task_url
stringlengths
30
116
task_name
stringlengths
2
86
task_description
stringlengths
0
14.4k
language_url
stringlengths
2
53
language_name
stringlengths
1
52
code
stringlengths
0
61.9k
http://rosettacode.org/wiki/Verify_distribution_uniformity/Naive
Verify distribution uniformity/Naive
This task is an adjunct to Seven-sided dice from five-sided dice. Task Create a function to check that the random integers returned from a small-integer generator function have uniform distribution. The function should take as arguments: The function (or object) producing random integers. The number of times ...
#zkl
zkl
fcn rtest(N){ dist:=L(0,0,0,0,0,0,0,0,0,0); do(N){n:=(0).random(10); dist[n]=dist[n]+1} sum:=dist.sum(); dist=dist.apply('wrap(n){n.toFloat()/sum*100}); if (dist.filter((10.0).closeTo.fp1(0.1)).len() == 10) { "Good enough at %,d: %s".fmt(N,dist).println(); return(True); } False }   n:=10; while...
http://rosettacode.org/wiki/Variable_declaration_reset
Variable declaration reset
A decidely non-challenging task to highlight a potential difference between programming languages. Using a straightforward longhand loop as in the JavaScript and Phix examples below, show the locations of elements which are identical to the immediately preceding element in {1,2,2,3,4,4,5}. The (non-blank) results may ...
#J
J
1+I.(}:=}.) 1 2 2 3 4 4 5 2 5
http://rosettacode.org/wiki/Variable_declaration_reset
Variable declaration reset
A decidely non-challenging task to highlight a potential difference between programming languages. Using a straightforward longhand loop as in the JavaScript and Phix examples below, show the locations of elements which are identical to the immediately preceding element in {1,2,2,3,4,4,5}. The (non-blank) results may ...
#Java
Java
public class VariableDeclarationReset { public static void main(String[] args) { int[] s = {1, 2, 2, 3, 4, 4, 5};   // There is no output as 'prev' is created anew each time // around the loop and set to zero. for (int i = 0; i < s.length; ++i) { int curr = s[i]; ...
http://rosettacode.org/wiki/Variable_declaration_reset
Variable declaration reset
A decidely non-challenging task to highlight a potential difference between programming languages. Using a straightforward longhand loop as in the JavaScript and Phix examples below, show the locations of elements which are identical to the immediately preceding element in {1,2,2,3,4,4,5}. The (non-blank) results may ...
#JavaScript
JavaScript
<!DOCTYPE html> <html lang="en" > <head> <meta charset="utf-8"/> <meta name="viewport" content="width=device-width, initial-scale=1"/> <title>variable declaration reset</title> </head> <body> <script> "use strict"; let s = [1, 2, 2, 3, 4, 4, 5]; for (let i=0; i<7; i+=1) { let curr = s[i], prev; if (i...
http://rosettacode.org/wiki/Van_der_Corput_sequence
Van der Corput sequence
When counting integers in binary, if you put a (binary) point to the righEasyLangt of the count then the column immediately to the left denotes a digit with a multiplier of 2 0 {\displaystyle 2^{0}} ; the digit in the next column to the left has a multiplier of 2 1 {\displaystyle 2^{1}} ; and so o...
#360_Assembly
360 Assembly
* Van der Corput sequence 31/01/2017 VDCS CSECT USING VDCS,R13 base register B 72(R15) skip savearea DC 17F'0' savearea STM R14,R12,12(R13) prolog ST R13,4(R15) " <- ST R15,8(R13) ...
http://rosettacode.org/wiki/Van_der_Corput_sequence
Van der Corput sequence
When counting integers in binary, if you put a (binary) point to the righEasyLangt of the count then the column immediately to the left denotes a digit with a multiplier of 2 0 {\displaystyle 2^{0}} ; the digit in the next column to the left has a multiplier of 2 1 {\displaystyle 2^{1}} ; and so o...
#Action.21
Action!
INCLUDE "D2:REAL.ACT" ;from the Action! Tool Kit   PROC Generate(INT value,base REAL POINTER res) REAL denom,rbase,r1,r2   IntToReal(0,res) IntToReal(1,denom) IntToReal(base,rbase) WHILE value#0 DO RealMult(denom,rbase,r1) RealAssign(r1,denom) IntToReal(value MOD base,r1) RealDiv(r1,denom,r2...
http://rosettacode.org/wiki/Variables
Variables
Task Demonstrate a language's methods of:   variable declaration   initialization   assignment   datatypes   scope   referencing,     and   other variable related facilities
#8086_Assembly
8086 Assembly
.data MyVar word 0FFFFh ;the leading zero is just to help the assembler tell that this is a number, it's not actually part of the variable.   .code   mov ax, word ptr [ds:MyVar]
http://rosettacode.org/wiki/Variables
Variables
Task Demonstrate a language's methods of:   variable declaration   initialization   assignment   datatypes   scope   referencing,     and   other variable related facilities
#8th
8th
  \ declare a variable which is initialized to the number '0' var x   \ declare a variable which is initialized to a string "cat" "cat" var, y   \ Get the value in x, add 20 and store it: x @ 20 n:+ x !   \ Change the cat to a dog: "dog" y !  
http://rosettacode.org/wiki/Van_Eck_sequence
Van Eck sequence
The sequence is generated by following this pseudo-code: A: The first term is zero. Repeatedly apply: If the last term is *new* to the sequence so far then: B: The next term is zero. Otherwise: C: The next term is how far back this last term occured previously. Example Using ...
#Ada
Ada
with Ada.Text_IO;   procedure Van_Eck_Sequence is   Sequence : array (Natural range 1 .. 1_000) of Natural;   procedure Calculate_Sequence is begin Sequence (Sequence'First) := 0; for Index in Sequence'First .. Sequence'Last - 1 loop Sequence (Index + 1) := 0; for I in reverse Seq...
http://rosettacode.org/wiki/Vampire_number
Vampire number
A vampire number is a natural decimal number with an even number of digits,   that can be factored into two integers. These two factors are called the   fangs,   and must have the following properties:   they each contain half the number of the decimal digits of the original number   together they consist of exactl...
#Bracmat
Bracmat
( ( vampire = N len R fangsList .  !arg:@(?N:? [?len) & 1/2*!len:~/:?len & ( R = len numpart left right allowed fangs rdigits , tried digit untried head tail found .  !arg:(?len.?left.?numpart.?allowed) & :?found & (  !len:>0 ...
http://rosettacode.org/wiki/Vampire_number
Vampire number
A vampire number is a natural decimal number with an even number of digits,   that can be factored into two integers. These two factors are called the   fangs,   and must have the following properties:   they each contain half the number of the decimal digits of the original number   together they consist of exactl...
#C
C
#include <stdio.h> #include <stdlib.h> #include <stdint.h> #include <math.h>   typedef uint64_t xint; typedef unsigned long long ull;   xint tens[20];   inline xint max(xint a, xint b) { return a > b ? a : b; } inline xint min(xint a, xint b) { return a < b ? a : b; } inline int ndigits(xint x) { int n = 0; while (x)...
http://rosettacode.org/wiki/Variable-length_quantity
Variable-length quantity
Implement some operations on variable-length quantities, at least including conversions from a normal number in the language to the binary representation of the variable-length quantity for that number, and vice versa. Any variants are acceptable. Task With above operations, convert these two numbers 0x200000 (209...
#PARI.2FGP
PARI/GP
hex(s)=my(a=10,b=11,c=12,d=13,e=14,f=15);subst(Pol(eval(Vec(s))),'x,16); n1=hex("200000");n2=hex("1fffff"); v1=digits(n1,256) v2=digits(n2,256) subst(Pol(v1),'x,256)==n1 subst(Pol(v2),'x,256)==n2
http://rosettacode.org/wiki/Variable-length_quantity
Variable-length quantity
Implement some operations on variable-length quantities, at least including conversions from a normal number in the language to the binary representation of the variable-length quantity for that number, and vice versa. Any variants are acceptable. Task With above operations, convert these two numbers 0x200000 (209...
#Perl
Perl
  use warnings; use strict;   for my $testcase ( 0, 0xa, 123, 254, 255, 256, 257, 65534, 65535, 65536, 65537, 0x1fffff, 0x200000 ) { my @vlq = vlq_encode($testcase); printf "%8s %12s %8s\n", $testcase, ( join ':', @vlq ), vlq_decode(@vlq); }   sub vlq_encode { my @vlq; my $binary...
http://rosettacode.org/wiki/Variadic_function
Variadic function
Task Create a function which takes in a variable number of arguments and prints each one on its own line. Also show, if possible in your language, how to call the function on a list of arguments constructed at runtime. Functions of this type are also known as Variadic Functions. Related task   Call a function...
#D
D
import std.stdio, std.algorithm;   void printAll(TyArgs...)(TyArgs args) { foreach (el; args) el.writeln; }   // Typesafe variadic function for dynamic array void showSum1(int[] items...) { items.sum.writeln; }   // Typesafe variadic function for fixed size array void showSum2(int[4] items...) { ite...
http://rosettacode.org/wiki/Variadic_function
Variadic function
Task Create a function which takes in a variable number of arguments and prints each one on its own line. Also show, if possible in your language, how to call the function on a list of arguments constructed at runtime. Functions of this type are also known as Variadic Functions. Related task   Call a function...
#Delphi
Delphi
func printAll(args...) { for i in args { print(i) } }   printAll("test", "rosetta code", 123, 5.6)
http://rosettacode.org/wiki/Variable_size/Get
Variable size/Get
Demonstrate how to get the size of a variable. See also: Host introspection
#Factor
Factor
USING: layouts memory prettyprint ;   ! Show size in bytes { 1 2 3 } size .  ! 48 1231298302914891021239102 size .  ! 48   ! Doesn't work on fixnums and other immediate objects 10 size .  ! 0   ! Show number of bits in a fixnum fixnum-bits .  ! 60
http://rosettacode.org/wiki/Variable_size/Get
Variable size/Get
Demonstrate how to get the size of a variable. See also: Host introspection
#Forth
Forth
: .CELLSIZE ( -- ) CR 1 CELLS . ." Bytes" ; VARIABLE X ( creates a variable 1 cell wide)
http://rosettacode.org/wiki/Variable_size/Get
Variable size/Get
Demonstrate how to get the size of a variable. See also: Host introspection
#Fortran
Fortran
INTEGER, PARAMETER :: i8 = SELECTED_INT_KIND(2) INTEGER, PARAMETER :: i16 = SELECTED_INT_KIND(4) INTEGER, PARAMETER :: i32 = SELECTED_INT_KIND(8) INTEGER, PARAMETER :: i64 = SELECTED_INT_KIND(16) INTEGER(i8) :: onebyte = 0 INTEGER(i16) :: twobytes = 0 INTEGER(i32) :: fourbytes = 0 INTEGER(i64) :: eightbytes = 0   WRI...
http://rosettacode.org/wiki/Vector
Vector
Task Implement a Vector class (or a set of functions) that models a Physical Vector. The four basic operations and a pretty print function should be implemented. The Vector may be initialized in any reasonable way. Start and end points, and direction Angular coefficient and value (length) The four operations to...
#jq
jq
def polar(r; angle): [ r*(angle|cos), r*(angle|sin) ];   # If your jq allows multi-arity functions, you may wish to uncomment the following line: # def polar(r): [r, 0];   def polar2vector: polar(.[0]; .[1]);   def vector(x; y): if (x|type) == "number" and (y|type) == "number" then [x,y] else error("TypeError") ...
http://rosettacode.org/wiki/Vector
Vector
Task Implement a Vector class (or a set of functions) that models a Physical Vector. The four basic operations and a pretty print function should be implemented. The Vector may be initialized in any reasonable way. Start and end points, and direction Angular coefficient and value (length) The four operations to...
#Julia
Julia
module SpatialVectors   export SpatialVector   struct SpatialVector{N, T} coord::NTuple{N, T} end   SpatialVector(s::NTuple{N,T}, e::NTuple{N,T}) where {N,T} = SpatialVector{N, T}(e .- s) function SpatialVector(∠::T, val::T) where T θ = atan(∠) x = val * cos(θ) y = val * sin(θ) return SpatialVec...
http://rosettacode.org/wiki/Verify_distribution_uniformity/Chi-squared_test
Verify distribution uniformity/Chi-squared test
Task Write a function to verify that a given distribution of values is uniform by using the χ 2 {\displaystyle \chi ^{2}} test to see if the distribution has a likelihood of happening of at least the significance level (conventionally 5%). The function should return a boolean that is true if the distribut...
#Tcl
Tcl
package require Tcl 8.5 package require math::statistics   proc isUniform {distribution {significance 0.05}} { set count [tcl::mathop::+ {*}[dict values $distribution]] set expected [expr {double($count) / [dict size $distribution]}] set X2 0.0 foreach value [dict values $distribution] { set X2 [expr {...
http://rosettacode.org/wiki/Vigen%C3%A8re_cipher
Vigenère cipher
Task Implement a   Vigenère cypher,   both encryption and decryption. The program should handle keys and text of unequal length, and should capitalize everything and discard non-alphabetic characters. (If your program handles non-alphabetic characters in another way, make a note of it.) Related tasks   Caesar ...
#Lua
Lua
function Encrypt( _msg, _key ) local msg = { _msg:upper():byte( 1, -1 ) } local key = { _key:upper():byte( 1, -1 ) } local enc = {}   local j, k = 1, 1 for i = 1, #msg do if msg[i] >= string.byte('A') and msg[i] <= string.byte('Z') then enc[k] = ( msg[i] + key[j] - 2*...
http://rosettacode.org/wiki/Visualize_a_tree
Visualize a tree
A tree structure   (i.e. a rooted, connected acyclic graph)   is often used in programming. It's often helpful to visually examine such a structure. There are many ways to represent trees to a reader, such as:   indented text   (à la unix tree command)   nested HTML tables   hierarchical GUI widgets   2D   or ...
#Ruby
Ruby
  root = BinaryTreeNode.from_array [1, [2, [4, 7], [5]], [3, [6, [8], [9]]]]  
http://rosettacode.org/wiki/Visualize_a_tree
Visualize a tree
A tree structure   (i.e. a rooted, connected acyclic graph)   is often used in programming. It's often helpful to visually examine such a structure. There are many ways to represent trees to a reader, such as:   indented text   (à la unix tree command)   nested HTML tables   hierarchical GUI widgets   2D   or ...
#Rust
Rust
  extern crate rustc_serialize; extern crate term_painter;   use rustc_serialize::json; use std::fmt::{Debug, Display, Formatter, Result}; use term_painter::ToStyle; use term_painter::Color::*;   type NodePtr = Option<usize>;   #[derive(Debug, PartialEq, Clone, Copy)] enum Side { Left, Right, Up, }   #[deri...
http://rosettacode.org/wiki/Walk_a_directory/Recursively
Walk a directory/Recursively
Task Walk a given directory tree and print files matching a given pattern. Note: This task is for recursive methods.   These tasks should read an entire directory tree, not a single directory. Note: Please be careful when running any code examples found here. Related task   Walk a directory/Non-recursively   ...
#Prolog_2
Prolog
% submitted by Aykayayciti (Earl Lamont Montgomery) % altered from fsaenzperez April 2019 % (swi-prolog.discourse-group) test_run :- proc_dir('C:\\vvvv\\vvvv_beta_39_x64').     proc_dir(Directory) :- format('Directory: ~w~n',[Directory]), directory_files(Directory,Files),!, %cut inserted proc_file...
http://rosettacode.org/wiki/Water_collected_between_towers
Water collected between towers
Task In a two-dimensional world, we begin with any bar-chart (or row of close-packed 'towers', each of unit width), and then it rains, completely filling all convex enclosures in the chart with water. 9 ██ 9 ██ 8 ██ 8 ██ 7 ██ ...
#Rust
Rust
  use std::cmp::min;   fn getfill(pattern: &[usize]) -> usize { let mut total = 0; for (idx, val) in pattern.iter().enumerate() { let l_peak = pattern[..idx].iter().max(); let r_peak = pattern[idx + 1..].iter().max(); if l_peak.is_some() && r_peak.is_some() { let peak = min(l...
http://rosettacode.org/wiki/Vector_products
Vector products
A vector is defined as having three dimensions as being represented by an ordered collection of three numbers:   (X, Y, Z). If you imagine a graph with the   x   and   y   axis being at right angles to each other and having a third,   z   axis coming out of the page, then a triplet of numbers,   (X, Y, Z)   would repr...
#AWK
AWK
#!/usr/bin/awk -f BEGIN { a[1] = 3; a[2]= 4; a[3] = 5; b[1] = 4; b[2]= 3; b[3] = 5; c[1] = -5; c[2]= -12; c[3] = -13;   print "a = ",printVec(a); print "b = ",printVec(b); print "c = ",printVec(c); print "a.b = ",dot(a,b); ## upper case variables are used as temporary or inte...
http://rosettacode.org/wiki/Validate_International_Securities_Identification_Number
Validate International Securities Identification Number
An International Securities Identification Number (ISIN) is a unique international identifier for a financial security such as a stock or bond. Task Write a function or program that takes a string as input, and checks whether it is a valid ISIN. It is only valid if it has the correct format,   and   the embedded c...
#360_Assembly
360 Assembly
* Validate ISIN 08/03/2019 VALISIN CSECT USING VALISIN,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/Validate_International_Securities_Identification_Number
Validate International Securities Identification Number
An International Securities Identification Number (ISIN) is a unique international identifier for a financial security such as a stock or bond. Task Write a function or program that takes a string as input, and checks whether it is a valid ISIN. It is only valid if it has the correct format,   and   the embedded c...
#Ada
Ada
procedure ISIN is -- Luhn_Test copied from other Task function Luhn_Test (Number: String) return Boolean is Sum  : Natural := 0; Odd  : Boolean := True; Digit: Natural range 0 .. 9; begin for p in reverse Number'Range loop Digit := Integer'Value (Number (p..p)); if Odd...
http://rosettacode.org/wiki/Variable_declaration_reset
Variable declaration reset
A decidely non-challenging task to highlight a potential difference between programming languages. Using a straightforward longhand loop as in the JavaScript and Phix examples below, show the locations of elements which are identical to the immediately preceding element in {1,2,2,3,4,4,5}. The (non-blank) results may ...
#jq
jq
[1,2,2,3,4,4,5] | . as $array | range(1;length) | select( $array[.] == $array[.-1])  
http://rosettacode.org/wiki/Variable_declaration_reset
Variable declaration reset
A decidely non-challenging task to highlight a potential difference between programming languages. Using a straightforward longhand loop as in the JavaScript and Phix examples below, show the locations of elements which are identical to the immediately preceding element in {1,2,2,3,4,4,5}. The (non-blank) results may ...
#Julia
Julia
  s = [1, 2, 2, 3, 4, 4, 5]   for i in eachindex(s) curr = s[i] i > 1 && curr == prev && println(i) prev = curr end  
http://rosettacode.org/wiki/Variable_declaration_reset
Variable declaration reset
A decidely non-challenging task to highlight a potential difference between programming languages. Using a straightforward longhand loop as in the JavaScript and Phix examples below, show the locations of elements which are identical to the immediately preceding element in {1,2,2,3,4,4,5}. The (non-blank) results may ...
#Perl
Perl
@s = <1 2 2 3 4 4 5>; for ($i = 0; $i < 7; $i++) { $curr = $s[$i]; if ($i > 1 and $curr == $prev) { print "$i\n" } $prev = $curr; }
http://rosettacode.org/wiki/Variable_declaration_reset
Variable declaration reset
A decidely non-challenging task to highlight a potential difference between programming languages. Using a straightforward longhand loop as in the JavaScript and Phix examples below, show the locations of elements which are identical to the immediately preceding element in {1,2,2,3,4,4,5}. The (non-blank) results may ...
#Phix
Phix
with javascript_semantics sequence s = {1,2,2,3,4,4,5} for i=1 to length(s) do integer curr = s[i], prev if i>1 and curr=prev then ?i end if prev = curr end for
http://rosettacode.org/wiki/Van_der_Corput_sequence
Van der Corput sequence
When counting integers in binary, if you put a (binary) point to the righEasyLangt of the count then the column immediately to the left denotes a digit with a multiplier of 2 0 {\displaystyle 2^{0}} ; the digit in the next column to the left has a multiplier of 2 1 {\displaystyle 2^{1}} ; and so o...
#ActionScript
ActionScript
  package {   import flash.display.Sprite; import flash.events.Event;   public class VanDerCorput extends Sprite {   public function VanDerCorput():void { if (stage) init(); else addEventListener(Event.ADDED_TO_STAGE, init); }   private function init(e:Event =...
http://rosettacode.org/wiki/Variables
Variables
Task Demonstrate a language's methods of:   variable declaration   initialization   assignment   datatypes   scope   referencing,     and   other variable related facilities
#AArch64_Assembly
AArch64 Assembly
  /* ARM assembly AARCH64 Raspberry PI 3B */ /* program variable64.s */   /*******************************************/ /* Constantes file */ /*******************************************/ /* for this file see task include a file in language AArch64 assembly*/ .include "../includeConstantesARM...
http://rosettacode.org/wiki/Van_Eck_sequence
Van Eck sequence
The sequence is generated by following this pseudo-code: A: The first term is zero. Repeatedly apply: If the last term is *new* to the sequence so far then: B: The next term is zero. Otherwise: C: The next term is how far back this last term occured previously. Example Using ...
#ALGOL_68
ALGOL 68
BEGIN # find elements of the Van Eck Sequence - first term is 0, following # # terms are 0 if the previous was the first appearance of the element # # or how far back in the sequence the last element appeared # # returns the first n elements of the Van Eck sequence # OP V...
http://rosettacode.org/wiki/Vampire_number
Vampire number
A vampire number is a natural decimal number with an even number of digits,   that can be factored into two integers. These two factors are called the   fangs,   and must have the following properties:   they each contain half the number of the decimal digits of the original number   together they consist of exactl...
#C.23
C#
using System;   namespace RosettaVampireNumber { class Program { static void Main(string[] args) { int i, j, n; ulong x; var f = new ulong[16]; var bigs = new ulong[] { 16758243290880UL, 24959017348650UL, 14593825548650UL, 0 }; ulong[] ...
http://rosettacode.org/wiki/Variable-length_quantity
Variable-length quantity
Implement some operations on variable-length quantities, at least including conversions from a normal number in the language to the binary representation of the variable-length quantity for that number, and vice versa. Any variants are acceptable. Task With above operations, convert these two numbers 0x200000 (209...
#Phix
Phix
function vlq_encode(sequence s) sequence res = {} for i=length(s) to 1 by -1 do integer n = s[i], msb = 0 if n<0 then crash("unsigned integers only!") end if while 1 do res = prepend(res,msb+and_bits(n,#7F)) n = floor(n/#80) if n=0 then exit end if ...
http://rosettacode.org/wiki/Variadic_function
Variadic function
Task Create a function which takes in a variable number of arguments and prints each one on its own line. Also show, if possible in your language, how to call the function on a list of arguments constructed at runtime. Functions of this type are also known as Variadic Functions. Related task   Call a function...
#Dyalect
Dyalect
func printAll(args...) { for i in args { print(i) } }   printAll("test", "rosetta code", 123, 5.6)
http://rosettacode.org/wiki/Variadic_function
Variadic function
Task Create a function which takes in a variable number of arguments and prints each one on its own line. Also show, if possible in your language, how to call the function on a list of arguments constructed at runtime. Functions of this type are also known as Variadic Functions. Related task   Call a function...
#D.C3.A9j.C3.A0_Vu
Déjà Vu
show-all(: while /= ) dup:  !. drop   show-all( :foo "Hello" 42 [ true ] )
http://rosettacode.org/wiki/Variable_size/Get
Variable size/Get
Demonstrate how to get the size of a variable. See also: Host introspection
#Free_Pascal
Free Pascal
' FB 1.05.0 Win64   Dim i As Integer Dim l As Long Dim s As Short Dim b As Byte Print "An integer occupies "; SizeOf(i); " bytes" Print "A long occupies "; SizeOf(l); " bytes" Print "A short occupies "; SizeOf(s); " bytes" Print "A byte occupies "; SizeOf(b); " byte"   ' or use type directly rather than a va...
http://rosettacode.org/wiki/Variable_size/Get
Variable size/Get
Demonstrate how to get the size of a variable. See also: Host introspection
#FreeBASIC
FreeBASIC
' FB 1.05.0 Win64   Dim i As Integer Dim l As Long Dim s As Short Dim b As Byte Print "An integer occupies "; SizeOf(i); " bytes" Print "A long occupies "; SizeOf(l); " bytes" Print "A short occupies "; SizeOf(s); " bytes" Print "A byte occupies "; SizeOf(b); " byte"   ' or use type directly rather than a va...
http://rosettacode.org/wiki/Vector
Vector
Task Implement a Vector class (or a set of functions) that models a Physical Vector. The four basic operations and a pretty print function should be implemented. The Vector may be initialized in any reasonable way. Start and end points, and direction Angular coefficient and value (length) The four operations to...
#Kotlin
Kotlin
// version 1.1.2   class Vector2D(val x: Double, val y: Double) { operator fun plus(v: Vector2D) = Vector2D(x + v.x, y + v.y)   operator fun minus(v: Vector2D) = Vector2D(x - v.x, y - v.y)   operator fun times(s: Double) = Vector2D(s * x, s * y)   operator fun div(s: Double) = Vector2D(x / s, y / s)   ...
http://rosettacode.org/wiki/Verify_distribution_uniformity/Chi-squared_test
Verify distribution uniformity/Chi-squared test
Task Write a function to verify that a given distribution of values is uniform by using the χ 2 {\displaystyle \chi ^{2}} test to see if the distribution has a likelihood of happening of at least the significance level (conventionally 5%). The function should return a boolean that is true if the distribut...
#VBA
VBA
Private Function Test4DiscreteUniformDistribution(ObservationFrequencies() As Variant, Significance As Single) As Boolean 'Returns true if the observed frequencies pass the Pearson Chi-squared test at the required significance level. Dim Total As Long, Ei As Long, i As Integer Dim ChiSquared As Double, Degr...
http://rosettacode.org/wiki/Verify_distribution_uniformity/Chi-squared_test
Verify distribution uniformity/Chi-squared test
Task Write a function to verify that a given distribution of values is uniform by using the χ 2 {\displaystyle \chi ^{2}} test to see if the distribution has a likelihood of happening of at least the significance level (conventionally 5%). The function should return a boolean that is true if the distribut...
#Vlang
Vlang
import math   type Ifctn = fn(f64) f64   fn simpson38(f Ifctn, a f64, b f64, n int) f64 { h := (b - a) / f64(n) h1 := h / 3 mut sum := f(a) + f(b) for j := 3*n - 1; j > 0; j-- { if j%3 == 0 { sum += 2 * f(a+h1*f64(j)) } else { sum += 3 * f(a+h1*f64(j)) } ...
http://rosettacode.org/wiki/Vigen%C3%A8re_cipher
Vigenère cipher
Task Implement a   Vigenère cypher,   both encryption and decryption. The program should handle keys and text of unequal length, and should capitalize everything and discard non-alphabetic characters. (If your program handles non-alphabetic characters in another way, make a note of it.) Related tasks   Caesar ...
#Mathematica.2FWolfram_Language
Mathematica/Wolfram Language
encode[text_String, key_String] := Module[{textCode, keyCode}, textCode = Cases[ToCharacterCode[ ToUpperCase@ text], _?(IntervalMemberQ[Interval@{65, 90}, #] &)] - 65; keyCode = Cases[ToCharacterCode[ ToUpperCase@ key], _?(IntervalMemberQ[Interval@{65, 90}, #] &)] - 65; keyCode...
http://rosettacode.org/wiki/Visualize_a_tree
Visualize a tree
A tree structure   (i.e. a rooted, connected acyclic graph)   is often used in programming. It's often helpful to visually examine such a structure. There are many ways to represent trees to a reader, such as:   indented text   (à la unix tree command)   nested HTML tables   hierarchical GUI widgets   2D   or ...
#Sidef
Sidef
func visualize_tree(tree, label, children, indent = '', mids = ['├─', '│ '], ends = ['└─', ' '], ) { func visit(node, pre) { gather { take(pre[0] + label(node)) var chldn = children(node) var end = chldn.end ...
http://rosettacode.org/wiki/Walk_a_directory/Recursively
Walk a directory/Recursively
Task Walk a given directory tree and print files matching a given pattern. Note: This task is for recursive methods.   These tasks should read an entire directory tree, not a single directory. Note: Please be careful when running any code examples found here. Related task   Walk a directory/Non-recursively   ...
#Python
Python
  from pathlib import Path   for path in Path('.').rglob('*.*'): print(path)  
http://rosettacode.org/wiki/Walk_a_directory/Recursively
Walk a directory/Recursively
Task Walk a given directory tree and print files matching a given pattern. Note: This task is for recursive methods.   These tasks should read an entire directory tree, not a single directory. Note: Please be careful when running any code examples found here. Related task   Walk a directory/Non-recursively   ...
#R
R
dir("/bar/foo", "mp3",recursive=T)
http://rosettacode.org/wiki/Water_collected_between_towers
Water collected between towers
Task In a two-dimensional world, we begin with any bar-chart (or row of close-packed 'towers', each of unit width), and then it rains, completely filling all convex enclosures in the chart with water. 9 ██ 9 ██ 8 ██ 8 ██ 7 ██ ...
#Scala
Scala
import scala.collection.parallel.CollectionConverters.VectorIsParallelizable   // Program to find maximum amount of water // that can be trapped within given set of bars. object TrappedWater extends App { private val barLines = List( Vector(1, 5, 3, 7, 2), Vector(5, 3, 7, 2, 6, 4, 5, 9, 1, 2), Vector(2, 6...
http://rosettacode.org/wiki/Vector_products
Vector products
A vector is defined as having three dimensions as being represented by an ordered collection of three numbers:   (X, Y, Z). If you imagine a graph with the   x   and   y   axis being at right angles to each other and having a third,   z   axis coming out of the page, then a triplet of numbers,   (X, Y, Z)   would repr...
#BASIC256
BASIC256
  a={3,4,5}:b={4,3,5}:c={-5,-12,-13}   print "A.B = "+dot_product(ref(a),ref(b)) call cross_product(ref(a),ref(b),ref(y)) Print "AxB = ("+y[0]+","+y[1]+","+y[2]+")" print "A.(BxC) = "+s_tri(ref(a),ref(b),ref(c)) call v_tri(ref(a),ref(b),ref(c),ref(x),ref(y)) Print "A x (BxC) = ("+y[0]+","+y[1]+","+y[2]+")"   function ...
http://rosettacode.org/wiki/Validate_International_Securities_Identification_Number
Validate International Securities Identification Number
An International Securities Identification Number (ISIN) is a unique international identifier for a financial security such as a stock or bond. Task Write a function or program that takes a string as input, and checks whether it is a valid ISIN. It is only valid if it has the correct format,   and   the embedded c...
#ALGOL_W
ALGOL W
begin  % external procedure that returns true if ccNumber passes the Luhn test, false otherwise % logical procedure LuhnTest ( string(32) value ccNumber  ; integer value ccLength ) ; algol "LUHN" ;    % returns true if isin is a valid ISIN, false...
http://rosettacode.org/wiki/Validate_International_Securities_Identification_Number
Validate International Securities Identification Number
An International Securities Identification Number (ISIN) is a unique international identifier for a financial security such as a stock or bond. Task Write a function or program that takes a string as input, and checks whether it is a valid ISIN. It is only valid if it has the correct format,   and   the embedded c...
#AppleScript
AppleScript
use AppleScript version "2.4" -- OS X 10.10 (Yosemite) or later use framework "Foundation"   on ISINTest(ISIN) -- Check that the input is both text and 12 characters long … if not ((ISIN's class is text) and ((count ISIN) is 12)) then return false -- … and that it has the required format. set ISIN to cu...
http://rosettacode.org/wiki/Variable_declaration_reset
Variable declaration reset
A decidely non-challenging task to highlight a potential difference between programming languages. Using a straightforward longhand loop as in the JavaScript and Phix examples below, show the locations of elements which are identical to the immediately preceding element in {1,2,2,3,4,4,5}. The (non-blank) results may ...
#PL.2FM
PL/M
100H:   /* CP/M BDOS SYSTEM CALL */ BDOS: PROCEDURE( FN, ARG ); DECLARE FN BYTE, ARG ADDRESS; GOTO 5;END; /* CONSOLE OUTPUT ROUTINES */ PR$CHAR: PROCEDURE( C ); DECLARE C BYTE; CALL BDOS( 2, C ); END; PR$STRING: PROCEDURE( S ); DECLARE S ADDRESS; CALL BDOS( 9, S ); END; PR$NL: PROCEDURE; CALL...
http://rosettacode.org/wiki/Van_der_Corput_sequence
Van der Corput sequence
When counting integers in binary, if you put a (binary) point to the righEasyLangt of the count then the column immediately to the left denotes a digit with a multiplier of 2 0 {\displaystyle 2^{0}} ; the digit in the next column to the left has a multiplier of 2 1 {\displaystyle 2^{1}} ; and so o...
#Ada
Ada
with Ada.Text_IO;   procedure Main is package Float_IO is new Ada.Text_IO.Float_IO (Float); function Van_Der_Corput (N : Natural; Base : Positive := 2) return Float is Value  : Natural  := N; Result  : Float  := 0.0; Exponent : Positive := 1; begin while Value > 0 loop Res...
http://rosettacode.org/wiki/Van_der_Corput_sequence
Van der Corput sequence
When counting integers in binary, if you put a (binary) point to the righEasyLangt of the count then the column immediately to the left denotes a digit with a multiplier of 2 0 {\displaystyle 2^{0}} ; the digit in the next column to the left has a multiplier of 2 1 {\displaystyle 2^{1}} ; and so o...
#AutoHotkey
AutoHotkey
SetFormat, FloatFast, 0.5 for i, v in [2, 3, 4, 5, 6] { seq .= "Base " v ": " Loop, 10 seq .= VanDerCorput(A_Index - 1, v) (A_Index = 10 ? "`n" : ", ") } MsgBox, % seq   VanDerCorput(n, b, r=0) { while n r += Mod(n, b) * b ** -A_Index, n := n // b return, r }
http://rosettacode.org/wiki/Variables
Variables
Task Demonstrate a language's methods of:   variable declaration   initialization   assignment   datatypes   scope   referencing,     and   other variable related facilities
#Ada
Ada
Name: declare -- a local declaration block has an optional name A : constant Integer := 42; -- Create a constant X : String := "Hello"; -- Create and initialize a local variable Y : Integer; -- Create an uninitialized variable Z : Integer renames Y: -- Rename Y (creates a view) function F (X...
http://rosettacode.org/wiki/Van_Eck_sequence
Van Eck sequence
The sequence is generated by following this pseudo-code: A: The first term is zero. Repeatedly apply: If the last term is *new* to the sequence so far then: B: The next term is zero. Otherwise: C: The next term is how far back this last term occured previously. Example Using ...
#ALGOL-M
ALGOL-M
begin integer array eck[1:1000]; integer i, j;   for i := 1 step 1 until 1000 do eck[i] := 0;   for i := 1 step 1 until 999 do begin j := i - 1; while j > 0 and eck[i] <> eck[j] do j := j - 1; if j <> 0 then eck[i+1] := i - j; end;   for i := 1 step 1 until 10 do writeon(eck[i]); wr...
http://rosettacode.org/wiki/Van_Eck_sequence
Van Eck sequence
The sequence is generated by following this pseudo-code: A: The first term is zero. Repeatedly apply: If the last term is *new* to the sequence so far then: B: The next term is zero. Otherwise: C: The next term is how far back this last term occured previously. Example Using ...
#ALGOL_W
ALGOL W
begin % find elements of the Van Eck Sequence - first term is 0, following  %  % terms are 0 if the previous was the first appearance of the element %  % or how far back in the sequence the last element appeared  %  % sets s to the first n elements of the Van Eck sequence  % proc...
http://rosettacode.org/wiki/Vampire_number
Vampire number
A vampire number is a natural decimal number with an even number of digits,   that can be factored into two integers. These two factors are called the   fangs,   and must have the following properties:   they each contain half the number of the decimal digits of the original number   together they consist of exactl...
#C.2B.2B
C++
#include <vector> #include <utility> #include <algorithm> #include <iostream> #include <sstream> #include <string> #include <cmath>   bool isVampireNumber( long number, std::vector<std::pair<long, long> > & solution ) { std::ostringstream numberstream ; numberstream << number ; std::string numberstring( number...
http://rosettacode.org/wiki/Variable-length_quantity
Variable-length quantity
Implement some operations on variable-length quantities, at least including conversions from a normal number in the language to the binary representation of the variable-length quantity for that number, and vice versa. Any variants are acceptable. Task With above operations, convert these two numbers 0x200000 (209...
#PicoLisp
PicoLisp
(de numToVlq (Num) (let Res (cons (& Num 127)) (while (gt0 (setq Num (>> 7 Num))) (push 'Res (| 128 (& Num 127))) ) Res ) )   (de vlqToNum (Vlq) (let Res 0 (for N Vlq (setq Res (| (>> -7 Res) (& N 127))) ) ) )   (for Num (0 15 16 127 128 255 2097151 2097152) (let Vlq (numToV...
http://rosettacode.org/wiki/Variable-length_quantity
Variable-length quantity
Implement some operations on variable-length quantities, at least including conversions from a normal number in the language to the binary representation of the variable-length quantity for that number, and vice versa. Any variants are acceptable. Task With above operations, convert these two numbers 0x200000 (209...
#PL.2FI
PL/I
  test: procedure options(main); declare s character (20) varying; declare c character (1); declare v fixed binary (31); declare (i, k) fixed binary;   get edit (s) (L); s = trim (s); v = 0; do i = 1 to length(s); c = substr(s, i, 1); k = index('0123456789abcdef', c); if k > 0 ...
http://rosettacode.org/wiki/Variable-length_quantity
Variable-length quantity
Implement some operations on variable-length quantities, at least including conversions from a normal number in the language to the binary representation of the variable-length quantity for that number, and vice versa. Any variants are acceptable. Task With above operations, convert these two numbers 0x200000 (209...
#Python
Python
def tobits(n, _group=8, _sep='_', _pad=False): 'Express n as binary bits with separator' bits = '{0:b}'.format(n)[::-1] if _pad: bits = '{0:0{1}b}'.format(n, ((_group+len(bits)-1)//_group)*_group)[::-1] answer = _sep.join(bits[i:i+_group] ...
http://rosettacode.org/wiki/Variadic_function
Variadic function
Task Create a function which takes in a variable number of arguments and prints each one on its own line. Also show, if possible in your language, how to call the function on a list of arguments constructed at runtime. Functions of this type are also known as Variadic Functions. Related task   Call a function...
#E
E
def example { match [`run`, args] { for x in args { println(x) } } }   example("Mary", "had", "a", "little", "lamb")   E.call(example, "run", ["Mary", "had", "a", "little", "lamb"])
http://rosettacode.org/wiki/Variadic_function
Variadic function
Task Create a function which takes in a variable number of arguments and prints each one on its own line. Also show, if possible in your language, how to call the function on a list of arguments constructed at runtime. Functions of this type are also known as Variadic Functions. Related task   Call a function...
#Egel
Egel
  [ X Y -> "two" | X -> "one" | -> "zero" ]  
http://rosettacode.org/wiki/Variable_size/Get
Variable size/Get
Demonstrate how to get the size of a variable. See also: Host introspection
#Gambas
Gambas
Public Sub Main()   Print "Boolean =\t " & SizeOf(gb.Boolean) Print "Byte =\t\t " & SizeOf(gb.Byte) Print "Short =\t\t " & SizeOf(gb.Short) Print "Integer =\t " & SizeOf(gb.Integer) Print "Single =\t " & SizeOf(gb.Single) Print "Long =\t\t " & SizeOf(gb.Long) Print "Float =\t\t " & SizeOf(gb.Float) Print "Date =\t\t " ...
http://rosettacode.org/wiki/Variable_size/Get
Variable size/Get
Demonstrate how to get the size of a variable. See also: Host introspection
#Go
Go
import "unsafe"   unsafe.Sizeof(x)
http://rosettacode.org/wiki/Vector
Vector
Task Implement a Vector class (or a set of functions) that models a Physical Vector. The four basic operations and a pretty print function should be implemented. The Vector may be initialized in any reasonable way. Start and end points, and direction Angular coefficient and value (length) The four operations to...
#Lua
Lua
vector = {mt = {}}   function vector.new (x, y) local new = {x = x or 0, y = y or 0} setmetatable(new, vector.mt) return new end   function vector.mt.__add (v1, v2) return vector.new(v1.x + v2.x, v1.y + v2.y) end   function vector.mt.__sub (v1, v2) return vector.new(v1.x - v2.x, v1.y - v2.y) end   ...
http://rosettacode.org/wiki/Verify_distribution_uniformity/Chi-squared_test
Verify distribution uniformity/Chi-squared test
Task Write a function to verify that a given distribution of values is uniform by using the χ 2 {\displaystyle \chi ^{2}} test to see if the distribution has a likelihood of happening of at least the significance level (conventionally 5%). The function should return a boolean that is true if the distribut...
#Wren
Wren
import "/math" for Math, Nums import "/fmt" for Fmt   var integrate = Fn.new { |a, b, n, f| var h = (b - a) / n var sum = 0 for (i in 0...n) { var x = a + i*h sum = sum + (f.call(x) + 4 * f.call(x + h/2) + f.call(x + h)) / 6 } return sum * h }   var gammaIncomplete = Fn.new { |a, x...
http://rosettacode.org/wiki/Vigen%C3%A8re_cipher
Vigenère cipher
Task Implement a   Vigenère cypher,   both encryption and decryption. The program should handle keys and text of unequal length, and should capitalize everything and discard non-alphabetic characters. (If your program handles non-alphabetic characters in another way, make a note of it.) Related tasks   Caesar ...
#NetRexx
NetRexx
/* NetRexx */ options replace format comments java crossref savelog symbols nobinary   pt = 'Attack at dawn!' key = 'LEMON' test(key, pt)   key = 'N' -- rot-13 test(key, pt)   key = 'B' -- Caesar test(key, pt)   pt = 'ABCDEFGHIJKLMNOPQRSTUVWXYZ' key = 'A' test(key, pt)   pt = sampledata() key = 'Hamlet; Prince of Denm...
http://rosettacode.org/wiki/Visualize_a_tree
Visualize a tree
A tree structure   (i.e. a rooted, connected acyclic graph)   is often used in programming. It's often helpful to visually examine such a structure. There are many ways to represent trees to a reader, such as:   indented text   (à la unix tree command)   nested HTML tables   hierarchical GUI widgets   2D   or ...
#Tcl
Tcl
package require struct::tree   proc visualize_tree {tree {nameattr name}} { set path {} $tree walk [$tree rootname] -order both {mode node} { if {$mode eq "enter"} { set s "" foreach p $path { append s [expr {[$tree next $p] eq "" ? " " : "\u2502 "}] } lappend path $node append s [e...
http://rosettacode.org/wiki/Walk_a_directory/Recursively
Walk a directory/Recursively
Task Walk a given directory tree and print files matching a given pattern. Note: This task is for recursive methods.   These tasks should read an entire directory tree, not a single directory. Note: Please be careful when running any code examples found here. Related task   Walk a directory/Non-recursively   ...
#Racket
Racket
  -> (for ([f (in-directory "/tmp")] #:when (regexp-match? "\\.rkt$" f)) (displayln f)) ... *.rkt files including in nested directories ...  
http://rosettacode.org/wiki/Walk_a_directory/Recursively
Walk a directory/Recursively
Task Walk a given directory tree and print files matching a given pattern. Note: This task is for recursive methods.   These tasks should read an entire directory tree, not a single directory. Note: Please be careful when running any code examples found here. Related task   Walk a directory/Non-recursively   ...
#Raku
Raku
use File::Find;   .say for find dir => '.', name => /'.txt' $/;
http://rosettacode.org/wiki/Water_collected_between_towers
Water collected between towers
Task In a two-dimensional world, we begin with any bar-chart (or row of close-packed 'towers', each of unit width), and then it rains, completely filling all convex enclosures in the chart with water. 9 ██ 9 ██ 8 ██ 8 ██ 7 ██ ...
#Scheme
Scheme
(import (scheme base) (scheme write))   (define (total-collected chart) (define (highest-left vals curr) (if (null? vals) (list curr) (cons curr (highest-left (cdr vals) (max (car vals) curr))))) (define (highest-right vals curr) (reverse (highest-left (reverse vals) curr))) ...
http://rosettacode.org/wiki/Vector_products
Vector products
A vector is defined as having three dimensions as being represented by an ordered collection of three numbers:   (X, Y, Z). If you imagine a graph with the   x   and   y   axis being at right angles to each other and having a third,   z   axis coming out of the page, then a triplet of numbers,   (X, Y, Z)   would repr...
#BBC_BASIC
BBC BASIC
DIM a(2), b(2), c(2), d(2) a() = 3, 4, 5 b() = 4, 3, 5 c() = -5, -12, -13   PRINT "a . b = "; FNdot(a(),b()) PROCcross(a(),b(),d()) PRINT "a x b = (";d(0)", ";d(1)", ";d(2)")" PRINT "a . (b x c) = "; FNscalartriple(a(),b(),c()) PROCvectortriple(a(),b(),c(),d()) ...
http://rosettacode.org/wiki/Validate_International_Securities_Identification_Number
Validate International Securities Identification Number
An International Securities Identification Number (ISIN) is a unique international identifier for a financial security such as a stock or bond. Task Write a function or program that takes a string as input, and checks whether it is a valid ISIN. It is only valid if it has the correct format,   and   the embedded c...
#AWK
AWK
  # syntax: GAWK -f VALIDATE_INTERNATIONAL_SECURITIES_IDENTIFICATION_NUMBER.AWK # converted from Fortran BEGIN { for (i=0; i<=255; i++) { ord_arr[sprintf("%c",i)] = i } # build array[character]=ordinal_value n = split("US0378331005,US0373831005,U50378331005,US03378331005,AU0000XVGZA3,AU0000VXGZA3,FR0000988040",...
http://rosettacode.org/wiki/Variable_declaration_reset
Variable declaration reset
A decidely non-challenging task to highlight a potential difference between programming languages. Using a straightforward longhand loop as in the JavaScript and Phix examples below, show the locations of elements which are identical to the immediately preceding element in {1,2,2,3,4,4,5}. The (non-blank) results may ...
#Python
Python
  s = [1, 2, 2, 3, 4, 4, 5]   for i in range(len(s)): curr = s[i] if i > 0 and curr == prev: print(i) prev = curr  
http://rosettacode.org/wiki/Variable_declaration_reset
Variable declaration reset
A decidely non-challenging task to highlight a potential difference between programming languages. Using a straightforward longhand loop as in the JavaScript and Phix examples below, show the locations of elements which are identical to the immediately preceding element in {1,2,2,3,4,4,5}. The (non-blank) results may ...
#Raku
Raku
my @s = 1, 2, 2, 3, 4, 4, 5; loop (my $i = 0; $i < 7; $i += 1) { my $curr = @s[$i]; my $prev; if $i > 1 and $curr == $prev { say $i; } $prev = $curr; }
http://rosettacode.org/wiki/Variable_declaration_reset
Variable declaration reset
A decidely non-challenging task to highlight a potential difference between programming languages. Using a straightforward longhand loop as in the JavaScript and Phix examples below, show the locations of elements which are identical to the immediately preceding element in {1,2,2,3,4,4,5}. The (non-blank) results may ...
#Red
Red
Red[] s: [1 2 2 3 4 4 5] repeat i length? s [ curr: s/:i if all [i > 1 curr = prev][ print i ] prev: curr ]
http://rosettacode.org/wiki/Van_der_Corput_sequence
Van der Corput sequence
When counting integers in binary, if you put a (binary) point to the righEasyLangt of the count then the column immediately to the left denotes a digit with a multiplier of 2 0 {\displaystyle 2^{0}} ; the digit in the next column to the left has a multiplier of 2 1 {\displaystyle 2^{1}} ; and so o...
#AWK
AWK
  # syntax: GAWK -f VAN_DER_CORPUT_SEQUENCE.AWK # converted from BBC BASIC BEGIN { printf("base") for (i=0; i<=9; i++) { printf(" %7d",i) } printf("\n") for (base=2; base<=5; base++) { printf("%-4s",base) for (i=0; i<=9; i++) { printf(" %7.5f",vdc(i,base)) } pri...
http://rosettacode.org/wiki/Van_der_Corput_sequence
Van der Corput sequence
When counting integers in binary, if you put a (binary) point to the righEasyLangt of the count then the column immediately to the left denotes a digit with a multiplier of 2 0 {\displaystyle 2^{0}} ; the digit in the next column to the left has a multiplier of 2 1 {\displaystyle 2^{1}} ; and so o...
#BASIC
BASIC
10 DEFINT A-Z 20 FOR B=2 TO 5 30 PRINT USING "BASE #:";B; 40 FOR I=0 TO 9 50 P=0: Q=1: N=I 60 IF N=0 GOTO 110 70 P=P*B+N MOD B 80 Q=Q*B 90 N=N\B 100 GOTO 60 110 X=P: Y=Q 120 IF P=0 GOTO 150 130 N=P: P=Q MOD P: Q=N 140 GOTO 120 150 X=X\Q 160 Y=Y\Q 170 IF X=0 THEN PRINT " 0"; ELSE PRINT USING " ##/##";X;Y; 180 NEXT I ...
http://rosettacode.org/wiki/Variables
Variables
Task Demonstrate a language's methods of:   variable declaration   initialization   assignment   datatypes   scope   referencing,     and   other variable related facilities
#ALGOL_68
ALGOL 68
int j;
http://rosettacode.org/wiki/Variables
Variables
Task Demonstrate a language's methods of:   variable declaration   initialization   assignment   datatypes   scope   referencing,     and   other variable related facilities
#ALGOL_W
ALGOL W
% declare some variables % integer a1, a2; real b; long real c; complex d; long complex f; logical g; bits h; string(32) j;   % assign "initial values" % f := d := c := b := a2 := a1 := 0; % multiple assignment % g := false; h := #a0; j := "Hello, World!";  
http://rosettacode.org/wiki/Van_Eck_sequence
Van Eck sequence
The sequence is generated by following this pseudo-code: A: The first term is zero. Repeatedly apply: If the last term is *new* to the sequence so far then: B: The next term is zero. Otherwise: C: The next term is how far back this last term occured previously. Example Using ...
#APL
APL
(10∘↑,[.5]¯10∘↑)(⊢,(⊃∘⌽∊¯1∘↓)∧(1↓⌽)⍳⊃∘⌽)⍣999⊢,0
http://rosettacode.org/wiki/Van_Eck_sequence
Van Eck sequence
The sequence is generated by following this pseudo-code: A: The first term is zero. Repeatedly apply: If the last term is *new* to the sequence so far then: B: The next term is zero. Otherwise: C: The next term is how far back this last term occured previously. Example Using ...
#AppleScript
AppleScript
use AppleScript version "2.4" use scripting additions     -- vanEck :: Int -> [Int] on vanEck(n) -- First n terms of the vanEck sequence.   script go on |λ|(xns, i) set {x, ns} to xns set prev to item (1 + x) of ns   if 0 ≠ prev then set v to i - prev ...
http://rosettacode.org/wiki/Vampire_number
Vampire number
A vampire number is a natural decimal number with an even number of digits,   that can be factored into two integers. These two factors are called the   fangs,   and must have the following properties:   they each contain half the number of the decimal digits of the original number   together they consist of exactl...
#Clojure
Clojure
(defn factor-pairs [n] (for [x (range 2 (Math/sqrt n))  :when (zero? (mod n x))] [x (quot n x)]))   (defn fangs [n] (let [dlen (comp count str) half (/ (dlen n) 2) halves? #(apply = (cons half (map dlen %))) digits #(sort (apply str %))] (filter #(and (halves? %) ...
http://rosettacode.org/wiki/Variable-length_quantity
Variable-length quantity
Implement some operations on variable-length quantities, at least including conversions from a normal number in the language to the binary representation of the variable-length quantity for that number, and vice versa. Any variants are acceptable. Task With above operations, convert these two numbers 0x200000 (209...
#Racket
Racket
  #lang racket   (define (try n) (printf "Original number: ~s (0x~x)\n" n n) (define 4octets (integer->integer-bytes n 4 #f)) (printf "Octets: ~a (byte-string: ~s)\n" (string-join (map (λ(o) (~r o #:base 16)) (bytes->list 4octets)) ":") 4octet...
http://rosettacode.org/wiki/Variable-length_quantity
Variable-length quantity
Implement some operations on variable-length quantities, at least including conversions from a normal number in the language to the binary representation of the variable-length quantity for that number, and vice versa. Any variants are acceptable. Task With above operations, convert these two numbers 0x200000 (209...
#Raku
Raku
sub vlq_encode ($number is copy) { my $string = ''; my $t = 0x7F +& $number; $number +>= 7; $string = $t.chr ~ $string; while ($number) { $t = 0x7F +& $number; $string = (0x80 +| $t).chr ~ $string; $number +>= 7; } return $string; }   sub vlq_decode ($string is copy) { ...
http://rosettacode.org/wiki/Variadic_function
Variadic function
Task Create a function which takes in a variable number of arguments and prints each one on its own line. Also show, if possible in your language, how to call the function on a list of arguments constructed at runtime. Functions of this type are also known as Variadic Functions. Related task   Call a function...
#Elena
Elena
import system'routines; import extensions;   extension variadicOp { printAll(params object[] list) { for(int i := 0, i < list.Length, i+=1) { self.printLine(list[i]) } } }   public program() { console.printAll("test", "rosetta code", 123, 5.6r) }
http://rosettacode.org/wiki/Variadic_function
Variadic function
Task Create a function which takes in a variable number of arguments and prints each one on its own line. Also show, if possible in your language, how to call the function on a list of arguments constructed at runtime. Functions of this type are also known as Variadic Functions. Related task   Call a function...
#Elixir
Elixir
defmodule RC do def print_each( arguments ) do Enum.each(arguments, fn x -> IO.inspect x end) end end   RC.print_each([1,2,3]) RC.print_each(["Mary", "had", "a", "little", "lamb"])
http://rosettacode.org/wiki/Variable_size/Get
Variable size/Get
Demonstrate how to get the size of a variable. See also: Host introspection
#Haskell
Haskell
import Foreign   sizeOf (undefined :: Int) -- size of Int in bytes (4 on mine) sizeOf (undefined :: Double) -- size of Double in bytes (8 on mine) sizeOf (undefined :: Bool) -- size of Bool in bytes (4 on mine) sizeOf (undefined :: Ptr a) -- size of Ptr in bytes (4 on mine)
http://rosettacode.org/wiki/Variable_size/Get
Variable size/Get
Demonstrate how to get the size of a variable. See also: Host introspection
#Icon_and_Unicon
Icon and Unicon
record rec0() record rec4(a,b,c,d)   procedure main() # get size   every i := seq(1) do { a0 := &allocated x := case i of { 1 : "ABCDEFGH" 2 : reverse(x) 10 : &digits 11 : x--x 20 : [] 21 : [1,2] 22 : [1,2,3] ...
http://rosettacode.org/wiki/Vector
Vector
Task Implement a Vector class (or a set of functions) that models a Physical Vector. The four basic operations and a pretty print function should be implemented. The Vector may be initialized in any reasonable way. Start and end points, and direction Angular coefficient and value (length) The four operations to...
#Maple
Maple
module MyVector() option object; local value := Vector();   export ModuleApply::static := proc( ) Object( MyVector, _passed ); end proc;   export ModuleCopy::static := proc( mv::MyVector, proto::MyVector, v::Vector, $ ) mv:-value := v; end proc;   export ModulePrint::static := proc(mv::...
http://rosettacode.org/wiki/Vector
Vector
Task Implement a Vector class (or a set of functions) that models a Physical Vector. The four basic operations and a pretty print function should be implemented. The Vector may be initialized in any reasonable way. Start and end points, and direction Angular coefficient and value (length) The four operations to...
#Mathematica_.2F_Wolfram_Language
Mathematica / Wolfram Language
ClearAll[vector,PrintVector] vector[{r_,\[Theta]_}]:=vector@@AngleVector[{r,\[Theta]}] vector[x_,y_]+vector[w_,z_]^:=vector[x+w,y+z] a_ vector[x_,y_]^:=vector[a x,a y] vector[x_,y_]-vector[w_,z_]^:=vector[x-w,y-z] PrintVector[vector[x_,y_]]:=Print["vector has first component: ",x," And second component: ",y]   vector[1...
http://rosettacode.org/wiki/Verify_distribution_uniformity/Chi-squared_test
Verify distribution uniformity/Chi-squared test
Task Write a function to verify that a given distribution of values is uniform by using the χ 2 {\displaystyle \chi ^{2}} test to see if the distribution has a likelihood of happening of at least the significance level (conventionally 5%). The function should return a boolean that is true if the distribut...
#zkl
zkl
/* Numerical integration method */ fcn Simpson3_8(f,a,b,N){ // fcn,double,double,Int --> double h,h1:=(b - a)/N, h/3.0; h*[1..3*N - 1].reduce('wrap(sum,j){ l1:=(if(j%3) 3.0 else 2.0); sum + l1*f(a + h1*j); },f(a) + f(b))/8.0; }   const A=12; fcn Gamma_Spouge(z){ // double --> double var coefs=...
http://rosettacode.org/wiki/Vigen%C3%A8re_cipher
Vigenère cipher
Task Implement a   Vigenère cypher,   both encryption and decryption. The program should handle keys and text of unequal length, and should capitalize everything and discard non-alphabetic characters. (If your program handles non-alphabetic characters in another way, make a note of it.) Related tasks   Caesar ...
#Nim
Nim
import strutils   proc encrypt(msg, key: string): string = var pos = 0 for c in msg: if c in Letters: result.add chr(((ord(key[pos]) + ord(c.toUpperAscii)) mod 26) + ord('A')) pos = (pos + 1) mod key.len   proc decrypt(msg, key: string): string = var pos = 0 for c in msg: result.add chr(((26...
http://rosettacode.org/wiki/Vigen%C3%A8re_cipher
Vigenère cipher
Task Implement a   Vigenère cypher,   both encryption and decryption. The program should handle keys and text of unequal length, and should capitalize everything and discard non-alphabetic characters. (If your program handles non-alphabetic characters in another way, make a note of it.) Related tasks   Caesar ...
#Objeck
Objeck
  bundle Default { class VigenereCipher { function : Main(args : String[]) ~ Nil { key := "VIGENERECIPHER"; ori := "Beware the Jabberwock, my son! The jaws that bite, the claws that catch!"; enc := encrypt(ori, key); IO.Console->Print("encrypt: ")->PrintLine(enc); I...
http://rosettacode.org/wiki/Visualize_a_tree
Visualize a tree
A tree structure   (i.e. a rooted, connected acyclic graph)   is often used in programming. It's often helpful to visually examine such a structure. There are many ways to represent trees to a reader, such as:   indented text   (à la unix tree command)   nested HTML tables   hierarchical GUI widgets   2D   or ...
#Wren
Wren
import "/dynamic" for Struct import "random" for Random   var Stem = Struct.create("Stem", ["str", "next"])   var SDOWN = " |" var SLAST = " `" var SNONE = " "   var rand = Random.new()   var tree // recursive tree = Fn.new { |root, head| var col = Stem.new(null, null) var tail = head while (tail) { ...
http://rosettacode.org/wiki/Walk_a_directory/Recursively
Walk a directory/Recursively
Task Walk a given directory tree and print files matching a given pattern. Note: This task is for recursive methods.   These tasks should read an entire directory tree, not a single directory. Note: Please be careful when running any code examples found here. Related task   Walk a directory/Non-recursively   ...
#Rascal
Rascal
//usage example: To list just Rascal source files, Walk(|home:///workspace/|, ".rsc"); module Walk import String; import IO; public void Walk(loc a, str pattern){ for (entry <- listEntries(a)) if (endsWith(entry, pattern)) println(entry); elseif (isDirectory(a+entry)) Walk(a+entry, pattern); }
http://rosettacode.org/wiki/Walk_a_directory/Recursively
Walk a directory/Recursively
Task Walk a given directory tree and print files matching a given pattern. Note: This task is for recursive methods.   These tasks should read an entire directory tree, not a single directory. Note: Please be careful when running any code examples found here. Related task   Walk a directory/Non-recursively   ...
#REALbasic
REALbasic
Sub printFiles(parentDir As FolderItem, pattern As String) For i As Integer = 1 To parentDir.Count If parentDir.Item(i).Directory Then printFiles(parentDir.Item(i), pattern) Else Dim rg as New RegEx Dim myMatch as RegExMatch rg.SearchPattern = pattern myMatch = rg.search(parentDi...