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/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... | #Oz | Oz | declare
class Something
feat
name %% immutable, public attribute (called a "feature")
attr
count %% mutable, private attribute
%% public method which is used as an initializer
meth init(N)
self.name = N
count := 0
end
%% public method
meth increas... |
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... | #Raku | Raku | sub MAIN ($N = 5000) {
my @points = (^$N).map: { [rand × 20 - 10, rand × 20 - 10] }
printf "%.8f between (%.5f, %.5f), (%.5f, %.5f)\n", $_[2], @($_[1]), @($_[0]) for
closest-pair(@points), closest-pair-simple(@points)
}
sub dist-squared(@a, @b) { (@a[0] - @b[0])² + (@a[1] - @b[1])² }
sub closest-pai... |
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... | #OCaml | OCaml |
(* Task : Circles of given radius through two points *)
(* Types to make code even more readable *)
type point = float * float
type radius = float
type circle = Circle of radius * point
type circ_output =
NoSolution
| OneSolution of circle
| TwoSolutions of circle * circle
| InfiniteSolutions
;;
... |
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... | #Prolog | Prolog |
:- initialization(main).
animals(['Rat', 'Ox', 'Tiger', 'Rabbit', 'Dragon', 'Snake', 'Horse', 'Goat', 'Monkey', 'Rooster', 'Dog', 'Pig']).
elements(['Wood', 'Fire', 'Earth', 'Metal', 'Water']).
animal_chars(['子','丑','寅','卯','辰','巳','午','未','申','酉','戌','亥']).
element_chars([['甲', '丙', '戊', '庚', '壬'], ['乙', '丁'... |
http://rosettacode.org/wiki/Check_that_file_exists | Check that file exists | Task
Verify that a file called input.txt and a directory called docs exist.
This should be done twice:
once for the current working directory, and
once for a file and a directory in the filesystem root.
Optional criteria (May 2015): verify it works with:
zero-length files
an ... | #Haskell | Haskell | import System.Directory (doesFileExist, doesDirectoryExist)
check :: (FilePath -> IO Bool) -> FilePath -> IO ()
check p s = do
result <- p s
putStrLn $
s ++
if result
then " does exist"
else " does not exist"
main :: IO ()
main = do
check doesFileExist "input.txt"
check doesDirectoryExis... |
http://rosettacode.org/wiki/Chaos_game | Chaos game | The Chaos Game is a method of generating the attractor of an iterated function system (IFS).
One of the best-known and simplest examples creates a fractal, using a polygon and an initial point selected at random.
Task
Play the Chaos Game using the corners of an equilateral triangle as the reference points. Add a ... | #PARI.2FGP | PARI/GP |
\\ Chaos Game (Sierpinski triangle) 2/15/17 aev
pChaosGameS3(size,lim)={
my(sz1=size\2,sz2=sz1*sqrt(3),M=matrix(size,size),x,y,xf,yf,v);
x=random(size); y=random(sz2);
for(i=1,lim, v=random(3);
if(v==0, x/=2; y/=2;);
if(v==1, x=sz1+(sz1-x)/2; y=sz2-(sz2-y)/2;);
if(v==2, x=size-(size-x)/2; y/=2;);
xf=floor(x)... |
http://rosettacode.org/wiki/Chat_server | Chat server | Task
Write a server for a minimal text based chat.
People should be able to connect via ‘telnet’, sign on with a nickname, and type messages which will then be seen by all other connected users. Arrivals and departures of chat members should generate appropriate notification messages.
| #Racket | Racket |
#lang racket
(define outs (list (current-output-port)))
(define ((tell-all who o) line)
(for ([c outs] #:unless (eq? o c)) (displayln (~a who ": " line) c)))
(define ((client i o))
(define nick (begin (display "Nick: " o) (read-line i)))
(define tell (tell-all nick o))
(let loop ([line "(joined)"])
(i... |
http://rosettacode.org/wiki/Character_codes | Character codes |
Task
Given a character value in your language, print its code (could be ASCII code, Unicode code, or whatever your language uses).
Example
The character 'a' (lowercase letter A) has a code of 97 in ASCII (as well as Unicode, as ASCII forms the beginning of Unicode).
Conversely, given a code, print out... | #Elixir | Elixir | iex(1)> code = ?a
97
iex(2)> to_string([code])
"a" |
http://rosettacode.org/wiki/Character_codes | Character codes |
Task
Given a character value in your language, print its code (could be ASCII code, Unicode code, or whatever your language uses).
Example
The character 'a' (lowercase letter A) has a code of 97 in ASCII (as well as Unicode, as ASCII forms the beginning of Unicode).
Conversely, given a code, print out... | #Emacs_Lisp | Emacs Lisp | (string-to-char "a") ;=> 97
(format "%c" 97) ;=> "a" |
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... | #PL.2FI | PL/I | (subscriptrange):
decompose: procedure options (main); /* 31 October 2013 */
declare a(*,*) float controlled;
allocate a(3,3) initial (25, 15, -5,
15, 18, 0,
-5, 0, 11);
put skip list ('Original matrix:');
put edit (a) (skip, 3 f(4));
cal... |
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, ... | #Vlang | Vlang | import time
struct Birthday {
month int
day int
}
fn (b Birthday) str() string {
return "${time.long_months[b.month-1]} $b.day"
}
fn (b Birthday) month_uniquie_in(bds []Birthday) bool {
mut count := 0
for bd in bds {
if bd.month == b.month {
count++
}
}
if count ... |
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, ... | #Wren | Wren | var Months = [
"January", "February", "March", "April", "May", "June",
"July", "August", "September", "October", "November", "December"
]
class Birthday {
construct new(month, day) {
_month = month
_day = day
}
month { _month }
day { _day }
toString { "%(Months[_month... |
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... | #OCaml | OCaml | [1; 2; 3; 4; 5] |
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
... | #R | R | print(combn(0:4, 3)) |
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 ... | #Tailspin | Tailspin |
templates foo
when <=0> do 'zero' -> !OUT::write
when <..0> do
'negative ' -> !OUT::write
-$ -> #
when <?($ mod 2 <=0>)> do 'even' -> !OUT::write
otherwise 'odd' -> !OUT::write
end foo
|
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 ... | #Tcl | Tcl | if {$foo == 3} {
puts "foo is three"
} elseif {$foo == 4} {
puts "foo is four"
} else {
puts "foo is neither three nor four"
} |
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
... | #PicoLisp | PicoLisp | (de modinv (A B)
(let (B0 B X0 0 X1 1 Q 0 T1 0)
(while (< 1 A)
(setq
Q (/ A B)
T1 B
B (% A B)
A T1
T1 X0
X0 (- X1 (* Q X0))
X1 T1 ) )
(if (lt0 X1) (+ X1 B0) X1) ) )
(de chinrem (N A)
(let P (apply * N)
... |
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
... | #Prolog | Prolog |
product(A, B, C) :- C is A*B.
pair(X, Y, X-Y).
egcd(_, 0, 1, 0) :- !.
egcd(A, B, X, Y) :-
divmod(A, B, Q, R),
egcd(B, R, S, X),
Y is S - Q*X.
modinv(A, B, X) :-
egcd(A, B, X, Y),
A*X + B*Y =:= 1.
crt_fold(A, M, P, R0, R1) :- % system of equations of (x = a) (mod m); p = M/m
modinv(P, M... |
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... | #Pascal | Pascal | {
# a class is a package (i.e. a namespace) with methods in it
package MyClass;
# a constructor is a function that returns a blessed reference
sub new {
my $class = shift;
bless {variable => 0}, $class;
# the instance object is a hashref in disguise.
# (it can be a ... |
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... | #Perl | Perl | {
# a class is a package (i.e. a namespace) with methods in it
package MyClass;
# a constructor is a function that returns a blessed reference
sub new {
my $class = shift;
bless {variable => 0}, $class;
# the instance object is a hashref in disguise.
# (it can be a ... |
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... | #REXX | REXX | /*REXX program solves the closest pair of points problem (in two dimensions). */
parse arg N LO HI seed . /*obtain optional arguments from the CL*/
if N=='' | N=="," then N= 100 /*Not specified? Then use the default.*/
if LO=='' | LO=="," then LO= 0 ... |
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... | #Oforth | Oforth | : circleCenter(x1, y1, x2, y2, r)
| d xmid ymid r1 md |
x2 x1 - sq y2 y1 - sq + sqrt -> d
x1 x2 + 2 / -> xmid
y1 y2 + 2 / -> ymid
2 r * -> r1
d 0.0 == ifTrue: [ "Infinite number of circles" . return ]
d r1 == ifTrue: [ System.Out "One circle: (" << xmid << ", " << ymid << ")" << cr return ]
... |
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... | #PureBasic | PureBasic | EnableExplicit
#BASE=4
#SPC=Chr(32)
Procedure.s ChineseZodiac(n.i)
Define cycle_year.i=n-#BASE,
stem_number.i = cycle_year%10+1,
element_number.i = Round(stem_number/2,#PB_Round_Nearest),
branch_number.i = cycle_year%12+1,
aspect_number.i = cycle_year%2+1,
index.i ... |
http://rosettacode.org/wiki/Check_that_file_exists | Check that file exists | Task
Verify that a file called input.txt and a directory called docs exist.
This should be done twice:
once for the current working directory, and
once for a file and a directory in the filesystem root.
Optional criteria (May 2015): verify it works with:
zero-length files
an ... | #hexiscript | hexiscript | println "File \"input.txt\"? " + (exists "input.txt")
println "Dir \"docs\"? " + (exists "docs/")
println "File \"/input.txt\"? " + (exists "/input.txt")
println "Dir \"/docs\"? " + (exists "/docs/") |
http://rosettacode.org/wiki/Check_that_file_exists | Check that file exists | Task
Verify that a file called input.txt and a directory called docs exist.
This should be done twice:
once for the current working directory, and
once for a file and a directory in the filesystem root.
Optional criteria (May 2015): verify it works with:
zero-length files
an ... | #HicEst | HicEst | OPEN(FIle= 'input.txt', OLD, IOStat=ios, ERror=99)
OPEN(FIle='C:\input.txt', OLD, IOStat=ios, ERror=99)
! ...
99 WRITE(Messagebox='!') 'File does not exist. Error message ', ios |
http://rosettacode.org/wiki/Chaos_game | Chaos game | The Chaos Game is a method of generating the attractor of an iterated function system (IFS).
One of the best-known and simplest examples creates a fractal, using a polygon and an initial point selected at random.
Task
Play the Chaos Game using the corners of an equilateral triangle as the reference points. Add a ... | #Pascal | Pascal |
program ChaosGame;
// FPC 3.0.2
uses
Graph, windows, math;
// Return a point on a circle defined by angle and the circles radius
// Angle 0 = Radius points to the left
// Angle 90 = Radius points upwards
Function PointOfCircle(Angle: SmallInt; Radius: integer): TPoint;
var Ia: Double;
begin
Ia:=DegToRad(-Angl... |
http://rosettacode.org/wiki/Chat_server | Chat server | Task
Write a server for a minimal text based chat.
People should be able to connect via ‘telnet’, sign on with a nickname, and type messages which will then be seen by all other connected users. Arrivals and departures of chat members should generate appropriate notification messages.
| #Raku | Raku | react {
my %connections;
whenever IO::Socket::Async.listen('localhost', 4004) -> $conn {
my $name;
$conn.print: "Please enter your name: ";
whenever $conn.Supply.lines -> $message {
if !$name {
if %connections{$message} {
$conn.print:... |
http://rosettacode.org/wiki/Character_codes | Character codes |
Task
Given a character value in your language, print its code (could be ASCII code, Unicode code, or whatever your language uses).
Example
The character 'a' (lowercase letter A) has a code of 97 in ASCII (as well as Unicode, as ASCII forms the beginning of Unicode).
Conversely, given a code, print out... | #Erlang | Erlang | 1> F = fun([X]) -> X end.
#Fun<erl_eval.6.13229925>
2> F("a").
97 |
http://rosettacode.org/wiki/Character_codes | Character codes |
Task
Given a character value in your language, print its code (could be ASCII code, Unicode code, or whatever your language uses).
Example
The character 'a' (lowercase letter A) has a code of 97 in ASCII (as well as Unicode, as ASCII forms the beginning of Unicode).
Conversely, given a code, print out... | #Euphoria | Euphoria | printf(1,"%d\n", 'a') -- prints "97"
printf(1,"%s\n", 97) -- prints "a" |
http://rosettacode.org/wiki/Cholesky_decomposition | Cholesky decomposition | Every symmetric, positive definite matrix A can be decomposed into a product of a unique lower triangular matrix L and its transpose:
A
=
L
L
T
{\displaystyle A=LL^{T}}
L
{\displaystyle L}
is called the Cholesky factor of
A
{\displaystyle A}
, and can be interpreted as a generalized square r... | #PowerShell | PowerShell |
function cholesky ($a) {
$l = @()
if ($a) {
$n = $a.count
$end = $n - 1
$l = 1..$n | foreach {$row = @(0) * $n; ,$row}
foreach ($k in 0..$end) {
$m = $k - 1
$sum = 0
if(0 -lt $k) {
foreach ($j in 0..$m) {$sum += $l[$k][$j]*$l[... |
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, ... | #zkl | zkl | dates:=T(T("May", 15), T("May", 16), T("May", 19),
T("June", 17), T("June", 18),
T("July", 14), T("July", 16),
T("August",14), T("August",15), T("August",17) );
mDs:=dates.pump(Dictionary().appendKV); // "June":(15,16,19), ...
dMs:=dates.pump(Dictionary().appendKV,"reverse"); // 15:"May", 16:"Ma... |
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... | #Oforth | Oforth | Buffer A collection of bytes
Mem A mutable collection of bytes
Interval A first value, a last value and a step.
Pair A collection of 2 elements (with key/value features).
List A collection of n elements
ListBuffer A mutable collection of n elements that can grow ... |
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
... | #Racket | Racket |
(define sublists
(match-lambda**
[(0 _) '(())]
[(_ '()) '()]
[(m (cons x xs)) (append (map (curry cons x) (sublists (- m 1) xs))
(sublists m xs))]))
(define (combinations n m)
(sublists n (range m)))
|
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 ... | #Tern | Tern | if(a > b)
println(a); |
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
... | #PureBasic | PureBasic | EnableExplicit
DisableDebugger
DataSection
LBL_n1:
Data.i 3,5,7
LBL_a1:
Data.i 2,3,2
LBL_n2:
Data.i 11,12,13
LBL_a2:
Data.i 10,4,12
LBL_n3:
Data.i 10,4,9
LBL_a3:
Data.i 11,22,19
EndDataSection
Procedure ErrorHdl()
Print(ErrorMessage())
Input()
EndProcedure
Macro PrintData(n,a)
... |
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... | #Phix | Phix | without js -- (else cffi namespaces error, classes not supported by pwa/p2js anyway)
requires ("1.0.2") -- (free up the temp used in the v.show() call)
class five nullable
private integer n = 3
function get_n()
return n
end function
procedure set_n(integer n)
this.n = n
end procedur... |
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... | #Ring | Ring |
decimals(10)
x = list(10)
y = list(10)
x[1] = 0.654682
y[1] = 0.925557
x[2] = 0.409382
y[2] = 0.619391
x[3] = 0.891663
y[3] = 0.888594
x[4] = 0.716629
y[4] = 0.996200
x[5] = 0.477721
y[5] = 0.946355
x[6] = 0.925092
y[6] = 0.818220
x[7] = 0.624291
y[7] = 0.142924
x[8] = 0.211332
y[8] = 0.221507
x[9] = 0.293786
y[9] = ... |
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... | #ooRexx | ooRexx | /*REXX pgm finds 2 circles with a specific radius given two (X,Y) points*/
a.=''
a.1=0.1234 0.9876 0.8765 0.2345 2
a.2=0.0000 2.0000 0.0000 0.0000 1
a.3=0.1234 0.9876 0.1234 0.9876 2
a.4=0.1234 0.9876 0.8765 0.2345 0.5
a.5=0.1234 0.9876 0.1234 0.9876 0
Say ' x1 y1 x2 y2 radius cir1... |
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... | #Python | Python |
# coding: utf-8
from __future__ import print_function
from datetime import datetime
pinyin = {
'甲': 'jiă',
'乙': 'yĭ',
'丙': 'bĭng',
'丁': 'dīng',
'戊': 'wù',
'己': 'jĭ',
'庚': 'gēng',
'辛': 'xīn',
'壬': 'rén',
'癸': 'gŭi',
'子': 'zĭ',
'丑': 'chŏu',
'寅': 'yín',
'卯': 'măo',
'辰': 'chén',
'巳':... |
http://rosettacode.org/wiki/Check_that_file_exists | Check that file exists | Task
Verify that a file called input.txt and a directory called docs exist.
This should be done twice:
once for the current working directory, and
once for a file and a directory in the filesystem root.
Optional criteria (May 2015): verify it works with:
zero-length files
an ... | #HolyC | HolyC | U0 FileExists(U8 *f) {
if (FileFind(f) && !IsDir(f)) {
Print("'%s' file exists.\n", f);
} else {
Print("'%s' file does not exist.\n", f);
}
}
U0 DirExists(U8 *d) {
if (IsDir(d)) {
Print("'%s' directory exists.\n", d);
} else {
Print("'%s' directory does not exist.\n", d);
}
}
FileExists(... |
http://rosettacode.org/wiki/Check_that_file_exists | Check that file exists | Task
Verify that a file called input.txt and a directory called docs exist.
This should be done twice:
once for the current working directory, and
once for a file and a directory in the filesystem root.
Optional criteria (May 2015): verify it works with:
zero-length files
an ... | #i | i | concept exists(path) {
open(path)
errors {
if error.DoesNotExist()
print(path, " does not exist!")
end
return
}
print(path, " exists!")
}
software {
exists("input.txt")
exists("/input.txt")
exists("docs")
exists("/docs")
exists("docs/Abdu'l-Bahá.txt")
} |
http://rosettacode.org/wiki/Chaos_game | Chaos game | The Chaos Game is a method of generating the attractor of an iterated function system (IFS).
One of the best-known and simplest examples creates a fractal, using a polygon and an initial point selected at random.
Task
Play the Chaos Game using the corners of an equilateral triangle as the reference points. Add a ... | #Perl | Perl | use Imager;
my $width = 1000;
my $height = 1000;
my @points = (
[ $width/2, 0],
[ 0, $height-1],
[$height-1, $height-1],
);
my $img = Imager->new(
xsize => $width,
ysize => $height,
channels => 3,
... |
http://rosettacode.org/wiki/Chat_server | Chat server | Task
Write a server for a minimal text based chat.
People should be able to connect via ‘telnet’, sign on with a nickname, and type messages which will then be seen by all other connected users. Arrivals and departures of chat members should generate appropriate notification messages.
| #Ruby | Ruby | require 'gserver'
class ChatServer < GServer
def initialize *args
super
#Keep a list for broadcasting messages
@chatters = []
#We'll need this for thread safety
@mutex = Mutex.new
end
#Send message out to everyone but sender
def broadcast message, sender = nil
#Need to use \r\n ... |
http://rosettacode.org/wiki/Character_codes | Character codes |
Task
Given a character value in your language, print its code (could be ASCII code, Unicode code, or whatever your language uses).
Example
The character 'a' (lowercase letter A) has a code of 97 in ASCII (as well as Unicode, as ASCII forms the beginning of Unicode).
Conversely, given a code, print out... | #F.23 | F# | let c = 'A'
let n = 65
printfn "%d" (int c)
printfn "%c" (char n) |
http://rosettacode.org/wiki/Character_codes | Character codes |
Task
Given a character value in your language, print its code (could be ASCII code, Unicode code, or whatever your language uses).
Example
The character 'a' (lowercase letter A) has a code of 97 in ASCII (as well as Unicode, as ASCII forms the beginning of Unicode).
Conversely, given a code, print out... | #Factor | Factor | CHAR: katakana-letter-a .
"ア" first .
12450 1string print |
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... | #Python | Python | from __future__ import print_function
from pprint import pprint
from math import sqrt
def cholesky(A):
L = [[0.0] * len(A) for _ in xrange(len(A))]
for i in xrange(len(A)):
for j in xrange(i+1):
s = sum(L[i][k] * L[j][k] for k in xrange(j))
L[i][j] = sqrt(A[i][i] - s) if (i... |
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... | #ooRexx | ooRexx |
a = .array~new(4) -- creates an array of 4 items, with all slots empty
say a~size a~items -- size is 4, but there are 0 items
a[1] = "Fred" -- assigns a value to the first item
a[5] = "Mike" -- assigns a value to the fifth slot, expanding the size
say a~size a~items -- size is now 5, with 2 items
|
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
... | #Raku | Raku | .say for combinations(5,3); |
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 ... | #TI-83_BASIC | TI-83 BASIC | If condition
statement |
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
... | #Python | Python | # Python 2.7
def chinese_remainder(n, a):
sum = 0
prod = reduce(lambda a, b: a*b, n)
for n_i, a_i in zip(n, a):
p = prod / n_i
sum += a_i * mul_inv(p, n_i) * p
return sum % prod
def mul_inv(a, b):
b0 = b
x0, x1 = 0, 1
if b == 1: return 1
while a > 1:
q = a /... |
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... | #PHL | PHL | module classes;
extern printf;
class @MyClass {
field @Integer myField { get:get_myField, set:set_myField };
new [
this.set_myField(2);
]
@Void method [
this.set_myField(this::get_myField + 1);
]
};
@Integer main [
var obj = new @MyClass;
printf("obj.myField: %i\n", obj::get_myField);
obj::method;... |
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... | #PHP | PHP | class MyClass {
public static $classVar;
public $instanceVar; // can also initialize it here
function __construct() {
$this->instanceVar = 0;
}
function someMethod() {
$this->instanceVar = 1;
self::$classVar = 3;
}
}
$myObj = new MyClass(); |
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... | #Ruby | Ruby | Point = Struct.new(:x, :y)
def distance(p1, p2)
Math.hypot(p1.x - p2.x, p1.y - p2.y)
end
def closest_bruteforce(points)
mindist, minpts = Float::MAX, []
points.combination(2) do |pi,pj|
dist = distance(pi, pj)
if dist < mindist
mindist = dist
minpts = [pi, pj]
end
end
[mindist, min... |
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... | #PARI.2FGP | PARI/GP | circ(a, b, r)={
if(a==b, return("impossible"));
my(h=(b-a)/2,t=sqrt(r^2-abs(h)^2)/abs(h)*h);
[a+h+t*I,a+h-t*I]
};
circ(0.1234 + 0.9876*I, 0.8765 + 0.2345*I, 2)
circ(0.0000 + 2.0000*I, 0.0000 + 0.0000*I, 1)
circ(0.1234 + 0.9876*I, 0.1234 + 0.9876*I, 2)
circ(0.1234 + 0.9876*I, 0.8765 + 0.2345*I, .5)
circ(0.1234 + 0... |
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... | #Racket | Racket | #lang racket
(require racket/date)
; Any CE Year that was the first of a 60-year cycle
(define base-year 1984)
(define celestial-stems '("甲" "乙" "丙" "丁" "戊" "己" "庚" "辛" "壬" "癸"))
(define terrestrial-branches '("子" "丑" "寅" "卯" "辰" "巳" "午" "未" "申" "酉" "戌" "亥"))
(define zodiac-animals
'("Rat" "Ox" "Tiger" "Rab... |
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... | #Raku | Raku | sub Chinese-zodiac ( Int $year ) {
my @heaven = <甲 jiă 乙 yĭ 丙 bĭng 丁 dīng 戊 wù 己 jĭ 庚 gēng 辛 xīn 壬 rén 癸 gŭi>.pairup;
my @earth = <子 zĭ 丑 chŏu 寅 yín 卯 măo 辰 chén 巳 sì 午 wŭ 未 wèi 申 shēn 酉 yŏu 戌 xū 亥 hài>.pairup;
my @animal = <Rat Ox Tiger Rabbit Dragon Snake Horse Goat Monkey Rooster Dog Pig>;
my @el... |
http://rosettacode.org/wiki/Check_that_file_exists | Check that file exists | Task
Verify that a file called input.txt and a directory called docs exist.
This should be done twice:
once for the current working directory, and
once for a file and a directory in the filesystem root.
Optional criteria (May 2015): verify it works with:
zero-length files
an ... | #Icon_and_Unicon | Icon and Unicon | every dir := !["./","/"] do {
write("file ", f := dir || "input.txt", if stat(f) then " exists." else " doesn't exist.")
write("directory ", f := dir || "docs", if stat(f) then " exists." else " doesn't exist.")
} |
http://rosettacode.org/wiki/Chaos_game | Chaos game | The Chaos Game is a method of generating the attractor of an iterated function system (IFS).
One of the best-known and simplest examples creates a fractal, using a polygon and an initial point selected at random.
Task
Play the Chaos Game using the corners of an equilateral triangle as the reference points. Add a ... | #Phix | Phix | --
-- demo\rosetta\Chaos_game.exw
-- ===========================
--
with javascript_semantics
include pGUI.e
Ihandle dlg, canvas
cdCanvas cddbuffer, cdcanvas
enum TRI,SQ1,SQ2,SQ3,PENT
sequence descs = {"Sierpinsky Triangle",
"Square 1",
"Square 2",
"Square 3",
... |
http://rosettacode.org/wiki/Chat_server | Chat server | Task
Write a server for a minimal text based chat.
People should be able to connect via ‘telnet’, sign on with a nickname, and type messages which will then be seen by all other connected users. Arrivals and departures of chat members should generate appropriate notification messages.
| #Rust | Rust |
use std::collections::HashMap;
use std::io;
use std::io::prelude::*;
use std::io::BufReader;
use std::net::{TcpListener, TcpStream};
use std::sync::{Arc, RwLock};
use std::thread;
type Username = String;
/// Sends a message to all clients except the sending client.
fn broadcast_message(
user: &str,
client... |
http://rosettacode.org/wiki/Character_codes | Character codes |
Task
Given a character value in your language, print its code (could be ASCII code, Unicode code, or whatever your language uses).
Example
The character 'a' (lowercase letter A) has a code of 97 in ASCII (as well as Unicode, as ASCII forms the beginning of Unicode).
Conversely, given a code, print out... | #FALSE | FALSE | 'A."
"65, |
http://rosettacode.org/wiki/Character_codes | Character codes |
Task
Given a character value in your language, print its code (could be ASCII code, Unicode code, or whatever your language uses).
Example
The character 'a' (lowercase letter A) has a code of 97 in ASCII (as well as Unicode, as ASCII forms the beginning of Unicode).
Conversely, given a code, print out... | #Fantom | Fantom | fansh> 97.toChar
a
fansh> 'a'.toInt
97 |
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... | #q | q | solve:{[A;B] $[0h>type A;B%A;inv[A] mmu B]}
ak:{[m;k] (),/:m[;k]til k:k-1}
akk:{[m;k] m[k;k:k-1]}
transpose:{$[0h=type x;flip x;enlist each x]}
mult:{[A;B]$[0h=type A;A mmu B;A*B]}
cholesky:{[A]
{[A;L;n]
l_k:solve[L;ak[A;n]];
l_kk:first over sqrt[akk[A;n] - mult[transpose l_k;l_k]];
({$[0h<type x;enlist x;x]}L... |
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... | #Oz | Oz | declare
%% Lists (immutable, recursive)
Xs = [1 2 3 4]
%% Add element at the front (cons)
Xs0 = 0|Xs
{Show {Length Xs}} %% output: 4
%% Records (immutable maps with a label)
Rec = label(1:2 symbol:3)
{Show Rec} %% output: label(2 symbol:3)
{Show Rec.1} %% output: 2
%% create a new record with an... |
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
... | #REXX | REXX | /*REXX program displays combination sets for X things taken Y at a time. */
parse arg x y $ . /*get optional arguments from the C.L. */
if x=='' | x=="," then x= 5 /*No X specified? Then use default.*/
if y=='' | y=="," then y= 3; oy= y; y= abs(y... |
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 ... | #Toka | Toka | 100 100 = [ ." True\n" ] ifTrue
100 200 = [ ." True\n" ] ifTrue |
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
... | #R | R | mul_inv <- function(a, b)
{
b0 <- b
x0 <- 0L
x1 <- 1L
if (b == 1) return(1L)
while(a > 1){
q <- as.integer(a/b)
t <- b
b <- a %% b
a <- t
t <- x0
x0 <- x1 - q*x0
x1 <- t
}
if (x1 < 0) x1 <- x1 + b0
return(x1)
}
chinese_remainder <- function(n, a)
{
len <- length(n... |
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... | #PicoLisp | PicoLisp | (class +Rectangle)
# dx dy
(dm area> () # Define a a method that calculates the rectangle's area
(* (: dx) (: dy)) )
(println # Create a rectangle, and print its area
(area> (new '(+Rectangle) 'dx 3 'dy 4)) ) |
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... | #Pop11 | Pop11 | uses objectclass;
define :class MyClass;
slot value = 1;
enddefine; |
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... | #Run_BASIC | Run BASIC | n =10 ' 10 data points input
dim x(n)
dim y(n)
pt1 = 0 ' 1st point
pt2 = 0 ' 2nd point
for i =1 to n ' read in data
read x(i)
read y(i)
next i
minDist = 1000000
for i =1 to n -1
for j =i +1... |
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... | #Perl | Perl | use strict;
sub circles {
my ($x1, $y1, $x2, $y2, $r) = @_;
return "Radius is zero" if $r == 0;
return "Coincident points gives infinite number of circles" if $x1 == $x2 and $y1 == $y2;
# delta x, delta y between points
my ($dx, $dy) = ($x2 - $x1, $y2 - $y1);
my $q = sqrt($dx**2 + $dy**2);... |
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... | #Ring | Ring |
yinyang = ["yang", "yin"]
elements = ["Wood", "Fire", "Earth", "Metal", "Water"]
animals = ["Rat", "Ox", "Tiger", "Rabbit", "Dragon", "Snake",
"Horse", "Goat", "Monkey", "Rooster", "Dog", "Pig"]
years = [1801, 1861, 1984, 2020, 2186, 76543]
output = ""
for year in years
yy = year % 2 + 1... |
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... | #Ruby | Ruby | # encoding: utf-8
pinyin = {
'甲' => 'jiă',
'乙' => 'yĭ',
'丙' => 'bĭng',
'丁' => 'dīng',
'戊' => 'wù',
'己' => 'jĭ',
'庚' => 'gēng',
'辛' => 'xīn',
'壬' => 'rén',
'癸' => 'gŭi',
'子' => 'zĭ',
'丑' => 'chŏu',
'寅' => 'yín',
'卯' => 'măo',
'辰' => 'chén',
'巳' => 'sì',
'午' => 'wŭ',
'未' => 'wèi',
... |
http://rosettacode.org/wiki/Check_that_file_exists | Check that file exists | Task
Verify that a file called input.txt and a directory called docs exist.
This should be done twice:
once for the current working directory, and
once for a file and a directory in the filesystem root.
Optional criteria (May 2015): verify it works with:
zero-length files
an ... | #IDL | IDL |
print, FILE_TEST('input.txt')
print, FILE_TEST(PATH_SEP()+'input.txt')
print, FILE_TEST('docs', /DIRECTORY)
print, FILE_TEST(PATH_SEP()+'docs', /DIRECTORY)
|
http://rosettacode.org/wiki/Check_that_file_exists | Check that file exists | Task
Verify that a file called input.txt and a directory called docs exist.
This should be done twice:
once for the current working directory, and
once for a file and a directory in the filesystem root.
Optional criteria (May 2015): verify it works with:
zero-length files
an ... | #J | J | require 'files'
fexist 'input.txt'
fexist '/input.txt'
direxist=: 2 = ftype
direxist 'docs'
direxist '/docs' |
http://rosettacode.org/wiki/Chaos_game | Chaos game | The Chaos Game is a method of generating the attractor of an iterated function system (IFS).
One of the best-known and simplest examples creates a fractal, using a polygon and an initial point selected at random.
Task
Play the Chaos Game using the corners of an equilateral triangle as the reference points. Add a ... | #Plain_English | Plain English | To run:
Start up.
Initialize our reference points.
Clear the screen to the lightest gray color.
Play the chaos game.
Refresh the screen.
Wait for the escape key.
Shut down.
To play the chaos game:
Pick a spot within 2 inches of the screen's center.
Loop.
Draw the spot.
If a counter is past 20000, exit.
Pick a referen... |
http://rosettacode.org/wiki/Chaos_game | Chaos game | The Chaos Game is a method of generating the attractor of an iterated function system (IFS).
One of the best-known and simplest examples creates a fractal, using a polygon and an initial point selected at random.
Task
Play the Chaos Game using the corners of an equilateral triangle as the reference points. Add a ... | #Processing | Processing | size(300, 260);
background(#ffffff); // white
int x = floor(random(width));
int y = floor(random(height));
int colour = #ffffff;
for (int i=0; i<30000; i++) {
int v = floor(random(3));
switch (v) {
case 0:
x = x / 2;
y = y / 2;
colour = #00ff00; // green
break;
case 1:
x = width/2 + ... |
http://rosettacode.org/wiki/Chat_server | Chat server | Task
Write a server for a minimal text based chat.
People should be able to connect via ‘telnet’, sign on with a nickname, and type messages which will then be seen by all other connected users. Arrivals and departures of chat members should generate appropriate notification messages.
| #Tcl | Tcl | package require Tcl 8.6
# Write a message to everyone except the sender of the message
proc writeEveryoneElse {sender message} {
dict for {who ch} $::cmap {
if {$who ne $sender} {
puts $ch $message
}
}
}
# How to read a line (up to 256 chars long) in a coroutine
proc cgets {ch var} {
upvar 1 $var... |
http://rosettacode.org/wiki/Character_codes | Character codes |
Task
Given a character value in your language, print its code (could be ASCII code, Unicode code, or whatever your language uses).
Example
The character 'a' (lowercase letter A) has a code of 97 in ASCII (as well as Unicode, as ASCII forms the beginning of Unicode).
Conversely, given a code, print out... | #Forth | Forth | char a
dup . \ 97
emit \ a |
http://rosettacode.org/wiki/Character_codes | Character codes |
Task
Given a character value in your language, print its code (could be ASCII code, Unicode code, or whatever your language uses).
Example
The character 'a' (lowercase letter A) has a code of 97 in ASCII (as well as Unicode, as ASCII forms the beginning of Unicode).
Conversely, given a code, print out... | #Fortran | Fortran | WRITE(*,*) ACHAR(97), IACHAR("a")
WRITE(*,*) CHAR(97), ICHAR("a") |
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... | #R | R | t(chol(matrix(c(25, 15, -5, 15, 18, 0, -5, 0, 11), nrow=3, ncol=3)))
# [,1] [,2] [,3]
# [1,] 5 0 0
# [2,] 3 3 0
# [3,] -1 1 3
t(chol(matrix(c(18, 22, 54, 42, 22, 70, 86, 62, 54, 86, 174, 134, 42, 62, 134, 106), nrow=4, ncol=4)))
# [,1] [,2] [,3] [,4]
# [1,] 4.2426... |
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... | #Racket | Racket |
#lang racket
(require math)
(define (cholesky A)
(define mref matrix-ref)
(define n (matrix-num-rows A))
(define L (for/vector ([_ n]) (for/vector ([_ n]) 0)))
(define (set L i j x) (vector-set! (vector-ref L i) j x))
(define (ref L i j) (vector-ref (vector-ref L i) j))
(for* ([i n] [k n])
(set L i ... |
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... | #PARI.2FGP | PARI/GP | v = vector(0);
v = [];
cv = vectorv(0);
cv = []~;
m = matrix(1,1);
s = Set(v);
l = List(v);
vs = vectorsmall(0);
M = Map() |
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
... | #Ring | Ring |
# Project : Combinations
n = 5
k = 3
temp = []
comb = []
num = com(n, k)
while true
temp = []
for n = 1 to 3
tm = random(4) + 1
add(temp, tm)
next
bool1 = (temp[1] = temp[2]) and (temp[1] = temp[3]) and (temp[2] = temp[3])
bool2 = (temp[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 ... | #TorqueScript | TorqueScript | // numbers and objects
if(%num == 1)
{
foo();
}
else if(%obj == MyObject.getID())
{
bar();
}
else
{
deusEx();
}
// strings
if(%str $= "Hello World")
{
foo();
}
else if(%str $= "Bye World")
{
bar();
}
else
{
deusEx();
} |
http://rosettacode.org/wiki/Chinese_remainder_theorem | Chinese remainder theorem | Suppose
n
1
{\displaystyle n_{1}}
,
n
2
{\displaystyle n_{2}}
,
…
{\displaystyle \ldots }
,
n
k
{\displaystyle n_{k}}
are positive integers that are pairwise co-prime.
Then, for any given sequence of integers
a
1
{\displaystyle a_{1}}
,
a
2
... | #Racket | Racket | #lang racket
(require (only-in math/number-theory solve-chinese))
(define as '(2 3 2))
(define ns '(3 5 7))
(solve-chinese as ns) |
http://rosettacode.org/wiki/Chinese_remainder_theorem | Chinese remainder theorem | Suppose
n
1
{\displaystyle n_{1}}
,
n
2
{\displaystyle n_{2}}
,
…
{\displaystyle \ldots }
,
n
k
{\displaystyle n_{k}}
are positive integers that are pairwise co-prime.
Then, for any given sequence of integers
a
1
{\displaystyle a_{1}}
,
a
2
... | #Raku | Raku | # returns x where (a * x) % b == 1
sub mul-inv($a is copy, $b is copy) {
return 1 if $b == 1;
my ($b0, @x) = $b, 0, 1;
($a, $b, @x) = (
$b,
$a % $b,
@x[1] - ($a div $b)*@x[0],
@x[0]
) while $a > 1;
@x[1] += $b0 if @x[1] < 0;
return @x[1];
}
sub chinese-remainder(*@n) {
my \N = [*] @n;
... |
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... | #Portugol | Portugol |
programa {
inclua biblioteca Objetos --> obj
// "constructor" returns address of object
funcao inteiro my_class_new(inteiro value) {
inteiro this = obj.criar_objeto()
obj.atribuir_propriedade(this, "variable", value) // add property to object
retorne this
}
// "method" ... |
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... | #PowerShell | PowerShell |
Add-Type -Language CSharp -TypeDefinition @'
public class MyClass
{
public MyClass()
{
}
public void SomeMethod()
{
}
private int _variable;
public int Variable
{
get { return _variable; }
set { _variable = value; }
}
public static void Main()
{
... |
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... | #Rust | Rust |
//! We interpret complex numbers as points in the Cartesian plane, here. We also use the
//! [sweepline/plane sweep closest pairs algorithm][algorithm] instead of the divide-and-conquer
//! algorithm, since it's (arguably) easier to implement, and an efficient implementation does not
//! require use of unsafe.
//!
//... |
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... | #Phix | Phix | with javascript_semantics
constant tests = {{0.1234, 0.9876, 0.8765, 0.2345, 2.0},
{0.0000, 2.0000, 0.0000, 0.0000, 1.0},
{0.1234, 0.9876, 0.1234, 0.9876, 2.0},
{0.1234, 0.9876, 0.8765, 0.2345, 0.5},
{0.1234, 0.9876, 0.1234, 0.9876, 0.0}}
for i=1 t... |
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... | #Rust | Rust | fn chinese_zodiac(year: usize) -> String {
static ANIMALS: [&str; 12] = [
"Rat", "Ox", "Tiger", "Rabbit", "Dragon", "Snake",
"Horse", "Goat", "Monkey", "Rooster", "Dog", "Pig",
];
static ASPECTS: [&str; 2] = ["Yang", "Yin"];
static ELEMENTS: [&str; 5] = ["Wood", "Fire", "Earth", "Metal",... |
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... | #Scala | Scala | object Zodiac extends App {
val years = Seq(1935, 1938, 1968, 1972, 1976, 1984, 1985, 2017, 2018)
private def animals =
Seq("Rat",
"Ox",
"Tiger",
"Rabbit",
"Dragon",
"Snake",
"Horse",
"Goat",
"Monkey",
"Rooster",
"Dog",
"Pig")
private def a... |
http://rosettacode.org/wiki/Check_that_file_exists | Check that file exists | Task
Verify that a file called input.txt and a directory called docs exist.
This should be done twice:
once for the current working directory, and
once for a file and a directory in the filesystem root.
Optional criteria (May 2015): verify it works with:
zero-length files
an ... | #Java | Java | import java.io.File;
public class FileExistsTest {
public static boolean isFileExists(String filename) {
boolean exists = new File(filename).exists();
return exists;
}
public static void test(String type, String filename) {
System.out.println("The following " + type + " called " + filename... |
http://rosettacode.org/wiki/Chaos_game | Chaos game | The Chaos Game is a method of generating the attractor of an iterated function system (IFS).
One of the best-known and simplest examples creates a fractal, using a polygon and an initial point selected at random.
Task
Play the Chaos Game using the corners of an equilateral triangle as the reference points. Add a ... | #Python | Python |
import argparse
import random
import shapely.geometry as geometry
import numpy as np
import matplotlib.pyplot as plt
import matplotlib.animation as animation
def main(args):
# Styles
plt.style.use("ggplot")
# Creating figure
fig = plt.figure()
line, = plt.plot([], [], ".")
# Limit axes... |
http://rosettacode.org/wiki/Chat_server | Chat server | Task
Write a server for a minimal text based chat.
People should be able to connect via ‘telnet’, sign on with a nickname, and type messages which will then be seen by all other connected users. Arrivals and departures of chat members should generate appropriate notification messages.
| #Visual_Basic_.NET | Visual Basic .NET | Imports System.Net.Sockets
Imports System.Text
Imports System.Threading
Module Module1
Class State
Private ReadOnly client As TcpClient
Private ReadOnly sb As New StringBuilder
Public Sub New(name As String, client As TcpClient)
Me.Name = name
Me.client = client... |
http://rosettacode.org/wiki/Character_codes | Character codes |
Task
Given a character value in your language, print its code (could be ASCII code, Unicode code, or whatever your language uses).
Example
The character 'a' (lowercase letter A) has a code of 97 in ASCII (as well as Unicode, as ASCII forms the beginning of Unicode).
Conversely, given a code, print out... | #Free_Pascal | Free Pascal |
' FreeBASIC v1.05.0 win64
Print "a - > "; Asc("a")
Print "98 -> "; Chr(98)
Print
Print "Press any key to exit the program"
Sleep
End
|
http://rosettacode.org/wiki/Character_codes | Character codes |
Task
Given a character value in your language, print its code (could be ASCII code, Unicode code, or whatever your language uses).
Example
The character 'a' (lowercase letter A) has a code of 97 in ASCII (as well as Unicode, as ASCII forms the beginning of Unicode).
Conversely, given a code, print out... | #FreeBASIC | FreeBASIC |
' FreeBASIC v1.05.0 win64
Print "a - > "; Asc("a")
Print "98 -> "; Chr(98)
Print
Print "Press any key to exit the program"
Sleep
End
|
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... | #Raku | Raku | sub cholesky(@A) {
my @L = @A »*» 0;
for ^@A -> $i {
for 0..$i -> $j {
@L[$i][$j] = ($i == $j ?? &sqrt !! 1/@L[$j][$j] * * )(
@A[$i][$j] - [+] (@L[$i;*] Z* @L[$j;*])[^$j]
);
}
}
return @L;
}
.say for cholesky [
[25],
[15, 18],
[-5, 0, 11],
];
.say for cholesky [
[18, 22,... |
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... | #Pascal | Pascal | var
MyArray: array[1..5] of real;
begin
MyArray[1] := 4.35;
end; |
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
... | #Ruby | Ruby | def comb(m, n)
(0...n).to_a.combination(m).to_a
end
comb(3, 5) # => [[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]] |
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