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http://rosettacode.org/wiki/Comments
Comments
Task Show all ways to include text in a language source file that's completely ignored by the compiler or interpreter. Related tasks   Documentation   Here_document See also   Wikipedia   xkcd (Humor: hand gesture denoting // for "commenting out" people.)
#Visual_Basic
Visual Basic
'comment Rem comment #If 0 Technically not a comment; the compiler may or may not ignore this, but the IDE won't. Note the somewhat odd formatting seen here; the IDE will likely just mark the entire line(s) as errors. #End If
http://rosettacode.org/wiki/Comments
Comments
Task Show all ways to include text in a language source file that's completely ignored by the compiler or interpreter. Related tasks   Documentation   Here_document See also   Wikipedia   xkcd (Humor: hand gesture denoting // for "commenting out" people.)
#Visual_Basic_.NET
Visual Basic .NET
' This is a comment REM This is also a comment Dim comment as string ' You can also append comments to statements Dim comment2 as string REM You can append comments to statements
http://rosettacode.org/wiki/Comments
Comments
Task Show all ways to include text in a language source file that's completely ignored by the compiler or interpreter. Related tasks   Documentation   Here_document See also   Wikipedia   xkcd (Humor: hand gesture denoting // for "commenting out" people.)
#Visual_Objects
Visual Objects
  // This is a comment /* This is a comment */ * This is a comment && This is a comment NOTE This is a commen * This is a comment && This is a comment NOTE This is a commen    
http://rosettacode.org/wiki/Chowla_numbers
Chowla numbers
Chowla numbers are also known as:   Chowla's function   chowla numbers   the chowla function   the chowla number   the chowla sequence The chowla number of   n   is   (as defined by Chowla's function):   the sum of the divisors of   n     excluding unity and   n   where   n   is a positive integer The s...
#Ada
Ada
with Ada.Text_IO;   procedure Chowla_Numbers is   function Chowla (N : Positive) return Natural is Sum : Natural  := 0; I  : Positive := 2; J  : Positive; begin while I * I <= N loop if N mod I = 0 then J  := N / I; Sum := Sum + I + (if I = J then 0 else...
http://rosettacode.org/wiki/Church_numerals
Church numerals
Task In the Church encoding of natural numbers, the number N is encoded by a function that applies its first argument N times to its second argument. Church zero always returns the identity function, regardless of its first argument. In other words, the first argument is not applied to the second argument at all. C...
#Erlang
Erlang
-module(church). -export([main/1, zero/1]). zero(_) -> fun(F) -> F end. succ(N) -> fun(F) -> fun(X) -> F((N(F))(X)) end end. add(N,M) -> fun(F) -> fun(X) -> (M(F))((N(F))(X)) end end. mult(N,M) -> fun(F) -> fun(X) -> (M(N(F)))(X) end end. power(B,E) -> E(B).   to_int(C) -> CountUp = fun(I) -> I + 1 end, (C(Cou...
http://rosettacode.org/wiki/Classes
Classes
In object-oriented programming class is a set (a transitive closure) of types bound by the relation of inheritance. It is said that all types derived from some base type T and the type T itself form a class T. The first type T from the class T sometimes is called the root type of the class. A class of types itself, a...
#Clojure
Clojure
  ; You can think of this as an interface (defprotocol Foo (getFoo [this]))   ; Generates Example1 Class with foo as field, with method that returns foo. (defrecord Example1 [foo] Foo (getFoo [this] foo))   ; Create instance and invoke our method to return field value (-> (Example1. "Hi") .getFoo) "Hi"
http://rosettacode.org/wiki/Classes
Classes
In object-oriented programming class is a set (a transitive closure) of types bound by the relation of inheritance. It is said that all types derived from some base type T and the type T itself form a class T. The first type T from the class T sometimes is called the root type of the class. A class of types itself, a...
#COBOL
COBOL
IDENTIFICATION DIVISION. CLASS-ID. my-class INHERITS base.   *> The 'INHERITS base' and the following ENVIRONMENT DIVISION *> are optional (in Visual COBOL). ENVIRONMENT DIVISION. CONFIGURATION SECTION. REPOSITORY. CLASS base.   *> There is no way (...
http://rosettacode.org/wiki/Cistercian_numerals
Cistercian numerals
Cistercian numerals were used across Europe by Cistercian monks during the Late Medieval Period as an alternative to Roman numerals. They were used to represent base 10 integers from 0 to 9999. How they work All Cistercian numerals begin with a vertical line segment, which by itself represents the number 0. Then, glyp...
#Julia
Julia
using Gtk, Cairo   const can = GtkCanvas(800, 100) const win = GtkWindow(can, "Canvas") const numbers = [0, 1, 20, 300, 4000, 5555, 6789, 8123]   function drawcnum(ctx, xypairs) move_to(ctx, xypairs[1][1], xypairs[1][2]) for p in xypairs[2:end] line_to(ctx, p[1], p[2]) end stroke(ctx) end   @gua...
http://rosettacode.org/wiki/Cistercian_numerals
Cistercian numerals
Cistercian numerals were used across Europe by Cistercian monks during the Late Medieval Period as an alternative to Roman numerals. They were used to represent base 10 integers from 0 to 9999. How they work All Cistercian numerals begin with a vertical line segment, which by itself represents the number 0. Then, glyp...
#Kotlin
Kotlin
import java.io.StringWriter   class Cistercian() { constructor(number: Int) : this() { draw(number) }   private val size = 15 private var canvas = Array(size) { Array(size) { ' ' } }   init { initN() }   private fun initN() { for (row in canvas) { row.fill...
http://rosettacode.org/wiki/Closest-pair_problem
Closest-pair problem
This page uses content from Wikipedia. The original article was at Closest pair of points problem. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance) Task Provide a function to find the closest two p...
#D
D
import std.stdio, std.typecons, std.math, std.algorithm, std.random, std.traits, std.range, std.complex;   auto bruteForceClosestPair(T)(in T[] points) pure nothrow @nogc { // return pairwise(points.length.iota, points.length.iota) // .reduce!(min!((i, j) => abs(points[i] - points[j]))); auto minD = U...
http://rosettacode.org/wiki/Closures/Value_capture
Closures/Value capture
Task Create a list of ten functions, in the simplest manner possible   (anonymous functions are encouraged),   such that the function at index   i   (you may choose to start   i   from either   0   or   1),   when run, should return the square of the index,   that is,   i 2. Display the result of runnin...
#JavaScript
JavaScript
var funcs = []; for (var i = 0; i < 10; i++) { funcs.push( (function(i) { return function() { return i * i; } })(i) ); } window.alert(funcs[3]()); // alerts "9"
http://rosettacode.org/wiki/Circular_primes
Circular primes
Definitions A circular prime is a prime number with the property that the number generated at each intermediate step when cyclically permuting its (base 10) digits will also be prime. For example: 1193 is a circular prime, since 1931, 9311 and 3119 are all also prime. Note that a number which is a cyclic permutation ...
#Pascal
Pascal
  program CircularPrimes; //nearly the way it is done: //http://www.worldofnumbers.com/circular.htm //base 4 counter to create numbers with first digit is the samallest used. //check if numbers are tested before and reduce gmp-calls by checking with prime 3,7   {$IFDEF FPC} {$MODE DELPHI}{$OPTIMIZATION ON,ALL} us...
http://rosettacode.org/wiki/Collections
Collections
This task has been clarified. Its programming examples are in need of review to ensure that they still fit the requirements of the task. Collections are abstractions to represent sets of values. In statically-typed languages, the values are typically of a common data type. Task Create a collection, and add a fe...
#COBOL
COBOL
identification division. program-id. collections.   data division. working-storage section. 01 sample-table. 05 sample-record occurs 1 to 3 times depending on the-index. 10 sample-alpha pic x(4). 10 filler pic x value ":". 10 ...
http://rosettacode.org/wiki/Combinations
Combinations
Task Given non-negative integers   m   and   n,   generate all size   m   combinations   of the integers from   0   (zero)   to   n-1   in sorted order   (each combination is sorted and the entire table is sorted). Example 3   comb   5     is: 0 1 2 0 1 3 0 1 4 0 2 3 0 2 4 0 3 4 1 2 3 1 2 4 1 3 4 2 3 4 ...
#Java
Java
import java.util.Collections; import java.util.LinkedList;   public class Comb{   public static void main(String[] args){ System.out.println(comb(3,5)); }   public static String bitprint(int u){ String s= ""; for(int n= 0;u > 0;++n, u>>= 1) ...
http://rosettacode.org/wiki/Conditional_structures
Conditional structures
Control Structures These are examples of control structures. You may also be interested in: Conditional structures Exceptions Flow-control structures Loops Task List the conditional structures offered by a programming language. See Wikipedia: conditionals for descriptions. Common conditional structures include ...
#PicoLisp
PicoLisp
(if (condition) # If the condition evaluates to non-NIL (then-do-this) # Then execute the following expression (else-do-that) # Else execute all other expressions (and-more) )   (ifn (condition) # If the condition evaluates to NIL (then-do-this)...
http://rosettacode.org/wiki/Comments
Comments
Task Show all ways to include text in a language source file that's completely ignored by the compiler or interpreter. Related tasks   Documentation   Here_document See also   Wikipedia   xkcd (Humor: hand gesture denoting // for "commenting out" people.)
#Vlang
Vlang
// This is a single line comment. /* This is a multiline comment. /* It can be nested. */ */
http://rosettacode.org/wiki/Comments
Comments
Task Show all ways to include text in a language source file that's completely ignored by the compiler or interpreter. Related tasks   Documentation   Here_document See also   Wikipedia   xkcd (Humor: hand gesture denoting // for "commenting out" people.)
#Vorpal
Vorpal
# single line comment
http://rosettacode.org/wiki/Comments
Comments
Task Show all ways to include text in a language source file that's completely ignored by the compiler or interpreter. Related tasks   Documentation   Here_document See also   Wikipedia   xkcd (Humor: hand gesture denoting // for "commenting out" people.)
#Wart
Wart
# single-line comment
http://rosettacode.org/wiki/Chernick%27s_Carmichael_numbers
Chernick's Carmichael numbers
In 1939, Jack Chernick proved that, for n ≥ 3 and m ≥ 1: U(n, m) = (6m + 1) * (12m + 1) * Product_{i=1..n-2} (2^i * 9m + 1) is a Carmichael number if all the factors are primes and, for n > 4, m is a multiple of 2^(n-4). Example U(3, m) = (6m + 1) * (12m + 1) * (18m + 1) U(4, m) = U(3, m) * (2^2 * 9m + 1)...
#C
C
#include <stdio.h> #include <stdlib.h> #include <gmp.h>   typedef unsigned long long int u64;   #define TRUE 1 #define FALSE 0   int primality_pretest(u64 k) { if (!(k % 3) || !(k % 5) || !(k % 7) || !(k % 11) || !(k % 13) || !(k % 17) || !(k % 19) || !(k % 23)) return (k <= 23); return TRUE; }   int probpri...
http://rosettacode.org/wiki/Chowla_numbers
Chowla numbers
Chowla numbers are also known as:   Chowla's function   chowla numbers   the chowla function   the chowla number   the chowla sequence The chowla number of   n   is   (as defined by Chowla's function):   the sum of the divisors of   n     excluding unity and   n   where   n   is a positive integer The s...
#ALGOL_68
ALGOL 68
BEGIN # find some Chowla numbers ( Chowla n = sum of divisors of n exclusing n and 1 ) # # returs the Chowla number of n # PROC chowla = ( INT n )INT: BEGIN INT sum := 0; FOR i FROM 2 WHILE i * i <= n DO IF n MOD i = 0 THEN INT j = n OVER ...
http://rosettacode.org/wiki/Church_numerals
Church numerals
Task In the Church encoding of natural numbers, the number N is encoded by a function that applies its first argument N times to its second argument. Church zero always returns the identity function, regardless of its first argument. In other words, the first argument is not applied to the second argument at all. C...
#F.23
F#
type IChurch = abstract Apply : ('a -> 'a) -> ('a -> 'a)   let zeroChurch = { new IChurch with override __.Apply _ = id } let oneChurch = { new IChurch with override __.Apply f = f } let succChurch (n: IChurch) = { new IChurch with override __.Apply f = fun x -> f (n.Apply f x) } let addChurch (m: IChurch) (n: IChu...
http://rosettacode.org/wiki/Classes
Classes
In object-oriented programming class is a set (a transitive closure) of types bound by the relation of inheritance. It is said that all types derived from some base type T and the type T itself form a class T. The first type T from the class T sometimes is called the root type of the class. A class of types itself, a...
#Coco
Coco
class Rectangle # The constructor is defined as a bare function. This # constructor accepts one argument and automatically assigns it # to an instance variable. (@width) ->   # Another instance variable. length: 10   # A method. area: -> @width * @length   # Instantiate the class using the 'new' ope...
http://rosettacode.org/wiki/Classes
Classes
In object-oriented programming class is a set (a transitive closure) of types bound by the relation of inheritance. It is said that all types derived from some base type T and the type T itself form a class T. The first type T from the class T sometimes is called the root type of the class. A class of types itself, a...
#CoffeeScript
CoffeeScript
# Create a basic class class Rectangle # Constructor that accepts one argument constructor: (@width) ->   # An instance variable length: 10   # A method area: () -> @width * @length   # Instantiate the class using the new operator rect = new Rectangle 2
http://rosettacode.org/wiki/Cistercian_numerals
Cistercian numerals
Cistercian numerals were used across Europe by Cistercian monks during the Late Medieval Period as an alternative to Roman numerals. They were used to represent base 10 integers from 0 to 9999. How they work All Cistercian numerals begin with a vertical line segment, which by itself represents the number 0. Then, glyp...
#Lua
Lua
function initN() local n = {} for i=1,15 do n[i] = {} for j=1,11 do n[i][j] = " " end n[i][6] = "x" end return n end   function horiz(n, c1, c2, r) for c=c1,c2 do n[r+1][c+1] = "x" end end   function verti(n, r1, r2, c) for r=r1,r2 do ...
http://rosettacode.org/wiki/Closest-pair_problem
Closest-pair problem
This page uses content from Wikipedia. The original article was at Closest pair of points problem. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance) Task Provide a function to find the closest two p...
#Delphi
Delphi
defmodule Closest_pair do # brute-force algorithm: def bruteForce([p0,p1|_] = points), do: bf_loop(points, {distance(p0, p1), {p0, p1}})   defp bf_loop([_], acc), do: acc defp bf_loop([h|t], acc), do: bf_loop(t, bf_loop(h, t, acc))   defp bf_loop(_, [], acc), do: acc defp bf_loop(p0, [p1|t], {minD, minP}) d...
http://rosettacode.org/wiki/Closures/Value_capture
Closures/Value capture
Task Create a list of ten functions, in the simplest manner possible   (anonymous functions are encouraged),   such that the function at index   i   (you may choose to start   i   from either   0   or   1),   when run, should return the square of the index,   that is,   i 2. Display the result of runnin...
#Julia
Julia
funcs = [ () -> i^2 for i = 1:10 ]
http://rosettacode.org/wiki/Closures/Value_capture
Closures/Value capture
Task Create a list of ten functions, in the simplest manner possible   (anonymous functions are encouraged),   such that the function at index   i   (you may choose to start   i   from either   0   or   1),   when run, should return the square of the index,   that is,   i 2. Display the result of runnin...
#Kotlin
Kotlin
// version 1.0.6   fun main(args: Array<String>) { // create an array of 10 anonymous functions which return the square of their index val funcs = Array(10){ fun(): Int = it * it } // call all but the last (0 .. 8).forEach { println(funcs[it]()) } }
http://rosettacode.org/wiki/Circular_primes
Circular primes
Definitions A circular prime is a prime number with the property that the number generated at each intermediate step when cyclically permuting its (base 10) digits will also be prime. For example: 1193 is a circular prime, since 1931, 9311 and 3119 are all also prime. Note that a number which is a cyclic permutation ...
#Perl
Perl
use strict; use warnings; use feature 'say'; use List::Util 'min'; use ntheory 'is_prime';   sub rotate { my($i,@a) = @_; join '', @a[$i .. @a-1, 0 .. $i-1] }   sub isCircular { my ($n) = @_; return 0 unless is_prime($n); my @circular = split //, $n; return 0 if min(@circular) < $circular[0]; for (1...
http://rosettacode.org/wiki/Collections
Collections
This task has been clarified. Its programming examples are in need of review to ensure that they still fit the requirements of the task. Collections are abstractions to represent sets of values. In statically-typed languages, the values are typically of a common data type. Task Create a collection, and add a fe...
#Common_Lisp
Common Lisp
CL-USER> (let ((list '()) (hash-table (make-hash-table))) (push 1 list) (push 2 list) (push 3 list) (format t "~S~%" (reverse list)) (setf (gethash 'foo hash-table) 42) (setf (gethash 'bar hash-table) 69) (maphash (lambda (key v...
http://rosettacode.org/wiki/Combinations
Combinations
Task Given non-negative integers   m   and   n,   generate all size   m   combinations   of the integers from   0   (zero)   to   n-1   in sorted order   (each combination is sorted and the entire table is sorted). Example 3   comb   5     is: 0 1 2 0 1 3 0 1 4 0 2 3 0 2 4 0 3 4 1 2 3 1 2 4 1 3 4 2 3 4 ...
#JavaScript
JavaScript
function bitprint(u) { var s=""; for (var n=0; u; ++n, u>>=1) if (u&1) s+=n+" "; return s; } function bitcount(u) { for (var n=0; u; ++n, u=u&(u-1)); return n; } function comb(c,n) { var s=[]; for (var u=0; u<1<<n; u++) if (bitcount(u)==c) s.push(bitprint(u)) return s.sort(); } comb(3,5)
http://rosettacode.org/wiki/Conditional_structures
Conditional structures
Control Structures These are examples of control structures. You may also be interested in: Conditional structures Exceptions Flow-control structures Loops Task List the conditional structures offered by a programming language. See Wikipedia: conditionals for descriptions. Common conditional structures include ...
#PL.2FI
PL/I
if condition_exp then unique_statement; else unique_statement;   if condition_exp then unique_statement; else unique_statement;   if condition_exp then do; list_of_statements; end; else do; list_of_statements; end;
http://rosettacode.org/wiki/Comments
Comments
Task Show all ways to include text in a language source file that's completely ignored by the compiler or interpreter. Related tasks   Documentation   Here_document See also   Wikipedia   xkcd (Humor: hand gesture denoting // for "commenting out" people.)
#Wren
Wren
// This is a line comment. /* This is a single line block comment.*/ /* This is a multi-line block comment.*/ /* This is/* a nested */block comment.*/
http://rosettacode.org/wiki/Comments
Comments
Task Show all ways to include text in a language source file that's completely ignored by the compiler or interpreter. Related tasks   Documentation   Here_document See also   Wikipedia   xkcd (Humor: hand gesture denoting // for "commenting out" people.)
#X10
X10
// This is a single line comment   /* This comment spans multiple lines */
http://rosettacode.org/wiki/Comments
Comments
Task Show all ways to include text in a language source file that's completely ignored by the compiler or interpreter. Related tasks   Documentation   Here_document See also   Wikipedia   xkcd (Humor: hand gesture denoting // for "commenting out" people.)
#XLISP
XLISP
; this is a comment
http://rosettacode.org/wiki/Chernick%27s_Carmichael_numbers
Chernick's Carmichael numbers
In 1939, Jack Chernick proved that, for n ≥ 3 and m ≥ 1: U(n, m) = (6m + 1) * (12m + 1) * Product_{i=1..n-2} (2^i * 9m + 1) is a Carmichael number if all the factors are primes and, for n > 4, m is a multiple of 2^(n-4). Example U(3, m) = (6m + 1) * (12m + 1) * (18m + 1) U(4, m) = U(3, m) * (2^2 * 9m + 1)...
#C.2B.2B
C++
#include <gmp.h> #include <iostream>   using namespace std;   typedef unsigned long long int u64;   bool primality_pretest(u64 k) { // for k > 23   if (!(k % 3) || !(k % 5) || !(k % 7) || !(k % 11) || !(k % 13) || !(k % 17) || !(k % 19) || !(k % 23) ) { return (k <= 23); }   retur...
http://rosettacode.org/wiki/Chowla_numbers
Chowla numbers
Chowla numbers are also known as:   Chowla's function   chowla numbers   the chowla function   the chowla number   the chowla sequence The chowla number of   n   is   (as defined by Chowla's function):   the sum of the divisors of   n     excluding unity and   n   where   n   is a positive integer The s...
#Arturo
Arturo
chowla: function [n]-> sum remove remove factors n 1 n countPrimesUpTo: function [limit][ count: 1 loop 3.. .step: 2 limit 'x [ if zero? chowla x -> count: count + 1 ] return count ]   loop 1..37 'i -> print [i "=>" chowla i] print ""   loop [100 1000 10000 100000 1000000 10000000] 'lim [ pr...
http://rosettacode.org/wiki/Church_numerals
Church numerals
Task In the Church encoding of natural numbers, the number N is encoded by a function that applies its first argument N times to its second argument. Church zero always returns the identity function, regardless of its first argument. In other words, the first argument is not applied to the second argument at all. C...
#F.C5.8Drmul.C3.A6
Fōrmulæ
package main   import "fmt"   type any = interface{}   type fn func(any) any   type church func(fn) fn   func zero(f fn) fn { return func(x any) any { return x } }   func (c church) succ() church { return func(f fn) fn { return func(x any) any { return f(c(f)(x)) } } ...
http://rosettacode.org/wiki/Classes
Classes
In object-oriented programming class is a set (a transitive closure) of types bound by the relation of inheritance. It is said that all types derived from some base type T and the type T itself form a class T. The first type T from the class T sometimes is called the root type of the class. A class of types itself, a...
#Common_Lisp
Common Lisp
(defclass circle () ((radius :initarg :radius :initform 1.0 :type number :reader radius)))   (defmethod area ((shape circle)) (* pi (expt (radius shape) 2)))   > (defvar *c* (make-instance 'circle :radius 2)) > (area *c*) 12.566370614359172d0
http://rosettacode.org/wiki/Cistercian_numerals
Cistercian numerals
Cistercian numerals were used across Europe by Cistercian monks during the Late Medieval Period as an alternative to Roman numerals. They were used to represent base 10 integers from 0 to 9999. How they work All Cistercian numerals begin with a vertical line segment, which by itself represents the number 0. Then, glyp...
#Mathematica.2FWolfram_Language
Mathematica/Wolfram Language
ClearAll[CistercianNumberEncodeHelper, CistercianNumberEncode] \[Delta] = 0.25; CistercianNumberEncodeHelper[0] := {} CistercianNumberEncodeHelper[1] := Line[{{0, 1}, {\[Delta], 1}}] CistercianNumberEncodeHelper[2] := Line[{{0, 1 - \[Delta]}, {\[Delta], 1 - \[Delta]}}] CistercianNumberEncodeHelper[3] := Line[{{0, 1}, {...
http://rosettacode.org/wiki/Closest-pair_problem
Closest-pair problem
This page uses content from Wikipedia. The original article was at Closest pair of points problem. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance) Task Provide a function to find the closest two p...
#Elixir
Elixir
defmodule Closest_pair do # brute-force algorithm: def bruteForce([p0,p1|_] = points), do: bf_loop(points, {distance(p0, p1), {p0, p1}})   defp bf_loop([_], acc), do: acc defp bf_loop([h|t], acc), do: bf_loop(t, bf_loop(h, t, acc))   defp bf_loop(_, [], acc), do: acc defp bf_loop(p0, [p1|t], {minD, minP}) d...
http://rosettacode.org/wiki/Closures/Value_capture
Closures/Value capture
Task Create a list of ten functions, in the simplest manner possible   (anonymous functions are encouraged),   such that the function at index   i   (you may choose to start   i   from either   0   or   1),   when run, should return the square of the index,   that is,   i 2. Display the result of runnin...
#Lambdatalk
Lambdatalk
  {def A {A.new {S.map {lambda {:x} {* :x :x}} {S.serie 0 10} }}}   {A.get 3 {A}} // equivalent to A[3] -> 9 {A.get 4 {A}} -> 16  
http://rosettacode.org/wiki/Closures/Value_capture
Closures/Value capture
Task Create a list of ten functions, in the simplest manner possible   (anonymous functions are encouraged),   such that the function at index   i   (you may choose to start   i   from either   0   or   1),   when run, should return the square of the index,   that is,   i 2. Display the result of runnin...
#Latitude
Latitude
functions := 10 times to (Array) map { takes '[i]. proc { (i) * (i). }. }.   functions visit { println: $1 call. }.
http://rosettacode.org/wiki/Circular_primes
Circular primes
Definitions A circular prime is a prime number with the property that the number generated at each intermediate step when cyclically permuting its (base 10) digits will also be prime. For example: 1193 is a circular prime, since 1931, 9311 and 3119 are all also prime. Note that a number which is a cyclic permutation ...
#Phix
Phix
with javascript_semantics function circular(integer p) integer len = length(sprintf("%d",p)), pow = power(10,len-1), p0 = p for i=1 to len-1 do p = pow*remainder(p,10)+floor(p/10) if p<p0 or not is_prime(p) then return false end if end for return true end function...
http://rosettacode.org/wiki/Circles_of_given_radius_through_two_points
Circles of given radius through two points
Given two points on a plane and a radius, usually two circles of given radius can be drawn through the points. Exceptions r==0.0 should be treated as never describing circles (except in the case where the points are coincident). If the points are coincident then an infinite number of circles with the point on thei...
#11l
11l
T Circle Float x, y, r   F String() R ‘Circle(x=#.6, y=#.6, r=#.6)’.format(.x, .y, .r)   F (x, y, r) .x = x .y = y .r = r   T Error String msg F (msg) .msg = msg   F circles_from_p1p2r(p1, p2, r) ‘Following explanation at http://mathforum.org/library/drmath/view/53027.htm...
http://rosettacode.org/wiki/Chinese_zodiac
Chinese zodiac
Traditionally, the Chinese have counted years using two simultaneous cycles, one of length 10 (the "celestial stems") and one of length 12 (the "terrestrial branches"); the combination results in a repeating 60-year pattern. Mapping the branches to twelve traditional animal deities results in the well-known "Chinese zo...
#11l
11l
V animals = [‘Rat’, ‘Ox’, ‘Tiger’, ‘Rabbit’, ‘Dragon’, ‘Snake’, ‘Horse’, ‘Goat’, ‘Monkey’, ‘Rooster’, ‘Dog’, ‘Pig’] V elements = [‘Wood’, ‘Fire’, ‘Earth’, ‘Metal’, ‘Water’]   F getElement(year) R :elements[(year - 4) % 10 I/ 2]   F getAnimal(year) R :animals[(year - 4) % 12]   F getYY(year) I year % 2 == 0 ...
http://rosettacode.org/wiki/Cholesky_decomposition
Cholesky decomposition
Every symmetric, positive definite matrix A can be decomposed into a product of a unique lower triangular matrix L and its transpose: A = L L T {\displaystyle A=LL^{T}} L {\displaystyle L} is called the Cholesky factor of A {\displaystyle A} , and can be interpreted as a generalized square r...
#11l
11l
F cholesky(A) V l = [[0.0] * A.len] * A.len L(i) 0 .< A.len L(j) 0 .. i V s = sum((0 .< j).map(k -> @l[@i][k] * @l[@j][k])) l[i][j] = I (i == j) {sqrt(A[i][i] - s)} E (1.0 / l[j][j] * (A[i][j] - s)) R l   F pprint(m) print(‘[’) L(row) m print(row) print(‘]’)   V m1 = [[25...
http://rosettacode.org/wiki/Collections
Collections
This task has been clarified. Its programming examples are in need of review to ensure that they still fit the requirements of the task. Collections are abstractions to represent sets of values. In statically-typed languages, the values are typically of a common data type. Task Create a collection, and add a fe...
#D
D
int[3] array; array[0] = 5; // array.length = 4; // compile-time error
http://rosettacode.org/wiki/Combinations
Combinations
Task Given non-negative integers   m   and   n,   generate all size   m   combinations   of the integers from   0   (zero)   to   n-1   in sorted order   (each combination is sorted and the entire table is sorted). Example 3   comb   5     is: 0 1 2 0 1 3 0 1 4 0 2 3 0 2 4 0 3 4 1 2 3 1 2 4 1 3 4 2 3 4 ...
#jq
jq
def combination(r): if r > length or r < 0 then empty elif r == length then . else ( [.[0]] + (.[1:]|combination(r-1))), ( .[1:]|combination(r)) end;   # select r integers from the set (0 .. n-1) def combinations(n;r): [range(0;n)] | combination(r);
http://rosettacode.org/wiki/Conditional_structures
Conditional structures
Control Structures These are examples of control structures. You may also be interested in: Conditional structures Exceptions Flow-control structures Loops Task List the conditional structures offered by a programming language. See Wikipedia: conditionals for descriptions. Common conditional structures include ...
#PL.2FM
PL/M
/* IF-THEN-ELSE - THE ELSE STATEMENT; PART IS OPTIONAL */ IF COND THEN STATEMENT1; ELSE STATEMENT2;   /* CAN BE CHAINED - THE ELSE STATEMENTX; PART IS STILL OPTIONAL */ IF COND1 THEN STATEMENT1; ELSE IF CONB2 THEN STATEMENT2; ELSE IF CONB3 THEN STATEMENT3; ELSE STATEMENTX;
http://rosettacode.org/wiki/Comments
Comments
Task Show all ways to include text in a language source file that's completely ignored by the compiler or interpreter. Related tasks   Documentation   Here_document See also   Wikipedia   xkcd (Humor: hand gesture denoting // for "commenting out" people.)
#Xojo
Xojo
  // Comments are denoted by a preceding double slash or or single quote ' and continue to the end of the line. There are no multi-line comment blocks Dim foo As Integer // Comments can also occupy the ends of code lines
http://rosettacode.org/wiki/Comments
Comments
Task Show all ways to include text in a language source file that's completely ignored by the compiler or interpreter. Related tasks   Documentation   Here_document See also   Wikipedia   xkcd (Humor: hand gesture denoting // for "commenting out" people.)
#XPL0
XPL0
Text(0, \comment\ "Hello \not a comment\ World!"); \comment
http://rosettacode.org/wiki/Chernick%27s_Carmichael_numbers
Chernick's Carmichael numbers
In 1939, Jack Chernick proved that, for n ≥ 3 and m ≥ 1: U(n, m) = (6m + 1) * (12m + 1) * Product_{i=1..n-2} (2^i * 9m + 1) is a Carmichael number if all the factors are primes and, for n > 4, m is a multiple of 2^(n-4). Example U(3, m) = (6m + 1) * (12m + 1) * (18m + 1) U(4, m) = U(3, m) * (2^2 * 9m + 1)...
#F.23
F#
  // Generate Chernick's Carmichael numbers. Nigel Galloway: June 1st., 2019 let fMk m k=isPrime(6*m+1) && isPrime(12*m+1) && [1..k-2]|>List.forall(fun n->isPrime(9*(pown 2 n)*m+1)) let fX k=Seq.initInfinite(fun n->(n+1)*(pown 2 (k-4))) |> Seq.filter(fun n->fMk n k ) let cherCar k=let m=Seq.head(fX k) in printfn "m=%d ...
http://rosettacode.org/wiki/Chowla_numbers
Chowla numbers
Chowla numbers are also known as:   Chowla's function   chowla numbers   the chowla function   the chowla number   the chowla sequence The chowla number of   n   is   (as defined by Chowla's function):   the sum of the divisors of   n     excluding unity and   n   where   n   is a positive integer The s...
#AWK
AWK
  # syntax: GAWK -f CHOWLA_NUMBERS.AWK # converted from Go BEGIN { for (i=1; i<=37; i++) { printf("chowla(%2d) = %s\n",i,chowla(i)) } printf("\nCount of primes up to:\n") count = 1 limit = 1e7 sieve(limit) power = 100 for (i=3; i<limit; i+=2) { if (!c[i]) { count++ ...
http://rosettacode.org/wiki/Church_numerals
Church numerals
Task In the Church encoding of natural numbers, the number N is encoded by a function that applies its first argument N times to its second argument. Church zero always returns the identity function, regardless of its first argument. In other words, the first argument is not applied to the second argument at all. C...
#Go
Go
package main   import "fmt"   type any = interface{}   type fn func(any) any   type church func(fn) fn   func zero(f fn) fn { return func(x any) any { return x } }   func (c church) succ() church { return func(f fn) fn { return func(x any) any { return f(c(f)(x)) } } ...
http://rosettacode.org/wiki/Classes
Classes
In object-oriented programming class is a set (a transitive closure) of types bound by the relation of inheritance. It is said that all types derived from some base type T and the type T itself form a class T. The first type T from the class T sometimes is called the root type of the class. A class of types itself, a...
#Component_Pascal
Component Pascal
  MODULE Point; IMPORT Strings; TYPE Instance* = POINTER TO LIMITED RECORD x-, y- : LONGINT; (* Instance variables *) END;   PROCEDURE (self: Instance) Initialize*(x,y: LONGINT), NEW; BEGIN self.x := x; self.y := y END Initialize;   (* constructor *) PROCEDURE New*(x, y: LONGINT): Instance; VAR point: ...
http://rosettacode.org/wiki/Cistercian_numerals
Cistercian numerals
Cistercian numerals were used across Europe by Cistercian monks during the Late Medieval Period as an alternative to Roman numerals. They were used to represent base 10 integers from 0 to 9999. How they work All Cistercian numerals begin with a vertical line segment, which by itself represents the number 0. Then, glyp...
#Nim
Nim
const Size = 15   type Canvas = array[Size, array[Size, char]]     func horizontal(canvas: var Canvas; col1, col2, row: Natural) = for col in col1..col2: canvas[row][col] = 'x'     func vertical(canvas: var Canvas; row1, row2, col: Natural) = for row in row1..row2: canvas[row][col] = 'x'     func diagd(canv...
http://rosettacode.org/wiki/Closest-pair_problem
Closest-pair problem
This page uses content from Wikipedia. The original article was at Closest pair of points problem. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance) Task Provide a function to find the closest two p...
#F.23
F#
  let closest_pairs (xys: Point []) = let n = xys.Length seq { for i in 0..n-2 do for j in i+1..n-1 do yield xys.[i], xys.[j] } |> Seq.minBy (fun (p0, p1) -> (p1 - p0).LengthSquared)  
http://rosettacode.org/wiki/Closures/Value_capture
Closures/Value capture
Task Create a list of ten functions, in the simplest manner possible   (anonymous functions are encouraged),   such that the function at index   i   (you may choose to start   i   from either   0   or   1),   when run, should return the square of the index,   that is,   i 2. Display the result of runnin...
#LFE
LFE
  > (set funcs (list-comp ((<- m (lists:seq 1 10))) (lambda () (math:pow m 2))))  
http://rosettacode.org/wiki/Circular_primes
Circular primes
Definitions A circular prime is a prime number with the property that the number generated at each intermediate step when cyclically permuting its (base 10) digits will also be prime. For example: 1193 is a circular prime, since 1931, 9311 and 3119 are all also prime. Note that a number which is a cyclic permutation ...
#Prolog
Prolog
  ?- use_module(library(primality)).   circular(N) :- member(N, [2, 3, 5, 7]). circular(N) :- limit(15, ( candidate(N), N > 9, circular_prime(N))). circular(r(K)) :- between(6, inf, K), N is (10**K - 1) div 9, prime(N).   candidate(0). candidate(N) :- candidate(M), member...
http://rosettacode.org/wiki/Circles_of_given_radius_through_two_points
Circles of given radius through two points
Given two points on a plane and a radius, usually two circles of given radius can be drawn through the points. Exceptions r==0.0 should be treated as never describing circles (except in the case where the points are coincident). If the points are coincident then an infinite number of circles with the point on thei...
#Action.21
Action!
INCLUDE "H6:REALMATH.ACT"   PROC Circles(CHAR ARRAY sx1,sy1,sx2,sy2,sr) REAL x1,y1,x2,y2,r,x,y,bx,by,pb,cb,xx,yy REAL two,tmp1,tmp2,tmp3   ValR(sx1,x1) ValR(sy1,y1) ValR(sx2,x2) ValR(sy2,y2) ValR(sr,r) IntToReal(2,two)   Print("p1=(") PrintR(x1) Put(32) PrintR(y1) Print(") p2=(") PrintR(x2) Put(32) Pr...
http://rosettacode.org/wiki/Chinese_zodiac
Chinese zodiac
Traditionally, the Chinese have counted years using two simultaneous cycles, one of length 10 (the "celestial stems") and one of length 12 (the "terrestrial branches"); the combination results in a repeating 60-year pattern. Mapping the branches to twelve traditional animal deities results in the well-known "Chinese zo...
#360_Assembly
360 Assembly
* Chinese zodiac 10/03/2019 CHINEZOD CSECT USING CHINEZOD,R13 base register B 72(R15) skip savearea DC 17F'0' savearea SAVE (14,12) save previous context ST R13,4(R15) link backward ST...
http://rosettacode.org/wiki/Cholesky_decomposition
Cholesky decomposition
Every symmetric, positive definite matrix A can be decomposed into a product of a unique lower triangular matrix L and its transpose: A = L L T {\displaystyle A=LL^{T}} L {\displaystyle L} is called the Cholesky factor of A {\displaystyle A} , and can be interpreted as a generalized square r...
#Ada
Ada
with Ada.Numerics.Generic_Real_Arrays; generic with package Matrix is new Ada.Numerics.Generic_Real_Arrays (<>); package Decomposition is   -- decompose a square matrix A by A = L * Transpose (L) procedure Decompose (A : Matrix.Real_Matrix; L : out Matrix.Real_Matrix);   end Decomposition;
http://rosettacode.org/wiki/Collections
Collections
This task has been clarified. Its programming examples are in need of review to ensure that they still fit the requirements of the task. Collections are abstractions to represent sets of values. In statically-typed languages, the values are typically of a common data type. Task Create a collection, and add a fe...
#Delphi
Delphi
  // Creates and initializes a new integer Array var // Dynamics arrays can be initialized, if it's global variable in declaration scope intArray: TArray<Integer> = [1, 2, 3, 4, 5]; intArray2: array of Integer = [1, 2, 3, 4, 5];   //Cann't initialize statics arrays in declaration scope intArray3: a...
http://rosettacode.org/wiki/Combinations
Combinations
Task Given non-negative integers   m   and   n,   generate all size   m   combinations   of the integers from   0   (zero)   to   n-1   in sorted order   (each combination is sorted and the entire table is sorted). Example 3   comb   5     is: 0 1 2 0 1 3 0 1 4 0 2 3 0 2 4 0 3 4 1 2 3 1 2 4 1 3 4 2 3 4 ...
#Julia
Julia
using Combinatorics n = 4 m = 3 for i in combinations(0:n,m) println(i') end
http://rosettacode.org/wiki/Conditional_structures
Conditional structures
Control Structures These are examples of control structures. You may also be interested in: Conditional structures Exceptions Flow-control structures Loops Task List the conditional structures offered by a programming language. See Wikipedia: conditionals for descriptions. Common conditional structures include ...
#Pop11
Pop11
if condition then  ;;; Action endif;
http://rosettacode.org/wiki/Comments
Comments
Task Show all ways to include text in a language source file that's completely ignored by the compiler or interpreter. Related tasks   Documentation   Here_document See also   Wikipedia   xkcd (Humor: hand gesture denoting // for "commenting out" people.)
#XQuery
XQuery
(: This is a XQuery comment :)
http://rosettacode.org/wiki/Comments
Comments
Task Show all ways to include text in a language source file that's completely ignored by the compiler or interpreter. Related tasks   Documentation   Here_document See also   Wikipedia   xkcd (Humor: hand gesture denoting // for "commenting out" people.)
#XSLT
XSLT
<!-- Comment syntax is borrowed from XML and HTML. -->
http://rosettacode.org/wiki/Chinese_remainder_theorem
Chinese remainder theorem
Suppose   n 1 {\displaystyle n_{1}} ,   n 2 {\displaystyle n_{2}} ,   … {\displaystyle \ldots } ,   n k {\displaystyle n_{k}}   are positive integers that are pairwise co-prime.   Then, for any given sequence of integers   a 1 {\displaystyle a_{1}} ,   a 2 ...
#11l
11l
F mul_inv(=a, =b) V b0 = b V x0 = 0 V x1 = 1 I b == 1 R 1 L a > 1 V q = a I/ b (a, b) = (b, a % b) (x0, x1) = (x1 - q * x0, x0) I x1 < 0 x1 += b0 R x1   F chinese_remainder(n, a) V sum = 0 V prod = product(n) L(n_i, a_i) zip(n, a) V p = prod I/ n_i ...
http://rosettacode.org/wiki/Chernick%27s_Carmichael_numbers
Chernick's Carmichael numbers
In 1939, Jack Chernick proved that, for n ≥ 3 and m ≥ 1: U(n, m) = (6m + 1) * (12m + 1) * Product_{i=1..n-2} (2^i * 9m + 1) is a Carmichael number if all the factors are primes and, for n > 4, m is a multiple of 2^(n-4). Example U(3, m) = (6m + 1) * (12m + 1) * (18m + 1) U(4, m) = U(3, m) * (2^2 * 9m + 1)...
#FreeBASIC
FreeBASIC
#include "isprime.bas"   Function PrimalityPretest(k As Integer) As Boolean Dim As Integer ppp(1 To 8) = {3,5,7,11,13,17,19,23} For i As Integer = 1 To Ubound(ppp) If k Mod ppp(i) = 0 Then Return (k <= 23) Next i Return True End Function   Function isChernick(n As Integer, m As Integer) As Boole...
http://rosettacode.org/wiki/Chowla_numbers
Chowla numbers
Chowla numbers are also known as:   Chowla's function   chowla numbers   the chowla function   the chowla number   the chowla sequence The chowla number of   n   is   (as defined by Chowla's function):   the sum of the divisors of   n     excluding unity and   n   where   n   is a positive integer The s...
#C
C
#include <stdio.h>   unsigned chowla(const unsigned n) { unsigned sum = 0; for (unsigned i = 2, j; i * i <= n; i ++) if (n % i == 0) sum += i + (i == (j = n / i) ? 0 : j); return sum; }   int main(int argc, char const *argv[]) { unsigned a; for (unsigned n = 1; n < 38; n ++) printf("chowla(%u) = %u\n", n, cho...
http://rosettacode.org/wiki/Church_numerals
Church numerals
Task In the Church encoding of natural numbers, the number N is encoded by a function that applies its first argument N times to its second argument. Church zero always returns the identity function, regardless of its first argument. In other words, the first argument is not applied to the second argument at all. C...
#Groovy
Groovy
class ChurchNumerals { static void main(args) {   def zero = { f -> { a -> a } } def succ = { n -> { f -> { a -> f(n(f)(a)) } } } def add = { n -> { k -> { n(succ)(k) } } } def mult = { f -> { g -> { a -> f(g(a)) } } } def pow = { f -> { g -> g(f) } }   def toChurchNu...
http://rosettacode.org/wiki/Classes
Classes
In object-oriented programming class is a set (a transitive closure) of types bound by the relation of inheritance. It is said that all types derived from some base type T and the type T itself form a class T. The first type T from the class T sometimes is called the root type of the class. A class of types itself, a...
#Crystal
Crystal
class MyClass   def initialize @instance_var = 0 end   def add_1 @instance_var += 1 end   end   my_class = MyClass.new  
http://rosettacode.org/wiki/Cistercian_numerals
Cistercian numerals
Cistercian numerals were used across Europe by Cistercian monks during the Late Medieval Period as an alternative to Roman numerals. They were used to represent base 10 integers from 0 to 9999. How they work All Cistercian numerals begin with a vertical line segment, which by itself represents the number 0. Then, glyp...
#Perl
Perl
#!/usr/bin/perl   use strict; # https://rosettacode.org/wiki/Cistercian_numerals use warnings;   my @pts = ('', qw( 01 23 03 12 012 13 013 132 0132) ); my @dots = qw( 4-0 8-0 4-4 8-4 );   my @images = map { sprintf("%-9s\n", "$_:") . draw($_) } 0, 1, 20, 300, 4000, 5555, 6789, 1133; for ( 1 .. 13 ) { s/(.+)\n/ pr...
http://rosettacode.org/wiki/Closest-pair_problem
Closest-pair problem
This page uses content from Wikipedia. The original article was at Closest pair of points problem. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance) Task Provide a function to find the closest two p...
#Fantom
Fantom
  class Point { Float x Float y   // create a random point new make (Float x := Float.random * 10, Float y := Float.random * 10) { this.x = x this.y = y }   Float distance (Point p) { ((x-p.x)*(x-p.x) + (y-p.y)*(y-p.y)).sqrt }   override Str toStr () { "($x, $y)" } }   class Main { //...
http://rosettacode.org/wiki/Closures/Value_capture
Closures/Value capture
Task Create a list of ten functions, in the simplest manner possible   (anonymous functions are encouraged),   such that the function at index   i   (you may choose to start   i   from either   0   or   1),   when run, should return the square of the index,   that is,   i 2. Display the result of runnin...
#Lingo
Lingo
-- parent script "CallFunction"   property _code   -- if the function is supposed to return something, the code must contain a line that starts with "res=" on new (me, code) me._code = code return me end   on call (me) ---------------------------------------- -- If custom arguments were passed, evaluate them ...
http://rosettacode.org/wiki/Closures/Value_capture
Closures/Value capture
Task Create a list of ten functions, in the simplest manner possible   (anonymous functions are encouraged),   such that the function at index   i   (you may choose to start   i   from either   0   or   1),   when run, should return the square of the index,   that is,   i 2. Display the result of runnin...
#Logtalk
Logtalk
  :- object(value_capture).   :- public(show/0). show :- integer::sequence(1, 10, List), meta::map(create_closure, List, Closures), meta::map(call_closure, List, Closures).   create_closure(Index, [Double]>>(Double is Index*Index)).   call_closure(Index, Closure) :- call(...
http://rosettacode.org/wiki/Circular_primes
Circular primes
Definitions A circular prime is a prime number with the property that the number generated at each intermediate step when cyclically permuting its (base 10) digits will also be prime. For example: 1193 is a circular prime, since 1931, 9311 and 3119 are all also prime. Note that a number which is a cyclic permutation ...
#Python
Python
  import random   def is_Prime(n): """ Miller-Rabin primality test.   A return value of False means n is certainly not prime. A return value of True means n is very likely a prime. """ if n!=int(n): return False n=int(n) #Miller-Rabin test for prime if n==0 or n==1 or n==4 or...
http://rosettacode.org/wiki/Circles_of_given_radius_through_two_points
Circles of given radius through two points
Given two points on a plane and a radius, usually two circles of given radius can be drawn through the points. Exceptions r==0.0 should be treated as never describing circles (except in the case where the points are coincident). If the points are coincident then an infinite number of circles with the point on thei...
#ALGOL_68
ALGOL 68
# represents a point # MODE POINT = STRUCT( REAL x, REAL y ); # returns TRUE if p1 is the same point as p2, FALSE otherwise # OP = = ( POINT p1, POINT p2 )BOOL: x OF p1 = x OF p2 AND y OF p1 = y OF p2;   # represents a circle with centre c and radius r ...
http://rosettacode.org/wiki/Chinese_zodiac
Chinese zodiac
Traditionally, the Chinese have counted years using two simultaneous cycles, one of length 10 (the "celestial stems") and one of length 12 (the "terrestrial branches"); the combination results in a repeating 60-year pattern. Mapping the branches to twelve traditional animal deities results in the well-known "Chinese zo...
#Action.21
Action!
DEFINE PTR="CARD"   PTR ARRAY animals(12),elements(5),stems(10),branches(12),yinYangs(2)   PROC Init() animals(0)="Rat" animals(1)="Ox" animals(2)="Tiger" animals(3)="Rabbit" animals(4)="Dragon" animals(5)="Snake" animals(6)="Horse" animals(7)="Goat" animals(8)="Monkey" animals(9)="Rooster" animals(10)...
http://rosettacode.org/wiki/Chinese_zodiac
Chinese zodiac
Traditionally, the Chinese have counted years using two simultaneous cycles, one of length 10 (the "celestial stems") and one of length 12 (the "terrestrial branches"); the combination results in a repeating 60-year pattern. Mapping the branches to twelve traditional animal deities results in the well-known "Chinese zo...
#Ada
Ada
  with Ada.Text_IO; use Ada.Text_IO; with Ada.Strings.Unbounded; use Ada.Strings.Unbounded; procedure Main is   type Element_Index is mod 5; type Animal_Index is mod 12; type Stem_Index is mod 10;   type Animal_Array is array(Animal_Index range <>) of Unbounded_String; type Element_Array is array(Elemen...
http://rosettacode.org/wiki/Cholesky_decomposition
Cholesky decomposition
Every symmetric, positive definite matrix A can be decomposed into a product of a unique lower triangular matrix L and its transpose: A = L L T {\displaystyle A=LL^{T}} L {\displaystyle L} is called the Cholesky factor of A {\displaystyle A} , and can be interpreted as a generalized square r...
#ALGOL_68
ALGOL 68
#!/usr/local/bin/a68g --script #   MODE FIELD=LONG REAL; PROC (FIELD)FIELD field sqrt = long sqrt; INT field prec = 5; FORMAT field fmt = $g(-(2+1+field prec),field prec)$;   MODE MAT = [0,0]FIELD;   PROC cholesky = (MAT a) MAT:( [UPB a, 2 UPB a]FIELD l;   FOR i FROM LWB a TO UPB a DO FOR j FROM 2 LWB a...
http://rosettacode.org/wiki/Collections
Collections
This task has been clarified. Its programming examples are in need of review to ensure that they still fit the requirements of the task. Collections are abstractions to represent sets of values. In statically-typed languages, the values are typically of a common data type. Task Create a collection, and add a fe...
#E
E
? def constList := [1,2,3,4,5] # value: [1, 2, 3, 4, 5]   ? constList.with(6) # value: [1, 2, 3, 4, 5, 6]   ? def flexList := constList.diverge() # value: [1, 2, 3, 4, 5].diverge()   ? flexList.push(6) ? flexList # value: [1, 2, 3, 4, 5, 6].diverge()   ? constList # value: [1, 2, 3, 4, 5]   ? def constMap := [1 => 2, 3...
http://rosettacode.org/wiki/Combinations
Combinations
Task Given non-negative integers   m   and   n,   generate all size   m   combinations   of the integers from   0   (zero)   to   n-1   in sorted order   (each combination is sorted and the entire table is sorted). Example 3   comb   5     is: 0 1 2 0 1 3 0 1 4 0 2 3 0 2 4 0 3 4 1 2 3 1 2 4 1 3 4 2 3 4 ...
#K
K
comb:{[n;k] f:{:[k=#x; :,x; :,/_f' x,'(1+*|x) _ !n]}  :,/f' !n }
http://rosettacode.org/wiki/Conditional_structures
Conditional structures
Control Structures These are examples of control structures. You may also be interested in: Conditional structures Exceptions Flow-control structures Loops Task List the conditional structures offered by a programming language. See Wikipedia: conditionals for descriptions. Common conditional structures include ...
#PostScript
PostScript
9 10 lt {(9 is less than 10) show} if
http://rosettacode.org/wiki/Comments
Comments
Task Show all ways to include text in a language source file that's completely ignored by the compiler or interpreter. Related tasks   Documentation   Here_document See also   Wikipedia   xkcd (Humor: hand gesture denoting // for "commenting out" people.)
#XUL
XUL
<!-- Comment syntax is borrowed from XML and HTML. -->
http://rosettacode.org/wiki/Comments
Comments
Task Show all ways to include text in a language source file that's completely ignored by the compiler or interpreter. Related tasks   Documentation   Here_document See also   Wikipedia   xkcd (Humor: hand gesture denoting // for "commenting out" people.)
#Yacas
Yacas
// This is a single line comment /* This comment spans multiple lines */
http://rosettacode.org/wiki/Chinese_remainder_theorem
Chinese remainder theorem
Suppose   n 1 {\displaystyle n_{1}} ,   n 2 {\displaystyle n_{2}} ,   … {\displaystyle \ldots } ,   n k {\displaystyle n_{k}}   are positive integers that are pairwise co-prime.   Then, for any given sequence of integers   a 1 {\displaystyle a_{1}} ,   a 2 ...
#360_Assembly
360 Assembly
* Chinese remainder theorem 06/09/2015 CHINESE CSECT USING CHINESE,R12 base addr LR R12,R15 BEGIN LA R9,1 m=1 LA R6,1 j=1 LOOPJ C R6,NN do j=1 to nn BH ELOOPJ LR R1,R6 j ...
http://rosettacode.org/wiki/Chinese_remainder_theorem
Chinese remainder theorem
Suppose   n 1 {\displaystyle n_{1}} ,   n 2 {\displaystyle n_{2}} ,   … {\displaystyle \ldots } ,   n k {\displaystyle n_{k}}   are positive integers that are pairwise co-prime.   Then, for any given sequence of integers   a 1 {\displaystyle a_{1}} ,   a 2 ...
#Action.21
Action!
INT FUNC MulInv(INT a,b) INT b0,x0,x1,q,tmp   IF b=1 THEN RETURN (1) FI   b0=b x0=0 x1=1 WHILE a>1 DO q=a/b   tmp=b b=a MOD b a=tmp   tmp=x0 x0=x1-q*x0 x1=tmp OD IF x1<0 THEN x1==+b0 FI RETURN (x1)   INT FUNC ChineseRemainder(BYTE ARRAY n,a BYTE len) INT prod,sum,p,m ...
http://rosettacode.org/wiki/Chernick%27s_Carmichael_numbers
Chernick's Carmichael numbers
In 1939, Jack Chernick proved that, for n ≥ 3 and m ≥ 1: U(n, m) = (6m + 1) * (12m + 1) * Product_{i=1..n-2} (2^i * 9m + 1) is a Carmichael number if all the factors are primes and, for n > 4, m is a multiple of 2^(n-4). Example U(3, m) = (6m + 1) * (12m + 1) * (18m + 1) U(4, m) = U(3, m) * (2^2 * 9m + 1)...
#Go
Go
package main   import ( "fmt" "math/big" )   var ( zero = new(big.Int) prod = new(big.Int) fact = new(big.Int) )   func ccFactors(n, m uint64) (*big.Int, bool) { prod.SetUint64(6*m + 1) if !prod.ProbablyPrime(0) { return zero, false } fact.SetUint64(12*m + 1) if !fact.Pro...
http://rosettacode.org/wiki/Chowla_numbers
Chowla numbers
Chowla numbers are also known as:   Chowla's function   chowla numbers   the chowla function   the chowla number   the chowla sequence The chowla number of   n   is   (as defined by Chowla's function):   the sum of the divisors of   n     excluding unity and   n   where   n   is a positive integer The s...
#C.23
C#
using System;   namespace chowla_cs { class Program { static int chowla(int n) { int sum = 0; for (int i = 2, j; i * i <= n; i++) if (n % i == 0) sum += i + (i == (j = n / i) ? 0 : j); return sum; }   static bool[] sieve(int lim...
http://rosettacode.org/wiki/Church_numerals
Church numerals
Task In the Church encoding of natural numbers, the number N is encoded by a function that applies its first argument N times to its second argument. Church zero always returns the identity function, regardless of its first argument. In other words, the first argument is not applied to the second argument at all. C...
#Haskell
Haskell
import Unsafe.Coerce ( unsafeCoerce )   type Church a = (a -> a) -> a -> a   churchZero :: Church a churchZero = const id   churchOne :: Church a churchOne = id   succChurch :: Church a -> Church a succChurch = (<*>) (.) -- add one recursion, or \ ch f -> f . ch f   addChurch :: Church a -> Church a -> Church a addChu...
http://rosettacode.org/wiki/Classes
Classes
In object-oriented programming class is a set (a transitive closure) of types bound by the relation of inheritance. It is said that all types derived from some base type T and the type T itself form a class T. The first type T from the class T sometimes is called the root type of the class. A class of types itself, a...
#D
D
import std.stdio;   class MyClass { //constructor (not necessary if empty) this() {}   void someMethod() { variable = 1; }   // getter method @property int variable() const { return variable_; }   // setter method @property int variable(int newVariable) { retu...
http://rosettacode.org/wiki/Cistercian_numerals
Cistercian numerals
Cistercian numerals were used across Europe by Cistercian monks during the Late Medieval Period as an alternative to Roman numerals. They were used to represent base 10 integers from 0 to 9999. How they work All Cistercian numerals begin with a vertical line segment, which by itself represents the number 0. Then, glyp...
#Phix
Phix
-- -- Define each digit as {up-down multiplier, left-right multiplier, char}, -- that is starting each drawing from line 1 or 7, column 3, -- and with `/` and `\` being flipped below when necessary. -- with javascript_semantics constant ds = {{{0,0,'+'},{0,1,'-'},{0,2,'-'}}, -- 1 ...
http://rosettacode.org/wiki/Closest-pair_problem
Closest-pair problem
This page uses content from Wikipedia. The original article was at Closest pair of points problem. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance) Task Provide a function to find the closest two p...
#Fortran
Fortran
  Dim As Integer i, j Dim As Double minDist = 1^30 Dim As Double x(9), y(9), dist, mini, minj   Data 0.654682, 0.925557 Data 0.409382, 0.619391 Data 0.891663, 0.888594 Data 0.716629, 0.996200 Data 0.477721, 0.946355 Data 0.925092, 0.818220 Data 0.624291, 0.142924 Data 0.211332, 0.221507 Data 0.293786, 0.691701...
http://rosettacode.org/wiki/Closures/Value_capture
Closures/Value capture
Task Create a list of ten functions, in the simplest manner possible   (anonymous functions are encouraged),   such that the function at index   i   (you may choose to start   i   from either   0   or   1),   when run, should return the square of the index,   that is,   i 2. Display the result of runnin...
#Lua
Lua
  funcs={} for i=1,10 do table.insert(funcs, function() return i*i end) end funcs[2]() funcs[3]()  
http://rosettacode.org/wiki/Circular_primes
Circular primes
Definitions A circular prime is a prime number with the property that the number generated at each intermediate step when cyclically permuting its (base 10) digits will also be prime. For example: 1193 is a circular prime, since 1931, 9311 and 3119 are all also prime. Note that a number which is a cyclic permutation ...
#Raku
Raku
sub isCircular(\n) { return False unless n.is-prime; my @circular = n.comb; return False if @circular.min < @circular[0]; for 1 ..^ @circular -> $i { return False unless .is-prime and $_ >= n given @circular.rotate($i).join; } True }   say "The first 19 circular primes are:"; say ((2..*).hyper.g...
http://rosettacode.org/wiki/Circles_of_given_radius_through_two_points
Circles of given radius through two points
Given two points on a plane and a radius, usually two circles of given radius can be drawn through the points. Exceptions r==0.0 should be treated as never describing circles (except in the case where the points are coincident). If the points are coincident then an infinite number of circles with the point on thei...
#AutoHotkey
AutoHotkey
CircleCenter(x1, y1, x2, y2, r){ d := sqrt((x2-x1)**2 + (y2-y1)**2) x3 := (x1+x2)/2 , y3 := (y1+y2)/2 cx1 := x3 + sqrt(r**2-(d/2)**2)*(y1-y2)/d , cy1:= y3 + sqrt(r**2-(d/2)**2)*(x2-x1)/d cx2 := x3 - sqrt(r**2-(d/2)**2)*(y1-y2)/d , cy2:= y3 - sqrt(r**2-(d/2)**2)*(x2-x1)/d if (d = 0) return "No circles can be dr...
http://rosettacode.org/wiki/Chinese_zodiac
Chinese zodiac
Traditionally, the Chinese have counted years using two simultaneous cycles, one of length 10 (the "celestial stems") and one of length 12 (the "terrestrial branches"); the combination results in a repeating 60-year pattern. Mapping the branches to twelve traditional animal deities results in the well-known "Chinese zo...
#ALGOL_68
ALGOL 68
BEGIN # Chinese Zodiac # # returns s right-padded with blanks to w characters, or s if s is already at least w characters long # PRIO PAD = 1; OP PAD = ( STRING s, INT w )STRING: BEGIN STRING result := s; WHILE ( ( UPB result + 1 ) - LWB s ) < w DO result +:= " " OD; ...
http://rosettacode.org/wiki/Cholesky_decomposition
Cholesky decomposition
Every symmetric, positive definite matrix A can be decomposed into a product of a unique lower triangular matrix L and its transpose: A = L L T {\displaystyle A=LL^{T}} L {\displaystyle L} is called the Cholesky factor of A {\displaystyle A} , and can be interpreted as a generalized square r...
#AutoHotkey
AutoHotkey
Cholesky_Decomposition(A){ L := [], n := A.Count() L[1,1] := Sqrt(A[1,1]) loop % n { k := A_Index loop % n-1 { i := A_Index+1   Sigma := 0, j := 0 while (++j <= k-1) Sigma += L[i, j] * L[k, j] L[i, k] := (A[i, k] - Sigma) / L[k,...
http://rosettacode.org/wiki/Cheryl%27s_birthday
Cheryl's birthday
Albert and Bernard just became friends with Cheryl, and they want to know when her birthday is. Cheryl gave them a list of ten possible dates: May 15, May 16, May 19 June 17, June 18 July 14, July 16 August 14, August 15, August 17 Cheryl then tells Albert the   month   of birth, ...
#11l
11l
T Date String month Int day F (month, day) .month = month .day = day   V dates = [Date(‘May’, 15), Date(‘May’, 16), Date(‘May’, 19), Date(‘June’, 17), Date(‘June’, 18), Date(‘July’, 14), Date(‘July’, 16), Date(‘August’, 14), Date(‘August’, 15), Date(‘August’, 17)]   DefaultDict[Int, Set[...