhulsz, uhull)   hullsz = lhulsz + uhulsz - 2   for (i = 0; i <= lhulsz - 2; i = i + 1) pt(i) = lhull(i) for (i = 0; i <= uhulsz - 2; i = i + 1) pt(lhulsz - 1 + i) = uhull(i) end   subroutine cvxhul (n, pt, hullsz, lhull, uhull)   # Find a convex hull.   implicit none   integer n # Number of points. point pt(0:*) # The contents of pt is replaced with the hull. integer hullsz # Output. point lhull(0:*) # Workspace. point uhull(0:*) # Workspace   integer numpt   numpt = n   call sortpt (numpt, pt) call deldup (numpt, pt)   if (numpt == 0) hullsz = 0 else if (numpt <= 2) hullsz = numpt else call cxhull (numpt, pt, hullsz, lhull, uhull) end   program cvxtsk   # The Rosetta Code convex hull task.   implicit none   integer n, i point points(0:100) point lhull(0:100) point uhull(0:100) character*100 fmt   point exampl(0:19) data exampl / (16, 3), (12, 17), (0, 6), (-4, -6), (16, 6), _ (16, -7), (16, -3), (17, -4), (5, 19), (19, -8), _ (3, 16), (12, 13), (3, -4), (17, 5), (-3, 15), _ (-3, -9), (0, 11), (-9, -3), (-4, -2), (12, 10) /   n = 20 for (i = 0; i <= n - 1; i = i + 1) points(i) = exampl(i) call cvxhul (n, points, n, lhull, uhull)   write (fmt, '("(", I20, ''("(", F3.0, 1X, F3.0, ") ")'', ")")') n write (*, fmt) (points(i), i = 0, n - 1) end
http://rosettacode.org/wiki/Convert_seconds_to_compound_duration
Convert seconds to compound duration
Task Write a function or program which:   takes a positive integer representing a duration in seconds as input (e.g., 100), and   returns a string which shows the same duration decomposed into:   weeks,   days,   hours,   minutes,   and   seconds. This is detailed below (e.g., "2 hr, 59 sec"). Demonstrate that it passes the following three test-cases: Test Cases input number output string 7259 2 hr, 59 sec 86400 1 d 6000000 9 wk, 6 d, 10 hr, 40 min Details The following five units should be used: unit suffix used in output conversion week wk 1 week = 7 days day d 1 day = 24 hours hour hr 1 hour = 60 minutes minute min 1 minute = 60 seconds second sec However, only include quantities with non-zero values in the output (e.g., return "1 d" and not "0 wk, 1 d, 0 hr, 0 min, 0 sec"). Give larger units precedence over smaller ones as much as possible (e.g., return 2 min, 10 sec and not 1 min, 70 sec or 130 sec) Mimic the formatting shown in the test-cases (quantities sorted from largest unit to smallest and separated by comma+space; value and unit of each quantity separated by space).
#Scala
Scala
//Converting Seconds to Compound Duration   object seconds{ def main( args:Array[String] ){   println("Enter the no.") val input = scala.io.StdIn.readInt()   var week_r:Int = input % 604800 var week:Int = (input - week_r)/604800   var day_r:Int = week_r % 86400 var day:Int = (week_r - day_r)/86400   var hour_r:Int = day_r % 3600 var hour:Int = (day_r - hour_r)/3600   var minute_r:Int = hour_r % 60 var minute:Int = (hour_r - minute_r)/60   var sec:Int = minute_r % 60   println("Week = " + week) println("Day = " + day) println("Hour = " + hour) println("Minute = " + minute) println("Second = " + sec) } }
http://rosettacode.org/wiki/Concurrent_computing
Concurrent computing
Task Using either native language concurrency syntax or freely available libraries, write a program to display the strings "Enjoy" "Rosetta" "Code", one string per line, in random order. Concurrency syntax must use threads, tasks, co-routines, or whatever concurrency is called in your language.
#Julia
Julia
words = ["Enjoy", "Rosetta", "Code"]   function sleepprint(s) sleep(rand()) println(s) end   @sync for word in words @async sleepprint(word) end
http://rosettacode.org/wiki/Concurrent_computing
Concurrent computing
Task Using either native language concurrency syntax or freely available libraries, write a program to display the strings "Enjoy" "Rosetta" "Code", one string per line, in random order. Concurrency syntax must use threads, tasks, co-routines, or whatever concurrency is called in your language.
#Kotlin
Kotlin
// version 1.1.2   import java.util.concurrent.CyclicBarrier   class DelayedMessagePrinter(val barrier: CyclicBarrier, val msg: String) : Runnable { override fun run() { barrier.await() println(msg) } }   fun main(args: Array<String>) { val msgs = listOf("Enjoy", "Rosetta", "Code") val barrier = CyclicBarrier(msgs.size) for (msg in msgs) Thread(DelayedMessagePrinter(barrier, msg)).start() }
http://rosettacode.org/wiki/Compile-time_calculation
Compile-time calculation
Some programming languages allow calculation of values at compile time. Task Calculate   10!   (ten factorial)   at compile time. Print the result when the program is run. Discuss what limitations apply to compile-time calculations in your language.
#Ada
Ada
  with Ada.Text_Io; procedure CompileTimeCalculation is Factorial : constant Integer := 10*9*8*7*6*5*4*3*2*1;   begin Ada.Text_Io.Put(Integer'Image(Factorial)); end CompileTimeCalculation;  
http://rosettacode.org/wiki/Compile-time_calculation
Compile-time calculation
Some programming languages allow calculation of values at compile time. Task Calculate   10!   (ten factorial)   at compile time. Print the result when the program is run. Discuss what limitations apply to compile-time calculations in your language.
#AppleScript
AppleScript
-- This handler must be declared somewhere above the relevant property declaration -- so that the compiler knows about it when compiling the property. on factorial(n) set f to 1 repeat with i from 2 to n set f to f * i end repeat   return f end factorial   property compiledValue : factorial(10) -- Or of course simply: -- property compiledValue : 2 * 3 * 4 * 5 * 6 * 7 * 8 * 9 * 10   on run return compiledValue end run
http://rosettacode.org/wiki/Compile-time_calculation
Compile-time calculation
Some programming languages allow calculation of values at compile time. Task Calculate   10!   (ten factorial)   at compile time. Print the result when the program is run. Discuss what limitations apply to compile-time calculations in your language.
#BASIC
BASIC
CONST factorial10 = 2 * 3 * 4 * 5 * 6 * 7 * 8 * 9 * 10
http://rosettacode.org/wiki/Conjugate_transpose
Conjugate transpose
Suppose that a matrix M {\displaystyle M} contains complex numbers. Then the conjugate transpose of M {\displaystyle M} is a matrix M H {\displaystyle M^{H}} containing the complex conjugates of the matrix transposition of M {\displaystyle M} . ( M H ) j i = M i j ¯ {\displaystyle (M^{H})_{ji}={\overline {M_{ij}}}} This means that row j {\displaystyle j} , column i {\displaystyle i} of the conjugate transpose equals the complex conjugate of row i {\displaystyle i} , column j {\displaystyle j} of the original matrix. In the next list, M {\displaystyle M} must also be a square matrix. A Hermitian matrix equals its own conjugate transpose: M H = M {\displaystyle M^{H}=M} . A normal matrix is commutative in multiplication with its conjugate transpose: M H M = M M H {\displaystyle M^{H}M=MM^{H}} . A unitary matrix has its inverse equal to its conjugate transpose: M H = M − 1 {\displaystyle M^{H}=M^{-1}} . This is true iff M H M = I n {\displaystyle M^{H}M=I_{n}} and iff M M H = I n {\displaystyle MM^{H}=I_{n}} , where I n {\displaystyle I_{n}} is the identity matrix. Task Given some matrix of complex numbers, find its conjugate transpose. Also determine if the matrix is a: Hermitian matrix, normal matrix, or unitary matrix. See also MathWorld entry: conjugate transpose MathWorld entry: Hermitian matrix MathWorld entry: normal matrix MathWorld entry: unitary matrix
#Sidef
Sidef
func is_Hermitian (Array m, Array t) -> Bool { m == t }   func mat_mult (Array a, Array b, Number ε = -3) { var p = [] for r, c in (^a ~X ^b[0]) { for k in (^b) { p[r][c] := 0 += (a[r][k] * b[k][c]) -> round!(ε) } } return p }   func mat_trans (Array m) { var r = [] for i,j in (^m ~X ^m[0]) { r[j][i] = m[i][j] } return r }   func mat_ident (Number n) { ^n -> map {|i| [i.of(0)..., 1, (n - i - 1).of(0)...] } }   func is_Normal (Array m, Array t) -> Bool { mat_mult(m, t) == mat_mult(t, m) }   func is_Unitary (Array m, Array t) -> Bool { mat_mult(m, t) == mat_ident(m.len) }   func say_it (Array a) { a.each {|b| b.map { "%9s" % _ }.join(' ').say } }   [ [ [ 1, 1+1i, 2i], [1-1i, 5, -3], [0-2i, -3, 0] ], [ [1, 1, 0], [0, 1, 1], [1, 0, 1] ], [ [0.707 , 0.707, 0], [0.707i, -0.707i, 0], [0 , 0, 1i] ] ].each { |m| say "\nMatrix:" say_it(m) var t = mat_trans(m.map{.map{.conj}}) say "\nTranspose:" say_it(t) say "Is Hermitian?\t#{is_Hermitian(m, t)}" say "Is Normal?\t#{is_Normal(m, t)}" say "Is Unitary?\t#{is_Unitary(m, t)}" }
http://rosettacode.org/wiki/Compound_data_type
Compound data type
Data Structure This illustrates a data structure, a means of storing data within a program. You may see other such structures in the Data Structures category. Task Create a compound data type: Point(x,y) A compound data type is one that holds multiple independent values. Related task   Enumeration See also Array Associative array: Creation, Iteration Collections Compound data type Doubly-linked list: Definition, Element definition, Element insertion, List Traversal, Element Removal Linked list Queue: Definition, Usage Set Singly-linked list: Element definition, Element insertion, List Traversal, Element Removal Stack
#F.23
F#
type Point = { x : int; y : int }   let points = [ {x = 1; y = 1}; {x = 5; y = 5} ]   Seq.iter (fun p -> printfn "%d,%d" p.x p.y) points
http://rosettacode.org/wiki/Compound_data_type
Compound data type
Data Structure This illustrates a data structure, a means of storing data within a program. You may see other such structures in the Data Structures category. Task Create a compound data type: Point(x,y) A compound data type is one that holds multiple independent values. Related task   Enumeration See also Array Associative array: Creation, Iteration Collections Compound data type Doubly-linked list: Definition, Element definition, Element insertion, List Traversal, Element Removal Linked list Queue: Definition, Usage Set Singly-linked list: Element definition, Element insertion, List Traversal, Element Removal Stack
#Factor
Factor
TUPLE: point x y ;
http://rosettacode.org/wiki/Continued_fraction
Continued fraction
continued fraction Mathworld a 0 + b 1 a 1 + b 2 a 2 + b 3 a 3 + ⋱ {\displaystyle a_{0}+{\cfrac {b_{1}}{a_{1}+{\cfrac {b_{2}}{a_{2}+{\cfrac {b_{3}}{a_{3}+\ddots }}}}}}} The task is to write a program which generates such a number and prints a real representation of it. The code should be tested by calculating and printing the square root of 2, Napier's Constant, and Pi, using the following coefficients: For the square root of 2, use a 0 = 1 {\displaystyle a_{0}=1} then a N = 2 {\displaystyle a_{N}=2} . b N {\displaystyle b_{N}} is always 1 {\displaystyle 1} . 2 = 1 + 1 2 + 1 2 + 1 2 + ⋱ {\displaystyle {\sqrt {2}}=1+{\cfrac {1}{2+{\cfrac {1}{2+{\cfrac {1}{2+\ddots }}}}}}} For Napier's Constant, use a 0 = 2 {\displaystyle a_{0}=2} , then a N = N {\displaystyle a_{N}=N} . b 1 = 1 {\displaystyle b_{1}=1} then b N = N − 1 {\displaystyle b_{N}=N-1} . e = 2 + 1 1 + 1 2 + 2 3 + 3 4 + ⋱ {\displaystyle e=2+{\cfrac {1}{1+{\cfrac {1}{2+{\cfrac {2}{3+{\cfrac {3}{4+\ddots }}}}}}}}} For Pi, use a 0 = 3 {\displaystyle a_{0}=3} then a N = 6 {\displaystyle a_{N}=6} . b N = ( 2 N − 1 ) 2 {\displaystyle b_{N}=(2N-1)^{2}} . π = 3 + 1 6 + 9 6 + 25 6 + ⋱ {\displaystyle \pi =3+{\cfrac {1}{6+{\cfrac {9}{6+{\cfrac {25}{6+\ddots }}}}}}} See also   Continued fraction/Arithmetic for tasks that do arithmetic over continued fractions.
#Scheme
Scheme
#!r6rs (import (rnrs base (6)) (srfi :41 streams))   (define nats (stream-cons 0 (stream-map (lambda (x) (+ x 1)) nats)))   (define (build-stream fn) (stream-map fn nats))   (define (stream-cycle s . S) (cond ((stream-null? (car S)) stream-null) (else (stream-cons (stream-car s) (apply stream-cycle (append S (list (stream-cdr s))))))))   (define (cf-floor cf) (stream-car cf)) (define (cf-num cf) (stream-car (stream-cdr cf))) (define (cf-denom cf) (stream-cdr (stream-cdr cf)))   (define (cf-integer? x) (stream-null? (stream-cdr x)))   (define (cf->real x) (let refine ((x x) (n 65536)) (cond ((= n 0) +inf.0) ((cf-integer? x) (cf-floor x)) (else (+ (cf-floor x) (/ (cf-num x) (refine (cf-denom x) (- n 1))))))))   (define (real->cf x) (let-values (((integer-part fractional-part) (div-and-mod x 1))) (if (= fractional-part 0.0) (stream (exact integer-part)) (stream-cons (exact integer-part) (stream-cons 1 (real->cf (/ fractional-part)))))))     (define sqrt2 (stream-cons 1 (stream-constant 1 2)))   (define napier (stream-append (stream 2 1) (stream-cycle (stream-cdr nats) (stream-cdr nats))))   (define pi (stream-cons 3 (stream-cycle (build-stream (lambda (n) (expt (- (* 2 (+ n 1)) 1) 2))) (stream-constant 6))))
http://rosettacode.org/wiki/Copy_a_string
Copy a string
This task is about copying a string. Task Where it is relevant, distinguish between copying the contents of a string versus making an additional reference to an existing string. Other tasks related to string operations: Metrics Array length String length Copy a string Empty string  (assignment) Counting Word frequency Letter frequency Jewels and stones I before E except after C Bioinformatics/base count Count occurrences of a substring Count how many vowels and consonants occur in a string Remove/replace XXXX redacted Conjugate a Latin verb Remove vowels from a string String interpolation (included) Strip block comments Strip comments from a string Strip a set of characters from a string Strip whitespace from a string -- top and tail Strip control codes and extended characters from a string Anagrams/Derangements/shuffling Word wheel ABC problem Sattolo cycle Knuth shuffle Ordered words Superpermutation minimisation Textonyms (using a phone text pad) Anagrams Anagrams/Deranged anagrams Permutations/Derangements Find/Search/Determine ABC words Odd words Word ladder Semordnilap Word search Wordiff  (game) String matching Tea cup rim text Alternade words Changeable words State name puzzle String comparison Unique characters Unique characters in each string Extract file extension Levenshtein distance Palindrome detection Common list elements Longest common suffix Longest common prefix Compare a list of strings Longest common substring Find common directory path Words from neighbour ones Change e letters to i in words Non-continuous subsequences Longest common subsequence Longest palindromic substrings Longest increasing subsequence Words containing "the" substring Sum of the digits of n is substring of n Determine if a string is numeric Determine if a string is collapsible Determine if a string is squeezable Determine if a string has all unique characters Determine if a string has all the same characters Longest substrings without repeating characters Find words which contains all the vowels Find words which contains most consonants Find words which contains more than 3 vowels Find words which first and last three letters are equals Find words which odd letters are consonants and even letters are vowels or vice_versa Formatting Substring Rep-string Word wrap String case Align columns Literals/String Repeat a string Brace expansion Brace expansion using ranges Reverse a string Phrase reversals Comma quibbling Special characters String concatenation Substring/Top and tail Commatizing numbers Reverse words in a string Suffixation of decimal numbers Long literals, with continuations Numerical and alphabetical suffixes Abbreviations, easy Abbreviations, simple Abbreviations, automatic Song lyrics/poems/Mad Libs/phrases Mad Libs Magic 8-ball 99 Bottles of Beer The Name Game (a song) The Old lady swallowed a fly The Twelve Days of Christmas Tokenize Text between Tokenize a string Word break problem Tokenize a string with escaping Split a character string based on change of character Sequences Show ASCII table De Bruijn sequences Self-referential sequences Generate lower case ASCII alphabet
#PostScript
PostScript
(hello) dup length string copy
http://rosettacode.org/wiki/Copy_a_string
Copy a string
This task is about copying a string. Task Where it is relevant, distinguish between copying the contents of a string versus making an additional reference to an existing string. Other tasks related to string operations: Metrics Array length String length Copy a string Empty string  (assignment) Counting Word frequency Letter frequency Jewels and stones I before E except after C Bioinformatics/base count Count occurrences of a substring Count how many vowels and consonants occur in a string Remove/replace XXXX redacted Conjugate a Latin verb Remove vowels from a string String interpolation (included) Strip block comments Strip comments from a string Strip a set of characters from a string Strip whitespace from a string -- top and tail Strip control codes and extended characters from a string Anagrams/Derangements/shuffling Word wheel ABC problem Sattolo cycle Knuth shuffle Ordered words Superpermutation minimisation Textonyms (using a phone text pad) Anagrams Anagrams/Deranged anagrams Permutations/Derangements Find/Search/Determine ABC words Odd words Word ladder Semordnilap Word search Wordiff  (game) String matching Tea cup rim text Alternade words Changeable words State name puzzle String comparison Unique characters Unique characters in each string Extract file extension Levenshtein distance Palindrome detection Common list elements Longest common suffix Longest common prefix Compare a list of strings Longest common substring Find common directory path Words from neighbour ones Change e letters to i in words Non-continuous subsequences Longest common subsequence Longest palindromic substrings Longest increasing subsequence Words containing "the" substring Sum of the digits of n is substring of n Determine if a string is numeric Determine if a string is collapsible Determine if a string is squeezable Determine if a string has all unique characters Determine if a string has all the same characters Longest substrings without repeating characters Find words which contains all the vowels Find words which contains most consonants Find words which contains more than 3 vowels Find words which first and last three letters are equals Find words which odd letters are consonants and even letters are vowels or vice_versa Formatting Substring Rep-string Word wrap String case Align columns Literals/String Repeat a string Brace expansion Brace expansion using ranges Reverse a string Phrase reversals Comma quibbling Special characters String concatenation Substring/Top and tail Commatizing numbers Reverse words in a string Suffixation of decimal numbers Long literals, with continuations Numerical and alphabetical suffixes Abbreviations, easy Abbreviations, simple Abbreviations, automatic Song lyrics/poems/Mad Libs/phrases Mad Libs Magic 8-ball 99 Bottles of Beer The Name Game (a song) The Old lady swallowed a fly The Twelve Days of Christmas Tokenize Text between Tokenize a string Word break problem Tokenize a string with escaping Split a character string based on change of character Sequences Show ASCII table De Bruijn sequences Self-referential sequences Generate lower case ASCII alphabet
#PowerShell
PowerShell
$str = "foo" $dup = $str
http://rosettacode.org/wiki/Constrained_random_points_on_a_circle
Constrained random points on a circle
Task Generate 100 <x,y> coordinate pairs such that x and y are integers sampled from the uniform distribution with the condition that 10 ≤ x 2 + y 2 ≤ 15 {\displaystyle 10\leq {\sqrt {x^{2}+y^{2}}}\leq 15} . Then display/plot them. The outcome should be a "fuzzy" circle. The actual number of points plotted may be less than 100, given that some pairs may be generated more than once. There are several possible approaches to accomplish this. Here are two possible algorithms. 1) Generate random pairs of integers and filter out those that don't satisfy this condition: 10 ≤ x 2 + y 2 ≤ 15 {\displaystyle 10\leq {\sqrt {x^{2}+y^{2}}}\leq 15} . 2) Precalculate the set of all possible points (there are 404 of them) and select randomly from this set.
#Mathematica_.2F_Wolfram_Language
Mathematica / Wolfram Language
sample = Take[Cases[RandomInteger[{-15, 15}, {500, 2}], {x_, y_} /; 10 <= Sqrt[x^2 + y^2] <= 15], 100];   Show[{RegionPlot[10 <= Sqrt[x^2 + y^2] <= 15, {x, -16, 16}, {y, -16, 16}, Axes -> True], ListPlot[sample]}]
http://rosettacode.org/wiki/Convex_hull
Convex hull
Find the points which form a convex hull from a set of arbitrary two dimensional points. For example, given the points (16,3), (12,17), (0,6), (-4,-6), (16,6), (16,-7), (16,-3), (17,-4), (5,19), (19,-8), (3,16), (12,13), (3,-4), (17,5), (-3,15), (-3,-9), (0,11), (-9,-3), (-4,-2) and (12,10) the convex hull would be (-9,-3), (-3,-9), (19,-8), (17,5), (12,17), (5,19) and (-3,15). See also Convex Hull (youtube) http://www.geeksforgeeks.org/convex-hull-set-2-graham-scan/
#REXX
REXX
/* REXX --------------------------------------------------------------- * Compute the Convex Hull for a set of points * Format of the input file: * (16,3) (12,17) (0,6) (-4,-6) (16,6) (16,-7) (16,-3) (17,-4) (5,19) * (19,-8) (3,16) (12,13) (3,-4) (17,5) (-3,15) (-3,-9) (0,11) (-9,-3) * (-4,-2) *--------------------------------------------------------------------*/ Signal On Novalue Signal On Syntax Parse Arg fid If fid='' Then Do fid='chullmin.in' /* miscellaneous test data */ fid='chullx.in' fid='chullt.in' fid='chulla.in' fid='chullxx.in' fid='sq.in' fid='tri.in' fid='line.in' fid='point.in' fid='chull.in' /* data from task description */ End g.0debug='' g.0oid=fn(fid)'.txt'; 'erase' g.0oid x.=0 yl.='' Parse Value '1000 -1000' With g.0xmin g.0xmax Parse Value '1000 -1000' With g.0ymin g.0ymax /*--------------------------------------------------------------------- * First read the input and store the points' coordinates * x.0 contains the number of points, x.i contains the x.coordinate * yl.x contains the y.coordinate(s) of points (x/y) *--------------------------------------------------------------------*/ Do while lines(fid)>0 l=linein(fid) Do While l<>'' Parse Var l '(' x ',' y ')' l Call store x,y End End Call lineout fid Do i=1 To x.0 /* loop over points */ x=x.i yl.x=sortv(yl.x) /* sort y-coordinates */ End Call sho   /*--------------------------------------------------------------------- * Now we look for special border points: * lefthigh and leftlow: leftmost points with higheste and lowest y * ritehigh and ritelow: rightmost points with higheste and lowest y * yl.x contains the y.coordinate(s) of points (x/y) *--------------------------------------------------------------------*/ leftlow=0 lefthigh=0 Do i=1 To x.0 x=x.i If maxv(yl.x)=g.0ymax Then Do If lefthigh=0 Then lefthigh=x'/'g.0ymax ritehigh=x'/'g.0ymax End If minv(yl.x)=g.0ymin Then Do ritelow=x'/'g.0ymin If leftlow=0 Then leftlow=x'/'g.0ymin End End Call o 'lefthigh='lefthigh Call o 'ritehigh='ritehigh Call o 'ritelow ='ritelow Call o 'leftlow ='leftlow /*--------------------------------------------------------------------- * Now we look for special border points: * leftmost_n and leftmost_s: points with lowest x and highest/lowest y * ritemost_n and ritemost_s: points with largest x and highest/lowest y * n and s stand foNorth and South, respectively *--------------------------------------------------------------------*/ x=g.0xmi; leftmost_n=x'/'maxv(yl.x) x=g.0xmi; leftmost_s=x'/'minv(yl.x) x=g.0xma; ritemost_n=x'/'maxv(yl.x) x=g.0xma; ritemost_s=x'/'minv(yl.x)   /*--------------------------------------------------------------------- * Now we compute the paths from ritehigh to ritelow (n_end) * and leftlow to lefthigh (s_end), respectively *--------------------------------------------------------------------*/ x=g.0xma n_end='' Do i=words(yl.x) To 1 By -1 n_end=n_end x'/'word(yl.x,i) End Call o 'n_end='n_end x=g.0xmi s_end='' Do i=1 To words(yl.x) s_end=s_end x'/'word(yl.x,i) End Call o 's_end='s_end   n_high='' s_low='' /*--------------------------------------------------------------------- * Now we compute the upper part of the convex hull (nhull) *--------------------------------------------------------------------*/ Call o 'leftmost_n='leftmost_n Call o 'lefthigh ='lefthigh nhull=leftmost_n res=mk_nhull(leftmost_n,lefthigh); nhull=nhull res Call o 'A nhull='nhull Do While res<>lefthigh res=mk_nhull(res,lefthigh); nhull=nhull res Call o 'B nhull='nhull End res=mk_nhull(lefthigh,ritemost_n); nhull=nhull res Call o 'C nhull='nhull Do While res<>ritemost_n res=mk_nhull(res,ritemost_n); nhull=nhull res Call o 'D nhull='nhull End   nhull=nhull n_end /* attach the right vertical border */   /*--------------------------------------------------------------------- * Now we compute the lower part of the convex hull (shull) *--------------------------------------------------------------------*/ res=mk_shull(ritemost_s,ritelow); shull=ritemost_s res Call o 'A shull='shull Do While res<>ritelow res=mk_shull(res,ritelow) shull=shull res Call o 'B shull='shull End res=mk_shull(ritelow,leftmost_s) shull=shull res Call o 'C shull='shull Do While res<>leftmost_s res=mk_shull(res,leftmost_s); shull=shull res Call o 'D shull='shull End   shull=shull s_end   chull=nhull shull /* concatenate upper and lower part */ /* eliminate duplicates */ /* too lazy to take care before :-) */ Parse Var chull chullx chull have.=0 have.chullx=1 Do i=1 By 1 While chull>'' Parse Var chull xy chull If have.xy=0 Then Do chullx=chullx xy have.xy=1 End End /* show the result */ Say 'Points of convex hull in clockwise order:' Say chullx /********************************************************************** * steps that were necessary in previous attempts /*--------------------------------------------------------------------- * Final polish: Insert points that are not yet in chullx but should be * First on the upper hull going from left to right *--------------------------------------------------------------------*/ i=1 Do While i<words(chullx) xya=word(chullx,i)  ; Parse Var xya xa '/' ya If xa=g.0xmax Then Leave xyb=word(chullx,i+1); Parse Var xyb xb '/' yb Do j=1 To x.0 If x.j>xa Then Do If x.j<xb Then Do xx=x.j parse Value kdx(xya,xyb) With k d x If (k*xx+d)=maxv(yl.xx) Then Do chullx=subword(chullx,1,i) xx'/'maxv(yl.xx), subword(chullx,i+1) i=i+1 End End End Else i=i+1 End End   Say chullx   /*--------------------------------------------------------------------- * Final polish: Insert points that are not yet in chullx but should be * Then on the lower hull going from right to left *--------------------------------------------------------------------*/ i=wordpos(ritemost_s,chullx) Do While i<words(chullx) xya=word(chullx,i)  ; Parse Var xya xa '/' ya If xa=g.0xmin Then Leave xyb=word(chullx,i+1); Parse Var xyb xb '/' yb Do j=x.0 To 1 By -1 If x.j<xa Then Do If x.j>xb Then Do xx=x.j parse Value kdx(xya,xyb) With k d x If (k*xx+d)=minv(yl.xx) Then Do chullx=subword(chullx,1,i) xx'/'minv(yl.xx), subword(chullx,i+1) i=i+1 End End End Else i=i+1 End End Say chullx **********************************************************************/ Call lineout g.0oid   Exit   store: Procedure Expose x. yl. g. /*--------------------------------------------------------------------- * arrange the points in ascending order of x (in x.) and, * for each x in ascending order of y (in yl.x) * g.0xmin is the smallest x-value, etc. * g.0xmi is the x-coordinate * g.0ymin is the smallest y-value, etc. * g.0ymi is the x-coordinate of such a point *--------------------------------------------------------------------*/ Parse Arg x,y Call o 'store' x y If x<g.0xmin Then Do; g.0xmin=x; g.0xmi=x; End If x>g.0xmax Then Do; g.0xmax=x; g.0xma=x; End If y<g.0ymin Then Do; g.0ymin=y; g.0ymi=x; End If y>g.0ymax Then Do; g.0ymax=y; g.0yma=x; End Do i=1 To x.0 Select When x.i>x Then Leave When x.i=x Then Do yl.x=yl.x y Return End Otherwise Nop End End Do j=x.0 To i By -1 ja=j+1 x.ja=x.j End x.i=x yl.x=y x.0=x.0+1 Return   sho: Procedure Expose x. yl. g. Do i=1 To x.0 x=x.i say format(i,2) 'x='format(x,3) 'yl='yl.x End Say '' Return   maxv: Procedure Expose g. Call trace 'O' Parse Arg l res=-1000 Do While l<>'' Parse Var l v l If v>res Then res=v End Return res   minv: Procedure Expose g. Call trace 'O' Parse Arg l res=1000 Do While l<>'' Parse Var l v l If v<res Then res=v End Return res   sortv: Procedure Expose g. Call trace 'O' Parse Arg l res='' Do Until l='' v=minv(l) res=res v l=remove(v,l) End Return space(res)   lastword: return word(arg(1),words(arg(1)))   kdx: Procedure Expose xy. g. /*--------------------------------------------------------------------- * Compute slope and y-displacement of a straight line * that is defined by two points: y=k*x+d * Specialty; k='*' x=xa if xb=xa *--------------------------------------------------------------------*/ Call trace 'O' Parse Arg xya,xyb Parse Var xya xa '/' ya Parse Var xyb xb '/' yb If xa=xb Then Parse Value '*' '-' xa With k d x Else Do k=(yb-ya)/(xb-xa) d=yb-k*xb x='*' End Return k d x   remove: /*--------------------------------------------------------------------- * Remove a specified element (e) from a given string (s) *--------------------------------------------------------------------*/ Parse Arg e,s Parse Var s sa (e) sb Return space(sa sb)   o: Procedure Expose g. /*--------------------------------------------------------------------- * Write a line to the debug file *--------------------------------------------------------------------*/ If arg(2)=1 Then say arg(1) Return lineout(g.0oid,arg(1))   is_ok: Procedure Expose x. yl. g. sigl /*--------------------------------------------------------------------- * Test if a given point (b) is above/on/or below a straight line * defined by two points (a and c) *--------------------------------------------------------------------*/ Parse Arg a,b,c,op Call o 'is_ok' a b c op Parse Value kdx(a,c) With k d x Parse Var b x'/'y If op='U' Then y=maxv(yl.x) Else y=minv(yl.x) Call o y x (k*x+d) If (abs(y-(k*x+d))<1.e-8) Then Return 0 If op='U' Then res=(y<=(k*x+d)) Else res=(y>=(k*x+d)) Return res   mk_nhull: Procedure Expose x. yl. g. /*--------------------------------------------------------------------- * Compute the upper (north) hull between two points (xya and xyb) * Move x from xyb back to xya until all points within the current * range (x and xyb) are BELOW the straight line defined xya and x * Then make x the new starting point *--------------------------------------------------------------------*/ Parse Arg xya,xyb Call o 'mk_nhull' xya xyb If xya=xyb Then Return xya Parse Var xya xa '/' ya Parse Var xyb xb '/' yb iu=0 iv=0 Do xi=1 To x.0 if x.xi>=xa & iu=0 Then iu=xi if x.xi<=xb Then iv=xi If x.xi>xb Then Leave End Call o iu iv xu=x.iu xyu=xu'/'maxv(yl.xu) Do h=iv To iu+1 By -1 Until good Call o 'iv='iv,g.0debug Call o ' h='h,g.0debug xh=x.h xyh=xh'/'maxv(yl.xh) Call o 'Testing' xyu xyh,g.0debug good=1 Do hh=h-1 To iu+1 By -1 While good xhh=x.hh xyhh=xhh'/'maxv(yl.xhh) Call o 'iu hh iv=' iu hh h,g.0debug If is_ok(xyu,xyhh,xyh,'U') Then Do Call o xyhh 'is under' xyu xyh,g.0debug Nop End Else Do good=0 Call o xyhh 'is above' xyu xyh '-' xyh 'ist nicht gut' End End End Call o xyh 'is the one'   Return xyh   p: Return Say arg(1) Pull . Return   mk_shull: Procedure Expose x. yl. g. /*--------------------------------------------------------------------- * Compute the lower (south) hull between two points (xya and xyb) * Move x from xyb back to xya until all points within the current * range (x and xyb) are ABOVE the straight line defined xya and x * Then make x the new starting point *----- ---------------------------------------------------------------*/ Parse Arg xya,xyb Call o 'mk_shull' xya xyb If xya=xyb Then Return xya Parse Var xya xa '/' ya Parse Var xyb xb '/' yb iu=0 iv=0 Do xi=x.0 To 1 By -1 if x.xi<=xa & iu=0 Then iu=xi if x.xi>=xb Then iv=xi If x.xi<xb Then Leave End Call o iu iv '_' x.iu x.iv Call o 'mk_shull iv iu' iv iu xu=x.iu xyu=xu'/'minv(yl.xu) good=0 Do h=iv To iu-1 Until good xh=x.h xyh=xh'/'minv(yl.xh) Call o 'Testing' xyu xyh h iu good=1 Do hh=h+1 To iu-1 While good Call o 'iu hh h=' iu hh h xhh=x.hh xyhh=xhh'/'minv(yl.xhh) If is_ok(xyu,xyhh,xyh,'O') Then Do Call o xyhh 'is above' xyu xyh Nop End Else Do Call o xyhh 'is under' xyu xyh '-' xyh 'ist nicht gut' good=0 End End End Call o xyh 'is the one' Return xyh   Novalue: Say 'Novalue raised in line' sigl Say sourceline(sigl) Say 'Variable' condition('D') Signal lookaround   Syntax: Say 'Syntax raised in line' sigl Say sourceline(sigl) Say 'rc='rc '('errortext(rc)')'   halt: lookaround: Say 'You can look around now.' Trace ?R Nop Exit 12
http://rosettacode.org/wiki/Convert_seconds_to_compound_duration
Convert seconds to compound duration
Task Write a function or program which:   takes a positive integer representing a duration in seconds as input (e.g., 100), and   returns a string which shows the same duration decomposed into:   weeks,   days,   hours,   minutes,   and   seconds. This is detailed below (e.g., "2 hr, 59 sec"). Demonstrate that it passes the following three test-cases: Test Cases input number output string 7259 2 hr, 59 sec 86400 1 d 6000000 9 wk, 6 d, 10 hr, 40 min Details The following five units should be used: unit suffix used in output conversion week wk 1 week = 7 days day d 1 day = 24 hours hour hr 1 hour = 60 minutes minute min 1 minute = 60 seconds second sec However, only include quantities with non-zero values in the output (e.g., return "1 d" and not "0 wk, 1 d, 0 hr, 0 min, 0 sec"). Give larger units precedence over smaller ones as much as possible (e.g., return 2 min, 10 sec and not 1 min, 70 sec or 130 sec) Mimic the formatting shown in the test-cases (quantities sorted from largest unit to smallest and separated by comma+space; value and unit of each quantity separated by space).
#Scheme
Scheme
  (import (scheme base) (scheme write) (srfi 1) (only (srfi 13) string-join))   (define *seconds-in-minute* 60) (define *seconds-in-hour* (* 60 *seconds-in-minute*)) (define *seconds-in-day* (* 24 *seconds-in-hour*)) (define *seconds-in-week* (* 7 *seconds-in-day*))   (define (seconds->duration seconds) (define (format val unit) (if (zero? val) "" (string-append (number->string val) " " unit))) (let*-values (((weeks wk-remainder) (floor/ seconds *seconds-in-week*)) ((days dy-remainder) (floor/ wk-remainder *seconds-in-day*)) ((hours hr-remainder) (floor/ dy-remainder *seconds-in-hour*)) ((minutes mn-remainder) (floor/ hr-remainder *seconds-in-minute*))) (string-join (delete "" (list (format weeks "wk") (format days "d") (format hours "hr") (format minutes "min") (format mn-remainder "sec")) string=?) ", ")))   (display (seconds->duration 7259)) (newline) (display (seconds->duration 86400)) (newline) (display (seconds->duration 6000000)) (newline)  
http://rosettacode.org/wiki/Concurrent_computing
Concurrent computing
Task Using either native language concurrency syntax or freely available libraries, write a program to display the strings "Enjoy" "Rosetta" "Code", one string per line, in random order. Concurrency syntax must use threads, tasks, co-routines, or whatever concurrency is called in your language.
#LFE
LFE
  ;;; ;;; This is a straight port of the Erlang version. ;;; ;;; You can run this under the LFE REPL as follows: ;;; ;;; (slurp "concurrent-computing.lfe") ;;; (start) ;;; (defmodule concurrent-computing (export (start 0)))   (defun start () (lc ((<- word '("Enjoy" "Rosetta" "Code"))) (spawn (lambda () (say (self) word)))) (wait 2) 'ok)   (defun say (pid word) (lfe_io:format "~p~n" (list word)) (! pid 'done))   (defun wait (n) (receive ('done (case n (0 0) (_n (wait (- n 1)))))))  
http://rosettacode.org/wiki/Concurrent_computing
Concurrent computing
Task Using either native language concurrency syntax or freely available libraries, write a program to display the strings "Enjoy" "Rosetta" "Code", one string per line, in random order. Concurrency syntax must use threads, tasks, co-routines, or whatever concurrency is called in your language.
#Logtalk
Logtalk
:- object(concurrency).   :- initialization(output).   output :- threaded(( write('Enjoy'), write('Rosetta'), write('Code') )).   :- end_object.
http://rosettacode.org/wiki/Compile-time_calculation
Compile-time calculation
Some programming languages allow calculation of values at compile time. Task Calculate   10!   (ten factorial)   at compile time. Print the result when the program is run. Discuss what limitations apply to compile-time calculations in your language.
#C
C
#include <stdio.h> #include <order/interpreter.h>   #define ORDER_PP_DEF_8fac ORDER_PP_FN( \ 8fn(8X, 8seq_fold(8times, 1, 8seq_iota(1, 8inc(8X)))) )   int main(void) { printf("10! = %d\n", ORDER_PP( 8to_lit( 8fac(10) ) ) ); return 0; }
http://rosettacode.org/wiki/Compile-time_calculation
Compile-time calculation
Some programming languages allow calculation of values at compile time. Task Calculate   10!   (ten factorial)   at compile time. Print the result when the program is run. Discuss what limitations apply to compile-time calculations in your language.
#C.23
C#
using System;   public static class Program { public const int FACTORIAL_10 = 10 * 9 * 8 * 7 * 6 * 5 * 4 * 3 * 2 * 1; static void Main() { Console.WriteLine(FACTORIAL_10); } }
http://rosettacode.org/wiki/Compile-time_calculation
Compile-time calculation
Some programming languages allow calculation of values at compile time. Task Calculate   10!   (ten factorial)   at compile time. Print the result when the program is run. Discuss what limitations apply to compile-time calculations in your language.
#C.2B.2B
C++
#include <iostream>   template<int i> struct Fac { static const int result = i * Fac<i-1>::result; };   template<> struct Fac<1> { static const int result = 1; };     int main() { std::cout << "10! = " << Fac<10>::result << "\n"; return 0; }
http://rosettacode.org/wiki/Conjugate_transpose
Conjugate transpose
Suppose that a matrix M {\displaystyle M} contains complex numbers. Then the conjugate transpose of M {\displaystyle M} is a matrix M H {\displaystyle M^{H}} containing the complex conjugates of the matrix transposition of M {\displaystyle M} . ( M H ) j i = M i j ¯ {\displaystyle (M^{H})_{ji}={\overline {M_{ij}}}} This means that row j {\displaystyle j} , column i {\displaystyle i} of the conjugate transpose equals the complex conjugate of row i {\displaystyle i} , column j {\displaystyle j} of the original matrix. In the next list, M {\displaystyle M} must also be a square matrix. A Hermitian matrix equals its own conjugate transpose: M H = M {\displaystyle M^{H}=M} . A normal matrix is commutative in multiplication with its conjugate transpose: M H M = M M H {\displaystyle M^{H}M=MM^{H}} . A unitary matrix has its inverse equal to its conjugate transpose: M H = M − 1 {\displaystyle M^{H}=M^{-1}} . This is true iff M H M = I n {\displaystyle M^{H}M=I_{n}} and iff M M H = I n {\displaystyle MM^{H}=I_{n}} , where I n {\displaystyle I_{n}} is the identity matrix. Task Given some matrix of complex numbers, find its conjugate transpose. Also determine if the matrix is a: Hermitian matrix, normal matrix, or unitary matrix. See also MathWorld entry: conjugate transpose MathWorld entry: Hermitian matrix MathWorld entry: normal matrix MathWorld entry: unitary matrix
#Sparkling
Sparkling
# Computes conjugate transpose of M let conjTransp = function conjTransp(M) { return map(range(sizeof M[0]), function(row) { return map(range(sizeof M), function(col) { return cplx_conj(M[col][row]); }); }); };   # Helper for cplxMatMul let cplxVecScalarMul = function cplxVecScalarMul(A, B, row, col) { var M = { "re": 0.0, "im": 0.0 }; let N = sizeof A; for (var i = 0; i < N; i++) { let P = cplx_mul(A[row][i], B[i][col]); M = cplx_add(M, P); } return M; };   # Multiplies matrices A and B # A and B are assumed to be square and of the same size, # this condition is not checked. let cplxMatMul = function cplxMatMul(A, B) { var R = {}; let N = sizeof A; for (var row = 0; row < N; row++) { R[row] = {}; for (var col = 0; col < N; col++) { R[row][col] = cplxVecScalarMul(A, B, row, col); } } return R; };   # Helper for creating an array representing a complex number # given its textual representation let _ = function makeComplex(str) { let sep = indexof(str, "+", 1); if sep < 0 { sep = indexof(str, "-", 1); } let reStr = substrto(str, sep); let imStr = substrfrom(str, sep); return { "re": tofloat(reStr), "im": tofloat(imStr) }; };   # Formats a complex matrix let printCplxMat = function printCplxMat(M) { foreach(M, function(i, row) { foreach(row, function(j, elem) { printf("  %.2f%+.2fi", elem.re, elem.im); }); print(); }); };   # A Hermitian matrix let H = { { _("3+0i"), _("2+1i") }, { _("2-1i"), _("0+0i") } };   # A normal matrix let N = { { _("1+0i"), _("1+0i"), _("0+0i") }, { _("0+0i"), _("1+0i"), _("1+0i") }, { _("1+0i"), _("0+0i"), _("1+0i") } };   # A unitary matrix let U = { { _("0.70710678118+0i"), _("0.70710678118+0i"), _("0+0i") }, { _("0-0.70710678118i"), _("0+0.70710678118i"), _("0+0i") }, { _("0+0i"), _("0+0i"), _("0+1i") } };     print("Hermitian matrix:\nH = "); printCplxMat(H); print("H* = "); printCplxMat(conjTransp(H)); print();   print("Normal matrix:\nN = "); printCplxMat(N); print("N* = "); printCplxMat(conjTransp(N)); print("N* x N = "); printCplxMat(cplxMatMul(conjTransp(N), N)); print("N x N* = "); printCplxMat(cplxMatMul(N, conjTransp(N))); print();   print("Unitary matrix:\nU = "); printCplxMat(U); print("U* = "); printCplxMat(conjTransp(U)); print("U x U* = "); printCplxMat(cplxMatMul(U, conjTransp(U))); print();
http://rosettacode.org/wiki/Conjugate_transpose
Conjugate transpose
Suppose that a matrix M {\displaystyle M} contains complex numbers. Then the conjugate transpose of M {\displaystyle M} is a matrix M H {\displaystyle M^{H}} containing the complex conjugates of the matrix transposition of M {\displaystyle M} . ( M H ) j i = M i j ¯ {\displaystyle (M^{H})_{ji}={\overline {M_{ij}}}} This means that row j {\displaystyle j} , column i {\displaystyle i} of the conjugate transpose equals the complex conjugate of row i {\displaystyle i} , column j {\displaystyle j} of the original matrix. In the next list, M {\displaystyle M} must also be a square matrix. A Hermitian matrix equals its own conjugate transpose: M H = M {\displaystyle M^{H}=M} . A normal matrix is commutative in multiplication with its conjugate transpose: M H M = M M H {\displaystyle M^{H}M=MM^{H}} . A unitary matrix has its inverse equal to its conjugate transpose: M H = M − 1 {\displaystyle M^{H}=M^{-1}} . This is true iff M H M = I n {\displaystyle M^{H}M=I_{n}} and iff M M H = I n {\displaystyle MM^{H}=I_{n}} , where I n {\displaystyle I_{n}} is the identity matrix. Task Given some matrix of complex numbers, find its conjugate transpose. Also determine if the matrix is a: Hermitian matrix, normal matrix, or unitary matrix. See also MathWorld entry: conjugate transpose MathWorld entry: Hermitian matrix MathWorld entry: normal matrix MathWorld entry: unitary matrix
#Stata
Stata
  : a=1,2i\3i,4   : a 1 2 +-----------+ 1 | 1 2i | 2 | 3i 4 | +-----------+   : a' 1 2 +-------------+ 1 | 1 -3i | 2 | -2i 4 | +-------------+   : transposeonly(a) 1 2 +-----------+ 1 | 1 3i | 2 | 2i 4 | +-----------+   : a*a'==a'*a 0   : a'==a 0   : a'*a==I(rows(a)) 0  
http://rosettacode.org/wiki/Compound_data_type
Compound data type
Data Structure This illustrates a data structure, a means of storing data within a program. You may see other such structures in the Data Structures category. Task Create a compound data type: Point(x,y) A compound data type is one that holds multiple independent values. Related task   Enumeration See also Array Associative array: Creation, Iteration Collections Compound data type Doubly-linked list: Definition, Element definition, Element insertion, List Traversal, Element Removal Linked list Queue: Definition, Usage Set Singly-linked list: Element definition, Element insertion, List Traversal, Element Removal Stack
#Fantom
Fantom
  // define a class to contain the two fields // accessors to get/set the field values are automatically generated class Point { Int x Int y }   class Main { public static Void main () { // empty constructor, so x,y set to 0 point1 := Point() // constructor uses with-block, to initialise values point2 := Point { x = 1; y = 2} echo ("Point 1 = (" + point1.x + ", " + point1.y + ")") echo ("Point 2 = (" + point2.x + ", " + point2.y + ")") } }  
http://rosettacode.org/wiki/Compound_data_type
Compound data type
Data Structure This illustrates a data structure, a means of storing data within a program. You may see other such structures in the Data Structures category. Task Create a compound data type: Point(x,y) A compound data type is one that holds multiple independent values. Related task   Enumeration See also Array Associative array: Creation, Iteration Collections Compound data type Doubly-linked list: Definition, Element definition, Element insertion, List Traversal, Element Removal Linked list Queue: Definition, Usage Set Singly-linked list: Element definition, Element insertion, List Traversal, Element Removal Stack
#Forth
Forth
: pt>x ( point -- x ) ; : pt>y ( point -- y ) CELL+ ; : .pt ( point -- ) dup pt>x @ . pt>y @ . ; \ or for this simple structure, 2@ . .   create point 6 , 0 , 7 point pt>y ! .pt \ 6 7
http://rosettacode.org/wiki/Continued_fraction
Continued fraction
continued fraction Mathworld a 0 + b 1 a 1 + b 2 a 2 + b 3 a 3 + ⋱ {\displaystyle a_{0}+{\cfrac {b_{1}}{a_{1}+{\cfrac {b_{2}}{a_{2}+{\cfrac {b_{3}}{a_{3}+\ddots }}}}}}} The task is to write a program which generates such a number and prints a real representation of it. The code should be tested by calculating and printing the square root of 2, Napier's Constant, and Pi, using the following coefficients: For the square root of 2, use a 0 = 1 {\displaystyle a_{0}=1} then a N = 2 {\displaystyle a_{N}=2} . b N {\displaystyle b_{N}} is always 1 {\displaystyle 1} . 2 = 1 + 1 2 + 1 2 + 1 2 + ⋱ {\displaystyle {\sqrt {2}}=1+{\cfrac {1}{2+{\cfrac {1}{2+{\cfrac {1}{2+\ddots }}}}}}} For Napier's Constant, use a 0 = 2 {\displaystyle a_{0}=2} , then a N = N {\displaystyle a_{N}=N} . b 1 = 1 {\displaystyle b_{1}=1} then b N = N − 1 {\displaystyle b_{N}=N-1} . e = 2 + 1 1 + 1 2 + 2 3 + 3 4 + ⋱ {\displaystyle e=2+{\cfrac {1}{1+{\cfrac {1}{2+{\cfrac {2}{3+{\cfrac {3}{4+\ddots }}}}}}}}} For Pi, use a 0 = 3 {\displaystyle a_{0}=3} then a N = 6 {\displaystyle a_{N}=6} . b N = ( 2 N − 1 ) 2 {\displaystyle b_{N}=(2N-1)^{2}} . π = 3 + 1 6 + 9 6 + 25 6 + ⋱ {\displaystyle \pi =3+{\cfrac {1}{6+{\cfrac {9}{6+{\cfrac {25}{6+\ddots }}}}}}} See also   Continued fraction/Arithmetic for tasks that do arithmetic over continued fractions.
#Sidef
Sidef
func continued_fraction(a, b, f, n = 1000, r = 1) { f(func (r) { r < n ? (a(r) / (b(r) + __FUNC__(r+1))) : 0 }(r)) }   var params = Hash( "φ" => [ { 1 }, { 1 }, { 1 + _ } ], "√2" => [ { 1 }, { 2 }, { 1 + _ } ], "e" => [ { _ }, { _ }, { 1 + 1/_ } ], "π" => [ { (2*_ - 1)**2 }, { 6 }, { 3 + _ } ], "τ" => [ { _**2 }, { 2*_ + 1 }, { 8 / (1 + _) } ], )   for k in (params.keys.sort) { printf("%2s ≈ %s\n", k, continued_fraction(params{k}...)) }
http://rosettacode.org/wiki/Copy_a_string
Copy a string
This task is about copying a string. Task Where it is relevant, distinguish between copying the contents of a string versus making an additional reference to an existing string. Other tasks related to string operations: Metrics Array length String length Copy a string Empty string  (assignment) Counting Word frequency Letter frequency Jewels and stones I before E except after C Bioinformatics/base count Count occurrences of a substring Count how many vowels and consonants occur in a string Remove/replace XXXX redacted Conjugate a Latin verb Remove vowels from a string String interpolation (included) Strip block comments Strip comments from a string Strip a set of characters from a string Strip whitespace from a string -- top and tail Strip control codes and extended characters from a string Anagrams/Derangements/shuffling Word wheel ABC problem Sattolo cycle Knuth shuffle Ordered words Superpermutation minimisation Textonyms (using a phone text pad) Anagrams Anagrams/Deranged anagrams Permutations/Derangements Find/Search/Determine ABC words Odd words Word ladder Semordnilap Word search Wordiff  (game) String matching Tea cup rim text Alternade words Changeable words State name puzzle String comparison Unique characters Unique characters in each string Extract file extension Levenshtein distance Palindrome detection Common list elements Longest common suffix Longest common prefix Compare a list of strings Longest common substring Find common directory path Words from neighbour ones Change e letters to i in words Non-continuous subsequences Longest common subsequence Longest palindromic substrings Longest increasing subsequence Words containing "the" substring Sum of the digits of n is substring of n Determine if a string is numeric Determine if a string is collapsible Determine if a string is squeezable Determine if a string has all unique characters Determine if a string has all the same characters Longest substrings without repeating characters Find words which contains all the vowels Find words which contains most consonants Find words which contains more than 3 vowels Find words which first and last three letters are equals Find words which odd letters are consonants and even letters are vowels or vice_versa Formatting Substring Rep-string Word wrap String case Align columns Literals/String Repeat a string Brace expansion Brace expansion using ranges Reverse a string Phrase reversals Comma quibbling Special characters String concatenation Substring/Top and tail Commatizing numbers Reverse words in a string Suffixation of decimal numbers Long literals, with continuations Numerical and alphabetical suffixes Abbreviations, easy Abbreviations, simple Abbreviations, automatic Song lyrics/poems/Mad Libs/phrases Mad Libs Magic 8-ball 99 Bottles of Beer The Name Game (a song) The Old lady swallowed a fly The Twelve Days of Christmas Tokenize Text between Tokenize a string Word break problem Tokenize a string with escaping Split a character string based on change of character Sequences Show ASCII table De Bruijn sequences Self-referential sequences Generate lower case ASCII alphabet
#ProDOS
ProDOS
editvar /newvar /value=a /userinput=1 /title=Enter a string to be copied: editvar /newvar /value=b /userinput=1 /title=Enter current directory of the string: editvar /newvar /value=c /userinput=1 /title=Enter file to copy to: copy -a- from -b- to -c-
http://rosettacode.org/wiki/Copy_a_string
Copy a string
This task is about copying a string. Task Where it is relevant, distinguish between copying the contents of a string versus making an additional reference to an existing string. Other tasks related to string operations: Metrics Array length String length Copy a string Empty string  (assignment) Counting Word frequency Letter frequency Jewels and stones I before E except after C Bioinformatics/base count Count occurrences of a substring Count how many vowels and consonants occur in a string Remove/replace XXXX redacted Conjugate a Latin verb Remove vowels from a string String interpolation (included) Strip block comments Strip comments from a string Strip a set of characters from a string Strip whitespace from a string -- top and tail Strip control codes and extended characters from a string Anagrams/Derangements/shuffling Word wheel ABC problem Sattolo cycle Knuth shuffle Ordered words Superpermutation minimisation Textonyms (using a phone text pad) Anagrams Anagrams/Deranged anagrams Permutations/Derangements Find/Search/Determine ABC words Odd words Word ladder Semordnilap Word search Wordiff  (game) String matching Tea cup rim text Alternade words Changeable words State name puzzle String comparison Unique characters Unique characters in each string Extract file extension Levenshtein distance Palindrome detection Common list elements Longest common suffix Longest common prefix Compare a list of strings Longest common substring Find common directory path Words from neighbour ones Change e letters to i in words Non-continuous subsequences Longest common subsequence Longest palindromic substrings Longest increasing subsequence Words containing "the" substring Sum of the digits of n is substring of n Determine if a string is numeric Determine if a string is collapsible Determine if a string is squeezable Determine if a string has all unique characters Determine if a string has all the same characters Longest substrings without repeating characters Find words which contains all the vowels Find words which contains most consonants Find words which contains more than 3 vowels Find words which first and last three letters are equals Find words which odd letters are consonants and even letters are vowels or vice_versa Formatting Substring Rep-string Word wrap String case Align columns Literals/String Repeat a string Brace expansion Brace expansion using ranges Reverse a string Phrase reversals Comma quibbling Special characters String concatenation Substring/Top and tail Commatizing numbers Reverse words in a string Suffixation of decimal numbers Long literals, with continuations Numerical and alphabetical suffixes Abbreviations, easy Abbreviations, simple Abbreviations, automatic Song lyrics/poems/Mad Libs/phrases Mad Libs Magic 8-ball 99 Bottles of Beer The Name Game (a song) The Old lady swallowed a fly The Twelve Days of Christmas Tokenize Text between Tokenize a string Word break problem Tokenize a string with escaping Split a character string based on change of character Sequences Show ASCII table De Bruijn sequences Self-referential sequences Generate lower case ASCII alphabet
#Prolog
Prolog
?- A = "A test string", A = B. A = B, B = "A test string".
http://rosettacode.org/wiki/Constrained_random_points_on_a_circle
Constrained random points on a circle
Task Generate 100 <x,y> coordinate pairs such that x and y are integers sampled from the uniform distribution with the condition that 10 ≤ x 2 + y 2 ≤ 15 {\displaystyle 10\leq {\sqrt {x^{2}+y^{2}}}\leq 15} . Then display/plot them. The outcome should be a "fuzzy" circle. The actual number of points plotted may be less than 100, given that some pairs may be generated more than once. There are several possible approaches to accomplish this. Here are two possible algorithms. 1) Generate random pairs of integers and filter out those that don't satisfy this condition: 10 ≤ x 2 + y 2 ≤ 15 {\displaystyle 10\leq {\sqrt {x^{2}+y^{2}}}\leq 15} . 2) Precalculate the set of all possible points (there are 404 of them) and select randomly from this set.
#MATLAB
MATLAB
function [xCoordinates,yCoordinates] = randomDisc(numPoints)   xCoordinates = []; yCoordinates = [];   %Helper function that samples a random integer from the uniform %distribution between -15 and 15. function nums = randInt(n) nums = round((31*rand(n,1))-15.5); end   n = numPoints;   while n > 0   x = randInt(n); y = randInt(n);   norms = sqrt((x.^2) + (y.^2)); inBounds = find((10 <= norms) & (norms <= 15));   xCoordinates = [xCoordinates; x(inBounds)]; yCoordinates = [yCoordinates; y(inBounds)];   n = numPoints - numel(xCoordinates); end   xCoordinates(numPoints+1:end) = []; yCoordinates(numPoints+1:end) = [];   end
http://rosettacode.org/wiki/Convex_hull
Convex hull
Find the points which form a convex hull from a set of arbitrary two dimensional points. For example, given the points (16,3), (12,17), (0,6), (-4,-6), (16,6), (16,-7), (16,-3), (17,-4), (5,19), (19,-8), (3,16), (12,13), (3,-4), (17,5), (-3,15), (-3,-9), (0,11), (-9,-3), (-4,-2) and (12,10) the convex hull would be (-9,-3), (-3,-9), (19,-8), (17,5), (12,17), (5,19) and (-3,15). See also Convex Hull (youtube) http://www.geeksforgeeks.org/convex-hull-set-2-graham-scan/
#Ruby
Ruby
class Point include Comparable attr :x, :y   def initialize(x, y) @x = x @y = y end   def <=>(other) x <=> other.x end   def to_s "(%d, %d)" % [@x, @y] end   def to_str to_s() end end   def ccw(a, b, c) ((b.x - a.x) * (c.y - a.y)) > ((b.y - a.y) * (c.x - a.x)) end   def convexHull(p) if p.length == 0 then return [] end   p = p.sort h = []   # Lower hull p.each { |pt| while h.length >= 2 and not ccw(h[-2], h[-1], pt) h.pop() end h << pt }   # upper hull t = h.length + 1 p.reverse.each { |pt| while h.length >= t and not ccw(h[-2], h[-1], pt) h.pop() end h << pt }   h.pop() h end   def main points = [ Point.new(16, 3), Point.new(12, 17), Point.new( 0, 6), Point.new(-4, -6), Point.new(16, 6), Point.new(16, -7), Point.new(16, -3), Point.new(17, -4), Point.new( 5, 19), Point.new(19, -8), Point.new( 3, 16), Point.new(12, 13), Point.new( 3, -4), Point.new(17, 5), Point.new(-3, 15), Point.new(-3, -9), Point.new( 0, 11), Point.new(-9, -3), Point.new(-4, -2), Point.new(12, 10) ] hull = convexHull(points) print "Convex Hull: [", hull.join(", "), "]\n" end   main()
http://rosettacode.org/wiki/Convert_seconds_to_compound_duration
Convert seconds to compound duration
Task Write a function or program which:   takes a positive integer representing a duration in seconds as input (e.g., 100), and   returns a string which shows the same duration decomposed into:   weeks,   days,   hours,   minutes,   and   seconds. This is detailed below (e.g., "2 hr, 59 sec"). Demonstrate that it passes the following three test-cases: Test Cases input number output string 7259 2 hr, 59 sec 86400 1 d 6000000 9 wk, 6 d, 10 hr, 40 min Details The following five units should be used: unit suffix used in output conversion week wk 1 week = 7 days day d 1 day = 24 hours hour hr 1 hour = 60 minutes minute min 1 minute = 60 seconds second sec However, only include quantities with non-zero values in the output (e.g., return "1 d" and not "0 wk, 1 d, 0 hr, 0 min, 0 sec"). Give larger units precedence over smaller ones as much as possible (e.g., return 2 min, 10 sec and not 1 min, 70 sec or 130 sec) Mimic the formatting shown in the test-cases (quantities sorted from largest unit to smallest and separated by comma+space; value and unit of each quantity separated by space).
#Sidef
Sidef
func polymod(n, *divs) { gather { divs.each { |i| var m = take(n % i) (n -= m) /= i } take(n) } }   func compound_duration(seconds) { (polymod(seconds, 60, 60, 24, 7) ~Z <sec min hr d wk>).grep { |a| a[0] > 0 }.reverse.map{.join(' ')}.join(', ') }   [7259, 86400, 6000000].each { |s| say "#{'%7d' % s} sec = #{compound_duration(s)}" }