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 | response_seed stringclasses 1
value | instruction_seed stringlengths 27 14.4k | _source stringclasses 1
value |
|---|---|---|---|---|---|---|---|---|
http://rosettacode.org/wiki/Queue/Usage | Queue/Usage |
Data Structure
This illustrates a data structure, a means of storing data within a program.
You may see other such structures in the Data Structures category.
Illustration of FIFO behavior
Task
Create a queue data structure and demonstrate its operations.
(For implementations of queues, see the FIFO task.)
Ope... | #Lua | Lua | q = Queue.new()
Queue.push( q, 5 )
Queue.push( q, "abc" )
while not Queue.empty( q ) do
print( Queue.pop( q ) )
end | Give a code snippet in #Lua
Data Structure
This illustrates a data structure, a means of storing data within a program.
You may see other such structures in the Data Structures category.
Illustration of FIFO behavior
Task
Create a queue data structure and demonstrate its operations.
(For implementations of queue... | christopher/rosetta-code | |
http://rosettacode.org/wiki/File_size | File size | Verify the size of a file called input.txt for a file in the current working directory, and another one in the file system root.
| #Liberty_BASIC | Liberty BASIC | 'input.txt in current directory
OPEN DefaultDir$ + "/input.txt" FOR input AS #m
PRINT "File size: "; lof(#m)
CLOSE #m
'input.txt in root
OPEN "c:/input.txt" FOR input AS #m
PRINT "File size: "; lof(#m)
CLOSE #m | Give a code snippet in #Liberty_BASIC
Verify the size of a file called input.txt for a file in the current working directory, and another one in the file system root.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Knight%27s_tour | Knight's tour |
Task
Problem: you have a standard 8x8 chessboard, empty but for a single knight on some square. Your task is to emit a series of legal knight moves that result in the knight visiting every square on the chessboard exactly once. Note that it is not a requirement that the tour be "closed"; that is, the knight need not e... | #R | R | #!/usr/bin/Rscript
# M x N Chess Board.
M = 8; N = 8; board = matrix(0, nrow = M, ncol = N)
# Get/Set value on a board position.
getboard = function (position) { board[position[1], position[2]] }
setboard = function (position, x) { board[position[1], position[2]] <<- x }
# (Relative) Hops of a Knight.
hops = c... | Give a code snippet in #R
Task
Problem: you have a standard 8x8 chessboard, empty but for a single knight on some square. Your task is to emit a series of legal knight moves that result in the knight visiting every square on the chessboard exactly once. Note that it is not a requirement that the tour be "closed"; tha... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sorting_algorithms/Insertion_sort | Sorting algorithms/Insertion sort |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
... | #ActionScript | ActionScript | function insertionSort(array:Array)
{
for(var i:int = 1; i < array.length;i++)
{
var value = array[i];
var j:int = i-1;
while(j >= 0 && array[j] > value)
{
array[j+1] = array[j];
j--;
}
array[j+1] = value;
}
return array;
} | Give a code snippet in #ActionScript
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Q... | christopher/rosetta-code | |
http://rosettacode.org/wiki/MD5 | MD5 | Task
Encode a string using an MD5 algorithm. The algorithm can be found on Wikipedia.
Optionally, validate your implementation by running all of the test values in IETF RFC (1321) for MD5.
Additionally, RFC 1321 provides more precise information on the algorithm than the Wikipedia article.
Warning:... | #PicoLisp | PicoLisp | (let Str "The quick brown fox jumped over the lazy dog's back"
(pack
(mapcar '((B) (pad 2 (hex B)))
(native "libcrypto.so" "MD5" '(B . 16) Str (length Str) '(NIL (16))) ) ) ) | Give a code snippet in #PicoLisp
Task
Encode a string using an MD5 algorithm. The algorithm can be found on Wikipedia.
Optionally, validate your implementation by running all of the test values in IETF RFC (1321) for MD5.
Additionally, RFC 1321 provides more precise information on the algorithm than t... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Exceptions | Exceptions | Control Structures
These are examples of control structures. You may also be interested in:
Conditional structures
Exceptions
Flow-control structures
Loops
This task is to give an example of an exception handling routine
and to "throw" a new exception.
Related task
Exceptions Through Nested Calls
| #MATLAB | MATLAB | >> error 'Help'
??? Help | Give a code snippet in #MATLAB
Control Structures
These are examples of control structures. You may also be interested in:
Conditional structures
Exceptions
Flow-control structures
Loops
This task is to give an example of an exception handling routine
and to "throw" a new exception.
Related task
Exception... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Kosaraju | Kosaraju |
This page uses content from Wikipedia. The original article was at Graph. 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)
Kosaraju's algorithm (also known as the Kosaraju–Sharir algorithm) is a lin... | #Python | Python | def kosaraju(g):
class nonlocal: pass
# 1. For each vertex u of the graph, mark u as unvisited. Let l be empty.
size = len(g)
vis = [False]*size # vertexes that have been visited
l = [0]*size
nonlocal.x = size
t = [[]]*size # transpose graph
def visit(u):
if not vis[u]:
... | Give a code snippet in #Python
This page uses content from Wikipedia. The original article was at Graph. 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)
Kosaraju's algorithm (also known as the Kos... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Text_processing/2 | Text processing/2 | The following task concerns data that came from a pollution monitoring station with twenty-four instruments monitoring twenty-four aspects of pollution in the air. Periodically a record is added to the file, each record being a line of 49 fields separated by white-space, which can be one or more space or tab characters... | #R | R | # Read in data from file
dfr <- read.delim("d:/readings.txt", colClasses=c("character", rep(c("numeric", "integer"), 24)))
dates <- strptime(dfr[,1], "%Y-%m-%d")
# Any bad values?
dfr[which(is.na(dfr))]
# Any duplicated dates
dates[duplicated(dates)]
# Number of rows with no bad values
flags <- as.matrix(dfr[,seq... | Give a code snippet in #R
The following task concerns data that came from a pollution monitoring station with twenty-four instruments monitoring twenty-four aspects of pollution in the air. Periodically a record is added to the file, each record being a line of 49 fields separated by white-space, which can be one or m... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Inheritance/Multiple | Inheritance/Multiple | Multiple inheritance allows to specify that one class is a subclass of several other classes.
Some languages allow multiple inheritance for arbitrary classes, others restrict it to interfaces, some don't allow it at all.
Task
Write two classes (or interfaces) Camera and MobilePhone, then write a class Camer... | #Ada | Ada | package Multiple_Interfaces is
type Camera is tagged null record;
type Mobile_Phone is limited Interface;
type Camera_Phone is new Camera and Mobile_Phone with null record;
end Multiple_Interfaces; | Give a code snippet in #Ada
Multiple inheritance allows to specify that one class is a subclass of several other classes.
Some languages allow multiple inheritance for arbitrary classes, others restrict it to interfaces, some don't allow it at all.
Task
Write two classes (or interfaces) Camera and MobilePhon... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Cantor_set | Cantor set | Task
Draw a Cantor set.
See details at this Wikipedia webpage: Cantor set
| #Java | Java | public class App {
private static final int WIDTH = 81;
private static final int HEIGHT = 5;
private static char[][] lines;
static {
lines = new char[HEIGHT][WIDTH];
for (int i = 0; i < HEIGHT; i++) {
for (int j = 0; j < WIDTH; j++) {
lines[i][j] = '*';
... | Give a code snippet in #Java
Task
Draw a Cantor set.
See details at this Wikipedia webpage: Cantor set
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Abbreviations,_easy | Abbreviations, easy | This task is an easier (to code) variant of the Rosetta Code task: Abbreviations, simple.
For this task, the following command table will be used:
Add ALTer BAckup Bottom CAppend Change SCHANGE CInsert CLAst COMPress COpy
COUnt COVerlay CURsor DELete CDelete Down DUPlicate Xedit EXPand EXTract Find
... | #Vlang | Vlang | import encoding.utf8
fn validate(commands []string, words []string, min_len []int) []string {
mut results := []string{}
if words.len == 0 {
return results
}
for word in words {
mut match_found := false
wlen := word.len
for i, command in commands {
if min_len... | Give a code snippet in #Vlang
This task is an easier (to code) variant of the Rosetta Code task: Abbreviations, simple.
For this task, the following command table will be used:
Add ALTer BAckup Bottom CAppend Change SCHANGE CInsert CLAst COMPress COpy
COUnt COVerlay CURsor DELete CDelete Down DUPli... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Long_literals,_with_continuations | Long literals, with continuations | This task is about writing a computer program that has long literals (character
literals that may require specifying the words/tokens on more than one (source)
line, either with continuations or some other method, such as abutments or
concatenations (or some other mechanisms).
The literal is to be in the form ... | #Go | Go | package main
import (
"fmt"
"regexp"
"strings"
)
// Uses a 'raw string literal' which is a character sequence enclosed in back quotes.
// Within the quotes any character (including new line) may appear except
// back quotes themselves.
var elements = `
hydrogen helium lithium berylli... | Give a code snippet in #Go
This task is about writing a computer program that has long literals (character
literals that may require specifying the words/tokens on more than one (source)
line, either with continuations or some other method, such as abutments or
concatenations (or some other mechanisms).
The l... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sorting_algorithms/Patience_sort | Sorting algorithms/Patience sort |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
... | #Perl | Perl | sub patience_sort {
my @s = [shift];
for my $card (@_) {
my @t = grep { $_->[-1] > $card } @s;
if (@t) { push @{shift(@t)}, $card }
else { push @s, [$card] }
}
my @u;
while (my @v = grep @$_, @s) {
my $value = (my $min = shift @v)->[-1];
for (@v) {
($min, $value) =
($_, $_->[-1]) if $... | Give a code snippet in #Perl
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sor... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Caesar_cipher | Caesar cipher |
Task
Implement a Caesar cipher, both encoding and decoding.
The key is an integer from 1 to 25.
This cipher rotates (either towards left or right) the letters of the alphabet (A to Z).
The encoding replaces each letter with the 1st to 25th next letter in the alphabet (wrapping Z to A).
So key 2 encrypts "HI" to... | #PicoLisp | PicoLisp | (setq *Letters (apply circ (mapcar char (range 65 90))))
(de caesar (Str Key)
(pack
(mapcar '((C) (cadr (nth (member C *Letters) Key)))
(chop (uppc Str)) ) ) ) | Give a code snippet in #PicoLisp
Task
Implement a Caesar cipher, both encoding and decoding.
The key is an integer from 1 to 25.
This cipher rotates (either towards left or right) the letters of the alphabet (A to Z).
The encoding replaces each letter with the 1st to 25th next letter in the alphabet (wrapping Z... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Leap_year | Leap year | Task
Determine whether a given year is a leap year in the Gregorian calendar.
See also
Leap year (wiki)
| #JavaScript | JavaScript | var isLeapYear = function (year) { return (year % 100 === 0) ? (year % 400 === 0) : (year % 4 === 0); }; | Give a code snippet in #JavaScript
Task
Determine whether a given year is a leap year in the Gregorian calendar.
See also
Leap year (wiki)
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Sum_and_product_of_an_array | Sum and product of an array | Task
Compute the sum and product of an array of integers.
| #Gambas | Gambas | Public Sub Main()
Dim iList As Integer[] = [1, 2, 3, 4, 5]
Dim iSum, iCount As Integer
Dim iPrd As Integer = 1
For iCount = 0 To iList.Max
iSum += iList[iCount]
iPrd *= iList[iCount]
Next
Print "The Sum =\t" & iSum
Print "The Product =\t" & iPrd
End | Give a code snippet in #Gambas
Task
Compute the sum and product of an array of integers.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Roman_numerals/Encode | Roman numerals/Encode | Task
Create a function taking a positive integer as its parameter and returning a string containing the Roman numeral representation of that integer. Modern Roman numerals are written by expressing each digit separately, starting with the left most digit and skipping any digit with a value of zero.
In Roman numeral... | #PowerBASIC | PowerBASIC | FUNCTION toRoman(value AS INTEGER) AS STRING
DIM arabic(0 TO 12) AS INTEGER
DIM roman(0 TO 12) AS STRING
ARRAY ASSIGN arabic() = 1000, 900, 500, 400, 100, 90, 50, 40, 10, 9, 5, 4, 1
ARRAY ASSIGN roman() = "M", "CM", "D", "CD", "C", "XC", "L", "XL", "X", "IX", "V", "IV", "I"
DIM i AS INTEGER
DI... | Give a code snippet in #PowerBASIC
Task
Create a function taking a positive integer as its parameter and returning a string containing the Roman numeral representation of that integer. Modern Roman numerals are written by expressing each digit separately, starting with the left most digit and skipping any digit with ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Hilbert_curve | Hilbert curve |
Task
Produce a graphical or ASCII-art representation of a Hilbert curve of at least order 3.
| #zkl | zkl | hilbert(6) : turtle(_);
fcn hilbert(n){ // Lindenmayer system --> Data of As & Bs
var [const] A="-BF+AFA+FB-", B="+AF-BFB-FA+";
buf1,buf2 := Data(Void,"A").howza(3), Data().howza(3); // characters
do(n){
buf1.pump(buf2.clear(),fcn(c){ if(c=="A") A else if(c=="B") B else c });
t:=buf1; buf1=buf2;... | Give a code snippet in #zkl
Task
Produce a graphical or ASCII-art representation of a Hilbert curve of at least order 3.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Tokenize_a_string_with_escaping | Tokenize a string with escaping | Task[edit]
Write a function or program that can split a string at each non-escaped occurrence of a separator character.
It should accept three input parameters:
The string
The separator character
The escape character
It should output a list of strings.
Details
Rules for splitting:
The fields that were s... | #Ring | Ring |
tokenize("one^|uno||three^^^^|four^^^|^cuatro|", "|", "^")
func tokenize(src, sep, esc)
field = 1
escaping = false
see "" + field + " "
for i = 1 to len(src)
char = substr(src, i, 1)
if escaping
see char
escaping = false
else
switch char
on sep
see n... | Give a code snippet in #Ring
Task[edit]
Write a function or program that can split a string at each non-escaped occurrence of a separator character.
It should accept three input parameters:
The string
The separator character
The escape character
It should output a list of strings.
Details
Rules for split... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Increasing_gaps_between_consecutive_Niven_numbers | Increasing gaps between consecutive Niven numbers | Note: Niven numbers are also called Harshad numbers.
They are also called multidigital numbers.
Niven numbers are positive integers which are evenly divisible by the sum of its
digits (expressed in base ten).
Evenly divisible means divisible with no remainder.
Task
find the gap (differen... | #zkl | zkl | harshadW:=[1..].tweak(fcn(n){ if(n%(n.split().sum(0))) Void.Skip else n });
harshadW:=Walker.zero().tweak(fcn(go){ // faster than one liner, fewer calls
foreach h in ([go.value..]){ // spin
s,t := 0,h; while(t){ s+=t%10; t/=10 } // sum of digits
if(0 == h%s){ go.set(h+1); return(h) }
}
}.fp(Ref(1)... | Give a code snippet in #zkl
Note: Niven numbers are also called Harshad numbers.
They are also called multidigital numbers.
Niven numbers are positive integers which are evenly divisible by the sum of its
digits (expressed in base ten).
Evenly divisible means divisible with no remainder.
Ta... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Averages/Arithmetic_mean | Averages/Arithmetic mean | Task[edit]
Write a program to find the mean (arithmetic average) of a numeric vector.
In case of a zero-length input, since the mean of an empty set of numbers is ill-defined, the program may choose to behave in any way it deems appropriate, though if the programming language has an established convention for conveyin... | #dc | dc | 1 2 3 5 7 zsn1k[+z1<+]ds+xln/p
3.6 | Give a code snippet in #dc
Task[edit]
Write a program to find the mean (arithmetic average) of a numeric vector.
In case of a zero-length input, since the mean of an empty set of numbers is ill-defined, the program may choose to behave in any way it deems appropriate, though if the programming language has an establi... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Miller%E2%80%93Rabin_primality_test | Miller–Rabin primality test |
This page uses content from Wikipedia. The original article was at Miller–Rabin primality test. 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)
The Miller–Rabin primality test or Rabin–Miller prima... | #Erlang | Erlang |
-module(miller_rabin).
-export([is_prime/1, power/2]).
is_prime(1) -> false;
is_prime(2) -> true;
is_prime(3) -> true;
is_prime(N) when N > 3, ((N rem 2) == 0) -> false;
is_prime(N) when ((N rem 2) ==1), N < 341550071728321 ->
is_mr_prime(N, proving_bases(N));
is_prime(N) when ((N rem 2) == 1) ->
is_mr_pri... | Give a code snippet in #Erlang
This page uses content from Wikipedia. The original article was at Miller–Rabin primality test. 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)
The Miller–Rabin prim... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Inverted_syntax | Inverted syntax | Inverted syntax with conditional expressions
In traditional syntax conditional expressions are usually shown before the action within a statement or code block:
IF raining=true THEN needumbrella=true
In inverted syntax, the action is listed before the conditional expression in the statement or code block:
needumb... | #CoffeeScript | CoffeeScript | alert "hello" if true
alert "hello again" unless false # the same as the above; unless is a negated if.
idx = 0
arr = (++idx while idx < 10) # arr is [1,2,3,4,5,6,7,8,9,10]
idx = 0
arr = (++idx until idx is 10) # same as above; until is an inverted while. | Give a code snippet in #CoffeeScript
Inverted syntax with conditional expressions
In traditional syntax conditional expressions are usually shown before the action within a statement or code block:
IF raining=true THEN needumbrella=true
In inverted syntax, the action is listed before the conditional expression in ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Population_count | Population count | Population count
You are encouraged to solve this task according to the task description, using any language you may know.
The population count is the number of 1s (ones) in the binary representation of a non-negative integer.
Population count is also known as:
pop count
popcount
sideways sum
... | #11l | 11l | F popcount(n)
R bin(n).count(‘1’)
print((0.<30).map(i -> popcount(Int64(3) ^ i)))
[Int] evil, odious
V i = 0
L evil.len < 30 | odious.len < 30
V p = popcount(i)
I (p % 2) != 0
odious.append(i)
E
evil.append(i)
i++
print(evil[0.<30])
print(odious[0.<30]) | Give a code snippet in #11l
Population count
You are encouraged to solve this task according to the task description, using any language you may know.
The population count is the number of 1s (ones) in the binary representation of a non-negative integer.
Population count is also known as:
pop count
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/First-class_functions/Use_numbers_analogously | First-class functions/Use numbers analogously | In First-class functions, a language is showing how its manipulation of functions is similar to its manipulation of other types.
This tasks aim is to compare and contrast a language's implementation of first class functions, with its normal handling of numbers.
Write a program to create an ordered collection of a m... | #Raku | Raku | sub multiplied ($g, $f) { return { $g * $f * $^x } }
my $x = 2.0;
my $xi = 0.5;
my $y = 4.0;
my $yi = 0.25;
my $z = $x + $y;
my $zi = 1.0 / ( $x + $y );
my @numbers = $x, $y, $z;
my @inverses = $xi, $yi, $zi;
for flat @numbers Z @inverses { say multiplied($^g, $^f)(.5) } | Give a code snippet in #Raku
In First-class functions, a language is showing how its manipulation of functions is similar to its manipulation of other types.
This tasks aim is to compare and contrast a language's implementation of first class functions, with its normal handling of numbers.
Write a program to creat... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Leap_year | Leap year | Task
Determine whether a given year is a leap year in the Gregorian calendar.
See also
Leap year (wiki)
| #Liberty_BASIC | Liberty BASIC | if leap(1996)then
print "leap"
else
print "ordinary"
end if
wait
function leap(n)
leap=date$("2/29/";n)
end function | Give a code snippet in #Liberty_BASIC
Task
Determine whether a given year is a leap year in the Gregorian calendar.
See also
Leap year (wiki)
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Zero_to_the_zero_power | Zero to the zero power | Some computer programming languages are not exactly consistent (with other computer programming languages)
when raising zero to the zeroth power: 00
Task
Show the results of raising zero to the zeroth power.
If your computer language objects to 0**0 or 0^0 at compile time, ... | #Commodore_BASIC | Commodore BASIC | ready.
print 0↑0
1
ready.
█ | Give a code snippet in #Commodore_BASIC
Some computer programming languages are not exactly consistent (with other computer programming languages)
when raising zero to the zeroth power: 00
Task
Show the results of raising zero to the zeroth power.
If your computer language objects to 0**... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Angle_difference_between_two_bearings | Angle difference between two bearings | Finding the angle between two bearings is often confusing.[1]
Task
Find the angle which is the result of the subtraction b2 - b1, where b1 and b2 are the bearings.
Input bearings are expressed in the range -180 to +180 degrees.
The result is also expressed in the range -180 to +180 degrees.
... | #NewLISP | NewLISP |
#!/usr/bin/env newlisp
(define (bearing- bearing heading) (sub (mod (add (mod (sub bearing heading) 360.0) 540.0) 360.0) 180.0))
(bearing- 20 45)
(bearing- -45 45)
(bearing- -85 90)
(bearing- -95 90)
(bearing- -45 125)
(bearing- -45 145)
(bearing- 29.4803 -88.6381)
(bearing- -78.3251 -159.036)
(bearing- -70099.7423... | Give a code snippet in #NewLISP
Finding the angle between two bearings is often confusing.[1]
Task
Find the angle which is the result of the subtraction b2 - b1, where b1 and b2 are the bearings.
Input bearings are expressed in the range -180 to +180 degrees.
The result is also expressed in the range ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Anagrams | Anagrams | When two or more words are composed of the same characters, but in a different order, they are called anagrams.
Task[edit]
Using the word list at http://wiki.puzzlers.org/pub/wordlists/unixdict.txt,
find the sets of words that share the same characters that contain the most words in them.
Related tasks
Word plays
... | #Mathematica.2FWolfram_Language | Mathematica/Wolfram Language | list=Import["http://wiki.puzzlers.org/pub/wordlists/unixdict.txt","Lines"];
text={#,StringJoin@@Sort[Characters[#]]}&/@list;
text=SortBy[text,#[[2]]&];
splits=Split[text,#1[[2]]==#2[[2]]&][[All,All,1]];
maxlen=Max[Length/@splits];
Select[splits,Length[#]==maxlen&] | Give a code snippet in #Mathematica.2FWolfram_Language
When two or more words are composed of the same characters, but in a different order, they are called anagrams.
Task[edit]
Using the word list at http://wiki.puzzlers.org/pub/wordlists/unixdict.txt,
find the sets of words that share the same characters that co... | christopher/rosetta-code | |
http://rosettacode.org/wiki/One_of_n_lines_in_a_file | One of n lines in a file | A method of choosing a line randomly from a file:
Without reading the file more than once
When substantial parts of the file cannot be held in memory
Without knowing how many lines are in the file
Is to:
keep the first line of the file as a possible choice, then
Read the second line of the file if possible and m... | #C.2B.2B | C++ | #include <random>
#include <iostream>
#include <iterator>
#include <algorithm>
using namespace std;
mt19937 engine; //mersenne twister
unsigned int one_of_n(unsigned int n) {
unsigned int choice;
for(unsigned int i = 0; i < n; ++i) {
uniform_int_distribution<unsigned int> distribution(0, i);
if(!distribution(... | Give a code snippet in #C.2B.2B
A method of choosing a line randomly from a file:
Without reading the file more than once
When substantial parts of the file cannot be held in memory
Without knowing how many lines are in the file
Is to:
keep the first line of the file as a possible choice, then
Read the second l... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Rock-paper-scissors | Rock-paper-scissors | Task
Implement the classic children's game Rock-paper-scissors, as well as a simple predictive AI (artificial intelligence) player.
Rock Paper Scissors is a two player game.
Each player chooses one of rock, paper or scissors, without knowing the other player's choice.
The winner is decided by a set of rules:
... | #Factor | Factor | USING: combinators formatting io kernel math math.ranges qw
random sequences ;
IN: rosetta-code.rock-paper-scissors
CONSTANT: thing qw{ rock paper scissors }
CONSTANT: msg { "I win." "Tie!" "You win." }
: ai-choice ( r p s -- n )
3dup + + nip [1,b] random {
{ [ 3dup nip >= ] [ 3drop 1 ] }
{ [ 3d... | Give a code snippet in #Factor
Task
Implement the classic children's game Rock-paper-scissors, as well as a simple predictive AI (artificial intelligence) player.
Rock Paper Scissors is a two player game.
Each player chooses one of rock, paper or scissors, without knowing the other player's choice.
The winne... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Send_an_unknown_method_call | Send an unknown method call | Task
Invoke an object method where the name of the method to be invoked can be generated at run time.
Related tasks
Respond to an unknown method call.
Runtime evaluation
| #Swift | Swift | import Foundation
class MyUglyClass: NSObject {
@objc
func myUglyFunction() {
print("called myUglyFunction")
}
}
let someObject: NSObject = MyUglyClass()
someObject.perform(NSSelectorFromString("myUglyFunction")) | Give a code snippet in #Swift
Task
Invoke an object method where the name of the method to be invoked can be generated at run time.
Related tasks
Respond to an unknown method call.
Runtime evaluation
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Spinning_rod_animation/Text | Spinning rod animation/Text | Task
An animation with the following frames in the following order (if certain characters aren't available or can't be used correctly in the programming language, alternate characters can replace any of these frames) must animate with a delay of 0.25 seconds between each frame, with the previous frame being cleared be... | #11l | 11l | L
L(rod) ‘\|/-’
print(rod, end' "\r")
sleep(0.25) | Give a code snippet in #11l
Task
An animation with the following frames in the following order (if certain characters aren't available or can't be used correctly in the programming language, alternate characters can replace any of these frames) must animate with a delay of 0.25 seconds between each frame, with the pr... | christopher/rosetta-code | |
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... | #Euphoria | Euphoria | procedure print_args(sequence args)
for i = 1 to length(args) do
puts(1,args[i])
puts(1,' ')
end for
end procedure
print_args({"Mary", "had", "a", "little", "lamb"}) | Give a code snippet in #Euphoria
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.
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Continued_fraction | Continued fraction | continued fraction
Mathworld
a
0
+
b
1
a
1
+
b
2
a
2
+
b
3
a
3
+
⋱
{\displaystyle a_{0}+{\cfrac {b_{1}}{a_{1}+{\cfrac {b_{2}}{a_{2}+{\cfrac {b_{3}}{a_{3}+\ddots }}}}}}}
The task is to write a program which generates su... | #Factor | Factor | USING: arrays combinators io kernel locals math math.functions
math.ranges prettyprint sequences ;
IN: rosetta.cfrac
! Every continued fraction must implement these two words.
GENERIC: cfrac-a ( n cfrac -- a )
GENERIC: cfrac-b ( n cfrac -- b )
! square root of 2
SINGLETON: sqrt2
M: sqrt2 cfrac-a
! If n is 1, ... | Give a code snippet in #Factor
continued fraction
Mathworld
a
0
+
b
1
a
1
+
b
2
a
2
+
b
3
a
3
+
⋱
{\displaystyle a_{0}+{\cfrac {b_{1}}{a_{1}+{\cfrac {b_{2}}{a_{2}+{\cfrac {b_{3}}{a_{3}+\ddots }}}}}}}
The task is to wr... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Parametric_polymorphism | Parametric polymorphism | Parametric Polymorphism
type variables
Task
Write a small example for a type declaration that is parametric over another type, together with a short bit of code (and its type signature) that uses it.
A good example is a container type, let's say a binary tree, together with some function that traverses the tree, ... | #Icon_and_Unicon | Icon and Unicon | procedure main()
bTree := [1, [2, [4, [7]], [5]], [3, [6, [8], [9]]]]
mapTree(bTree, write)
bTree := [1, ["two", ["four", [7]], [5]], [3, ["six", ["eight"], [9]]]]
mapTree(bTree, write)
end
procedure mapTree(tree, f)
every f(\tree[1]) | mapTree(!tree[2:0], f)
end | Give a code snippet in #Icon_and_Unicon
Parametric Polymorphism
type variables
Task
Write a small example for a type declaration that is parametric over another type, together with a short bit of code (and its type signature) that uses it.
A good example is a container type, let's say a binary tree, together wit... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Monty_Hall_problem | Monty Hall problem |
Suppose you're on a game show and you're given the choice of three doors.
Behind one door is a car; behind the others, goats.
The car and the goats were placed randomly behind the doors before the show.
Rules of the game
After you have chosen a door, the door remains closed for the time being.
The game show hos... | #PicoLisp | PicoLisp | (de montyHall (Keep)
(let (Prize (rand 1 3) Choice (rand 1 3))
(if Keep # Keeping the first choice?
(= Prize Choice) # Yes: Monty's choice doesn't matter
(<> Prize Choice) ) ) ) # Else: Win if your first choice was wrong
(prinl
"Strategy KEEP -> "
(let ... | Give a code snippet in #PicoLisp
Suppose you're on a game show and you're given the choice of three doors.
Behind one door is a car; behind the others, goats.
The car and the goats were placed randomly behind the doors before the show.
Rules of the game
After you have chosen a door, the door remains closed for ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Hash_join | Hash join | An inner join is an operation that combines two data tables into one table, based on matching column values. The simplest way of implementing this operation is the nested loop join algorithm, but a more scalable alternative is the hash join algorithm.
Task[edit]
Implement the "hash join" algorithm, and demonstrate tha... | #Mathematica_.2F_Wolfram_Language | Mathematica / Wolfram Language | hashJoin[table1_List,table1colindex_Integer,table2_List,table2colindex_Integer]:=Module[{h,f,t1,t2,tmp},
t1=If[table1colindex != 1,table1[[All,Prepend[Delete[Range@Length@table1[[1]],table1colindex],table1colindex]]],table1];
t2=If[table2colindex != 1, table2[[All,Prepend[Delete[Range@Length@table2[[1]],table2colindex]... | Give a code snippet in #Mathematica_.2F_Wolfram_Language
An inner join is an operation that combines two data tables into one table, based on matching column values. The simplest way of implementing this operation is the nested loop join algorithm, but a more scalable alternative is the hash join algorithm.
Task[edit... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Caesar_cipher | Caesar cipher |
Task
Implement a Caesar cipher, both encoding and decoding.
The key is an integer from 1 to 25.
This cipher rotates (either towards left or right) the letters of the alphabet (A to Z).
The encoding replaces each letter with the 1st to 25th next letter in the alphabet (wrapping Z to A).
So key 2 encrypts "HI" to... | #PowerShell | PowerShell | # Author: M. McNabb
function Get-CaesarCipher
{
Param
(
[Parameter(
Mandatory=$true,ValueFromPipeline=$true)]
[string]
$Text,
[ValidateRange(1,25)]
[int]
$Key = 1,
[switch]
$Decode
)
begin
{
$LowerAlpha = [char]'a'..[char]'z'
$UpperAlpha = [char]'A'..[char]'Z'
}
process
{
$Chars = $Text.ToCharAr... | Give a code snippet in #PowerShell
Task
Implement a Caesar cipher, both encoding and decoding.
The key is an integer from 1 to 25.
This cipher rotates (either towards left or right) the letters of the alphabet (A to Z).
The encoding replaces each letter with the 1st to 25th next letter in the alphabet (wrapping... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Hello_world/Text | Hello world/Text | Hello world/Text is part of Short Circuit's Console Program Basics selection.
Task
Display the string Hello world! on a text console.
Related tasks
Hello world/Graphical
Hello world/Line Printer
Hello world/Newbie
Hello world/Newline omission
Hello world/Standard error
Hello world/Web server
| #Elisa | Elisa | "Hello world!"? | Give a code snippet in #Elisa
Hello world/Text is part of Short Circuit's Console Program Basics selection.
Task
Display the string Hello world! on a text console.
Related tasks
Hello world/Graphical
Hello world/Line Printer
Hello world/Newbie
Hello world/Newline omission
Hello world/Standard error
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Determine_if_a_string_is_numeric | Determine if a string is numeric | Task
Create a boolean function which takes in a string and tells whether it is a numeric string (floating point and negative numbers included) in the syntax the language uses for numeric literals or numbers converted from strings.
Other tasks related to string operations:
Metrics
Array length
String length
Cop... | #8th | 8th | : number? >n >kind ns:n n:= ; | Give a code snippet in #8th
Task
Create a boolean function which takes in a string and tells whether it is a numeric string (floating point and negative numbers included) in the syntax the language uses for numeric literals or numbers converted from strings.
Other tasks related to string operations:
Metrics
Arr... | christopher/rosetta-code | |
http://rosettacode.org/wiki/FizzBuzz | FizzBuzz | Task
Write a program that prints the integers from 1 to 100 (inclusive).
But:
for multiples of three, print Fizz (instead of the number)
for multiples of five, print Buzz (instead of the number)
for multiples of both three and five, print FizzBuzz (instead of the number)
... | #Vala | Vala | int main() {
for (int i = 1; i <= 100; i++) {
if (i % 3 == 0) stdout.printf("Fizz\n");
if (i % 5 == 0) stdout.printf("Buzz\n");
if (i % 15 == 0) stdout.printf("FizzBuzz\n");
if (i % 3 != 0 && i % 5 != 0) stdout.printf("%d\n", i);
}
return 0;;
} | Give a code snippet in #Vala
Task
Write a program that prints the integers from 1 to 100 (inclusive).
But:
for multiples of three, print Fizz (instead of the number)
for multiples of five, print Buzz (instead of the number)
for multiples of both three and five, print FizzBuzz ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Read_a_configuration_file | Read a configuration file | The task is to read a configuration file in standard configuration file format,
and set variables accordingly.
For this task, we have a configuration file as follows:
# This is a configuration file in standard configuration file format
#
# Lines beginning with a hash or a semicolon are ignored by the application
# pr... | #RapidQ | RapidQ |
type TSettings extends QObject
FullName as string
FavouriteFruit as string
NeedSpelling as integer
SeedsRemoved as integer
OtherFamily as QStringlist
Constructor
FullName = ""
FavouriteFruit = ""
NeedSpelling = 0
SeedsRemoved = 0
OtherFamily.clear
... | Give a code snippet in #RapidQ
The task is to read a configuration file in standard configuration file format,
and set variables accordingly.
For this task, we have a configuration file as follows:
# This is a configuration file in standard configuration file format
#
# Lines beginning with a hash or a semicolon are... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sorting_algorithms/Merge_sort | Sorting algorithms/Merge sort |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
... | #C | C | #include <stdio.h>
#include <stdlib.h>
void merge (int *a, int n, int m) {
int i, j, k;
int *x = malloc(n * sizeof (int));
for (i = 0, j = m, k = 0; k < n; k++) {
x[k] = j == n ? a[i++]
: i == m ? a[j++]
: a[j] < a[i] ? a[j++]
: a[i++]... | Give a code snippet in #C
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Singly-linked_list/Element_definition | Singly-linked list/Element definition | singly-linked list
See also
Array
Associative array: Creation, Iteration
Collections
Compound data type
Doubly-linked list: Definition, Element definition, Element insertion, List Traversal, Element Removal
Linked list
Queue: Definition, Usage
Set
Singly-linked list: Element definition, Element insertion, Lis... | #Modula-3 | Modula-3 | TYPE
Link = REF LinkRcd;
LinkRcd = RECORD
Next: Link;
Data: INTEGER
END; | Give a code snippet in #Modula-3
singly-linked list
See also
Array
Associative array: Creation, Iteration
Collections
Compound data type
Doubly-linked list: Definition, Element definition, Element insertion, List Traversal, Element Removal
Linked list
Queue: Definition, Usage
Set
Singly-linked list: Element ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Anonymous_recursion | Anonymous recursion | While implementing a recursive function, it often happens that we must resort to a separate helper function to handle the actual recursion.
This is usually the case when directly calling the current function would waste too many resources (stack space, execution time), causing unwanted side-effects, and/or the f... | #Scala | Scala | def Y[A, B](f: (A ⇒ B) ⇒ (A ⇒ B)): A ⇒ B = f(Y(f))(_)
def fib(n: Int): Option[Int] =
if (n < 0) None
else Some(Y[Int, Int](f ⇒ i ⇒
if (i < 2) 1
else f(i - 1) + f(i - 2))(n))
-2 to 5 map (n ⇒ (n, fib(n))) foreach println | Give a code snippet in #Scala
While implementing a recursive function, it often happens that we must resort to a separate helper function to handle the actual recursion.
This is usually the case when directly calling the current function would waste too many resources (stack space, execution time), causing unwant... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Magic_constant | Magic constant | A magic square is a square grid containing consecutive integers from 1 to N², arranged so that every row, column and diagonal adds up to the same number. That number is a constant. There is no way to create a valid N x N magic square that does not sum to the associated constant.
EG
A 3 x 3 magic square always sums to ... | #Julia | Julia | using Lazy
magic(x) = (1 + x^2) * x ÷ 2
magics = @>> Lazy.range() map(magic) filter(x -> x > 10) # first 2 values are filtered out
println("First 20 magic constants: ", Int.(take(20, magics)))
println("Thousandth magic constant is: ", collect(take(1000, magics))[end])
println("Smallest magic square with constant gr... | Give a code snippet in #Julia
A magic square is a square grid containing consecutive integers from 1 to N², arranged so that every row, column and diagonal adds up to the same number. That number is a constant. There is no way to create a valid N x N magic square that does not sum to the associated constant.
EG
A 3 x... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Short-circuit_evaluation | Short-circuit evaluation | Control Structures
These are examples of control structures. You may also be interested in:
Conditional structures
Exceptions
Flow-control structures
Loops
Assume functions a and b return boolean values, and further, the execution of function b takes considerable resources without side effects, an... | #Erlang | Erlang |
-module( short_circuit_evaluation ).
-export( [task/0] ).
task() ->
[task_helper(X, Y) || X <- [true, false], Y <- [true, false]].
a( Boolean ) ->
io:fwrite( " a ~p~n", [Boolean] ),
Boolean.
b( Boolean ) ->
io:fwrite( " b ~p~n", [Boolean] ),
Boolean.
task_helper( Boolean1, Boolean2 ) ->
io:fwrite(... | Give a code snippet in #Erlang
Control Structures
These are examples of control structures. You may also be interested in:
Conditional structures
Exceptions
Flow-control structures
Loops
Assume functions a and b return boolean values, and further, the execution of function b takes considerable re... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sum_and_product_puzzle | Sum and product puzzle | Task[edit]
Solve the "Impossible Puzzle":
X and Y are two different whole numbers greater than 1. Their sum is no greater than 100, and Y is greater than X. S and P are two mathematicians (and consequently perfect logicians); S knows the sum X+Y and P knows the product X*Y. Both S and P know all the information in th... | #Ruby | Ruby | def add(x,y) x + y end
def mul(x,y) x * y end
def sumEq(s,p) s.select{|q| add(*p) == add(*q)} end
def mulEq(s,p) s.select{|q| mul(*p) == mul(*q)} end
s1 = (a = *2...100).product(a).select{|x,y| x<y && x+y<100}
s2 = s1.select{|p| sumEq(s1,p).all?{|q| mulEq(s1,q).size != 1} }
s3 = s2.select{|p| (mulEq(s1,p) & s2).siz... | Give a code snippet in #Ruby
Task[edit]
Solve the "Impossible Puzzle":
X and Y are two different whole numbers greater than 1. Their sum is no greater than 100, and Y is greater than X. S and P are two mathematicians (and consequently perfect logicians); S knows the sum X+Y and P knows the product X*Y. Both S and P ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Dijkstra%27s_algorithm | Dijkstra's algorithm | This task has been clarified. Its programming examples are in need of review to ensure that they still fit the requirements of the task.
Dijkstra's algorithm, conceived by Dutch computer scientist Edsger Dijkstra in 1956 and published in 1959, is a graph search algorithm that solves the single-source shortest path pro... | #Wren | Wren | import "/dynamic" for Tuple
import "/trait" for Comparable
import "/sort" for Cmp, Sort
import "/set" for Set
var Edge = Tuple.create("Edge", ["v1", "v2", "dist"])
// One vertex of the graph, complete with mappings to neighboring vertices
class Vertex is Comparable {
static map { __map } // maps a name to its ... | Give a code snippet in #Wren
This task has been clarified. Its programming examples are in need of review to ensure that they still fit the requirements of the task.
Dijkstra's algorithm, conceived by Dutch computer scientist Edsger Dijkstra in 1956 and published in 1959, is a graph search algorithm that solves the s... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Bioinformatics/base_count | Bioinformatics/base count | Given this string representing ordered DNA bases:
CGTAAAAAATTACAACGTCCTTTGGCTATCTCTTAAACTCCTGCTAAATG
CTCGTGCTTTCCAATTATGTAAGCGTTCCGAGACGGGGTGGTCGATTCTG
AGGACAAAGGTCAAGATGGAGCGCATCGAACGCAATAAGGATCATTTGAT
GGGACGTTTCGTCGACAAAGTCTTGTTTCGAGAGTAACGGCTACCGTCTT
CGATTCTGCTTATAACACTATGTTCTTATGAAATGGATGTTCTGAGTTGG
TCAGTCCCAATGTG... | #Python | Python | from collections import Counter
def basecount(dna):
return sorted(Counter(dna).items())
def seq_split(dna, n=50):
return [dna[i: i+n] for i in range(0, len(dna), n)]
def seq_pp(dna, n=50):
for i, part in enumerate(seq_split(dna, n)):
print(f"{i*n:>5}: {part}")
print("\n BASECOUNT:")
t... | Give a code snippet in #Python
Given this string representing ordered DNA bases:
CGTAAAAAATTACAACGTCCTTTGGCTATCTCTTAAACTCCTGCTAAATG
CTCGTGCTTTCCAATTATGTAAGCGTTCCGAGACGGGGTGGTCGATTCTG
AGGACAAAGGTCAAGATGGAGCGCATCGAACGCAATAAGGATCATTTGAT
GGGACGTTTCGTCGACAAAGTCTTGTTTCGAGAGTAACGGCTACCGTCTT
CGATTCTGCTTATAACACTATGTTCTTATGAAA... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Host_introspection | Host introspection | Print the word size and endianness of the host machine.
See also: Variable size/Get
| #68000_Assembly | 68000 Assembly | TestEndianness:
LEA UserRam,A0
MOVE.L #$0000FFFF,(A0)
MOVE.B (A0),D0 ;read the 0th byte stored
BEQ isBigEndian ;if this was little endian, the bytes would be stored FF FF 00 00
;must have been little-endian. Spoiler alert: execution will never reach here
LEA LittleEndianMessage,A3
JSR PrintString
rts
isBigEndian:
... | Give a code snippet in #68000_Assembly
Print the word size and endianness of the host machine.
See also: Variable size/Get
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Knuth%27s_algorithm_S | Knuth's algorithm S | This is a method of randomly sampling n items from a set of M items, with equal probability; where M >= n and M, the number of items is unknown until the end.
This means that the equal probability sampling should be maintained for all successive items > n as they become available (although the content of successive sam... | #Ruby | Ruby | def s_of_n_creator(n)
sample = []
i = 0
Proc.new do |item|
i += 1
if i <= n
sample << item
elsif rand(i) < n
sample[rand(n)] = item
end
sample
end
end
frequency = Array.new(10,0)
100_000.times do
s_of_n = s_of_n_creator(3)
sample = nil
(0..9).each {|digit| sample = s_of_n... | Give a code snippet in #Ruby
This is a method of randomly sampling n items from a set of M items, with equal probability; where M >= n and M, the number of items is unknown until the end.
This means that the equal probability sampling should be maintained for all successive items > n as they become available (although... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Temperature_conversion | Temperature conversion | There are quite a number of temperature scales. For this task we will concentrate on four of the perhaps best-known ones:
Kelvin, Celsius, Fahrenheit, and Rankine.
The Celsius and Kelvin scales have the same magnitude, but different null points.
0 degrees Celsius corresponds to 273.15 kelvin.
0 kelvin is absolute z... | #PARI.2FGP | PARI/GP | f(x)=[x,x-273.15,1.8*x-459.67,1.8*x] | Give a code snippet in #PARI.2FGP
There are quite a number of temperature scales. For this task we will concentrate on four of the perhaps best-known ones:
Kelvin, Celsius, Fahrenheit, and Rankine.
The Celsius and Kelvin scales have the same magnitude, but different null points.
0 degrees Celsius corresponds to 273... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Shoelace_formula_for_polygonal_area | Shoelace formula for polygonal area | Given the n + 1 vertices x[0], y[0] .. x[N], y[N] of a simple polygon described in a clockwise direction, then the polygon's area can be calculated by:
abs( (sum(x[0]*y[1] + ... x[n-1]*y[n]) + x[N]*y[0]) -
(sum(x[1]*y[0] + ... x[n]*y[n-1]) + x[0]*y[N])
) / 2
(Where abs returns the absolute value)
Task
Write ... | #Java | Java | import java.util.List;
public class ShoelaceFormula {
private static class Point {
int x, y;
Point(int x, int y) {
this.x = x;
this.y = y;
}
@Override
public String toString() {
return String.format("(%d, %d)", x, y);
}
}
... | Give a code snippet in #Java
Given the n + 1 vertices x[0], y[0] .. x[N], y[N] of a simple polygon described in a clockwise direction, then the polygon's area can be calculated by:
abs( (sum(x[0]*y[1] + ... x[n-1]*y[n]) + x[N]*y[0]) -
(sum(x[1]*y[0] + ... x[n]*y[n-1]) + x[0]*y[N])
) / 2
(Where abs returns the... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Strip_a_set_of_characters_from_a_string | Strip a set of characters from a string | Task
Create a function that strips a set of characters from a string.
The function should take two arguments:
a string to be stripped
a string containing the set of characters to be stripped
The returned string should contain the first string, stripped of any characters in the second argument:
print str... | #F.C5.8Drmul.C3.A6 | Fōrmulæ | Public Sub Main()
Print StripChars("She was a soul stripper. She took my heart!", "aei")
End
'_____________________________________________________________________
Public Sub StripChars(sText As String, sRemove As String) As String
Dim siCount As Short
For siCount = 1 To Len(sRemove)
sText = Replace(sText, Mid(... | Give a code snippet in #F.C5.8Drmul.C3.A6
Task
Create a function that strips a set of characters from a string.
The function should take two arguments:
a string to be stripped
a string containing the set of characters to be stripped
The returned string should contain the first string, stripped of any cha... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sequence:_smallest_number_with_exactly_n_divisors | Sequence: smallest number with exactly n divisors | Calculate the sequence where each term an is the smallest natural number that has exactly n divisors.
Task
Show here, on this page, at least the first 15 terms of the sequence.
Related tasks
Sequence: smallest number greater than previous term with exactly n divisors
Sequence: nth number with exactly... | #XPL0 | XPL0 | func Divisors(N); \Return number of divisors of N
int N, Count, D;
[Count:= 0;
for D:= 1 to N do
if rem(N/D) = 0 then Count:= Count+1;
return Count;
];
int N, AN;
[for N:= 1 to 15 do
[AN:= 0;
repeat AN:= AN+1 until Divisors(AN) = N;
IntOut(0, AN); ChOut(0, ^ );
];
] | Give a code snippet in #XPL0
Calculate the sequence where each term an is the smallest natural number that has exactly n divisors.
Task
Show here, on this page, at least the first 15 terms of the sequence.
Related tasks
Sequence: smallest number greater than previous term with exactly n divisors
Seq... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Arithmetic/Rational | Arithmetic/Rational | Task
Create a reasonably complete implementation of rational arithmetic in the particular language using the idioms of the language.
Example
Define a new type called frac with binary operator "//" of two integers that returns a structure made up of the numerator and the denominator (as per a rational number).
Fur... | #Maple | Maple |
> a := 3 / 5;
a := 3/5
> numer( a );
3
> denom( a );
5
| Give a code snippet in #Maple
Task
Create a reasonably complete implementation of rational arithmetic in the particular language using the idioms of the language.
Example
Define a new type called frac with binary operator "//" of two integers that returns a structure made up of the numerator and the denominator (... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Levenshtein_distance | Levenshtein distance |
This page uses content from Wikipedia. The original article was at Levenshtein distance. 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)
In information theory and computer science, the Levenshtein ... | #360_Assembly | 360 Assembly | * Levenshtein distance - 22/04/2020
LEVENS CSECT
USING LEVENS,R13 base register
B 72(R15) skip savearea
DC 17F'0' savearea
SAVE (14,12) save previous context
ST R13,4(R15) link backward
... | Give a code snippet in #360_Assembly
This page uses content from Wikipedia. The original article was at Levenshtein distance. 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)
In information theory ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Loop_over_multiple_arrays_simultaneously | Loop over multiple arrays simultaneously | Task
Loop over multiple arrays (or lists or tuples or whatever they're called in
your language) and display the i th element of each.
Use your language's "for each" loop if it has one, otherwise iterate
through the collection in order with some other loop.
For this example, loop over the arrays:
... | #Maple | Maple | # Set up
L := [["a", "b", "c"],["A", "B", "C"], ["1", "2", "3"]];
M := Array(1..3, 1..3, L);
multi_loop := proc(M)
local i, j;
for i from 1 to upperbound(M, 1) do
for j from 1 to upperbound(M, 2) do
printf("%s", M[j, i]);
end do;
printf("\n");
end do;
end proc:
multi_loop(M); | Give a code snippet in #Maple
Task
Loop over multiple arrays (or lists or tuples or whatever they're called in
your language) and display the i th element of each.
Use your language's "for each" loop if it has one, otherwise iterate
through the collection in order with some other loop.
For this exam... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Cut_a_rectangle | Cut a rectangle | A given rectangle is made from m × n squares. If m and n are not both odd, then it is possible to cut a path through the rectangle along the square edges such that the rectangle splits into two connected pieces with the same shape (after rotating one of the pieces by 180°). All such paths for 2 × 2 and 4 × 3 rectangles... | #Phix | Phix | with javascript_semantics
integer show = 2, -- max number to show
-- (nb mirrors are not shown)
chance = 1000 -- 1=always, 2=50%, 3=33%, etc
sequence grid
integer gh, -- = length(grid),
gw -- = length(grid[1])
integer ty1, ty2, tx1, tx2 -- target {y,x}s
procedur... | Give a code snippet in #Phix
A given rectangle is made from m × n squares. If m and n are not both odd, then it is possible to cut a path through the rectangle along the square edges such that the rectangle splits into two connected pieces with the same shape (after rotating one of the pieces by 180°). All such paths ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Hello_world/Graphical | Hello world/Graphical |
Task
Display the string Goodbye, World! on a GUI object (alert box, plain window, text area, etc.).
Related task
Hello world/Text
| #Integer_BASIC | Integer BASIC |
10 REM FONT DERIVED FROM 04B-09 BY YUJI OSHIMOTO
20 GR
30 COLOR = 12
40 REM G
50 HLIN 0,5 AT 0 : HLIN 0,5 AT 1
60 VLIN 2,9 AT 0 : VLIN 2,9 AT 1
70 HLIN 2,5 AT 9 : HLIN 2,5 AT 8
80 VLIN 4,7 AT 5 : VLIN 4,7 AT 4
90 VLIN 4,5 AT 3
100 REM O
110 HLIN 7,12 AT 2 : HLIN 7,12 AT 3
120 HLIN 7,12 AT 8 : HLIN 7,12 AT 9
130 VLIN ... | Give a code snippet in #Integer_BASIC
Task
Display the string Goodbye, World! on a GUI object (alert box, plain window, text area, etc.).
Related task
Hello world/Text
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Unicode_variable_names | Unicode variable names | Task
Describe, and give a pointer to documentation on your languages use of characters beyond those of the ASCII character set in the naming of variables.
Show how to:
Set a variable with a name including the 'Δ', (delta character), to 1
Increment it
Print its value.
Related task
Case-sensitivity of identif... | #Delphi | Delphi | (* Compiled with Delphi XE *)
program UnicodeVariableName;
{$APPTYPE CONSOLE}
uses
SysUtils;
var
Δ: Integer;
begin
Δ:= 1;
Inc(Δ);
Writeln(Δ);
Readln;
end. | Give a code snippet in #Delphi
Task
Describe, and give a pointer to documentation on your languages use of characters beyond those of the ASCII character set in the naming of variables.
Show how to:
Set a variable with a name including the 'Δ', (delta character), to 1
Increment it
Print its value.
Related tas... | christopher/rosetta-code | |
http://rosettacode.org/wiki/A%2BB | A+B | A+B ─── a classic problem in programming contests, it's given so contestants can gain familiarity with the online judging system being used.
Task
Given two integers, A and B.
Their sum needs to be calculated.
Input data
Two integers are written in the input stream, separated by space(s):
(
−
1000
≤... | #Python | Python | try: raw_input
except: raw_input = input
print(sum(map(int, raw_input().split()))) | Give a code snippet in #Python
A+B ─── a classic problem in programming contests, it's given so contestants can gain familiarity with the online judging system being used.
Task
Given two integers, A and B.
Their sum needs to be calculated.
Input data
Two integers are written in the input stream, separat... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Algebraic_data_types | Algebraic data types | Some languages offer direct support for algebraic data types and pattern matching on them. While this of course can always be simulated with manual tagging and conditionals, it allows for terse code which is easy to read, and can represent the algorithm directly.
Task
As an example, implement insertion in a red-bla... | #Nim | Nim | import fusion/matching
{.experimental: "caseStmtMacros".}
type
Colour = enum Empty, Red, Black
RBTree[T] = ref object
colour: Colour
left, right: RBTree[T]
value: T
proc `[]`[T](r: RBTree[T], idx: static[FieldIndex]): auto =
## enables tuple syntax for unpacking and matching
when idx == 0: r.col... | Give a code snippet in #Nim
Some languages offer direct support for algebraic data types and pattern matching on them. While this of course can always be simulated with manual tagging and conditionals, it allows for terse code which is easy to read, and can represent the algorithm directly.
Task
As an example, imp... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sorting_algorithms/Selection_sort | Sorting algorithms/Selection sort |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
... | #C.2B.2B | C++ | g++ -std=c++11 selection.cpp
| Give a code snippet in #C.2B.2B
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Haversine_formula | Haversine formula |
This page uses content from Wikipedia. The original article was at Haversine formula. 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)
The haversine formula is an equation important in navigation, g... | #ERRE | ERRE | % Implemented by Claudio Larini
PROGRAM HAVERSINE_DEMO
!$DOUBLE
CONST DIAMETER=12745.6
FUNCTION DEG2RAD(X)
DEG2RAD=X*π/180
END FUNCTION
FUNCTION RAD2DEG(X)
RAD2DEG=X*180/π
END FUNCTION
PROCEDURE HAVERSINE_DIST(TH1,PH1,TH2,PH2->RES)
LOCAL DX,DY,DZ
PH1=DEG2RAD(PH1-PH2)
TH1=DEG2RAD(TH1)
... | Give a code snippet in #ERRE
This page uses content from Wikipedia. The original article was at Haversine formula. 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)
The haversine formula is an equat... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Loops/For_with_a_specified_step | Loops/For with a specified step |
Task
Demonstrate a for-loop where the step-value is greater than one.
Related tasks
Loop over multiple arrays simultaneously
Loops/Break
Loops/Continue
Loops/Do-while
Loops/Downward for
Loops/For
Loops/For with a specified step
Loops/Foreach
Loops/Increment loop index within loop b... | #Hy | Hy | (for [i (range 1 10 2)] (print i)) | Give a code snippet in #Hy
Task
Demonstrate a for-loop where the step-value is greater than one.
Related tasks
Loop over multiple arrays simultaneously
Loops/Break
Loops/Continue
Loops/Do-while
Loops/Downward for
Loops/For
Loops/For with a specified step
Loops/Foreach
Loops/Increm... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Constrained_genericity | Constrained genericity | Constrained genericity or bounded quantification means
that a parametrized type or function (see parametric polymorphism)
can only be instantiated on types fulfilling some conditions,
even if those conditions are not used in that function.
Say a type is called "eatable" if you can call the function eat on it.
Write a ... | #Nemerle | Nemerle | using System.Collections.Generic;
interface IEatable
{
Eat() : void;
}
class FoodBox[T] : IEnumerable[T]
where T : IEatable
{
private _foods : list[T] = [];
public this() {}
public this(items : IEnumerable[T])
{
this._foods = $[food | food in items];
}
public Add(food : T... | Give a code snippet in #Nemerle
Constrained genericity or bounded quantification means
that a parametrized type or function (see parametric polymorphism)
can only be instantiated on types fulfilling some conditions,
even if those conditions are not used in that function.
Say a type is called "eatable" if you can call... | christopher/rosetta-code | |
http://rosettacode.org/wiki/System_time | System time | Task
Output the system time (any units will do as long as they are noted) either by a system command or one built into the language.
The system time can be used for debugging, network information, random number seeds, or something as simple as program performance.
Related task
Date format
See also
Retr... | #DCL | DCL | $ start_time = f$time()
$ wait 0::10
$ end_time = f$time()
$ write sys$output "start time was ", start_time
$ write sys$output "end time was ", end_time
$ write sys$output "delta time is ", f$delta_time( start_time, end_time ) | Give a code snippet in #DCL
Task
Output the system time (any units will do as long as they are noted) either by a system command or one built into the language.
The system time can be used for debugging, network information, random number seeds, or something as simple as program performance.
Related task
Da... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Continued_fraction | Continued fraction | continued fraction
Mathworld
a
0
+
b
1
a
1
+
b
2
a
2
+
b
3
a
3
+
⋱
{\displaystyle a_{0}+{\cfrac {b_{1}}{a_{1}+{\cfrac {b_{2}}{a_{2}+{\cfrac {b_{3}}{a_{3}+\ddots }}}}}}}
The task is to write a program which generates su... | #Scheme | Scheme | #!r6rs
(import (rnrs base (6))
(srfi :41 streams))
(define nats (stream-cons 0 (stream-map (lambda (x) (+ x 1)) nats)))
(define (build-stream fn) (stream-map fn nats))
(define (stream-cycle s . S)
(cond
((stream-null? (car S)) stream-null)
(else (stream-cons (stream-car s)
... | Give a code snippet in #Scheme
continued fraction
Mathworld
a
0
+
b
1
a
1
+
b
2
a
2
+
b
3
a
3
+
⋱
{\displaystyle a_{0}+{\cfrac {b_{1}}{a_{1}+{\cfrac {b_{2}}{a_{2}+{\cfrac {b_{3}}{a_{3}+\ddots }}}}}}}
The task is to wr... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Search_a_list | Search a list | Task[edit]
Find the index of a string (needle) in an indexable, ordered collection of strings (haystack).
Raise an exception if the needle is missing.
If there is more than one occurrence then return the smallest index to the needle.
Extra credit
Return the largest index to a needle that has multiple occurrences in ... | #Objeck | Objeck | use Collection;
class Test {
function : Main(args : String[]) ~ Nil {
haystack := ["Zig","Zag","Wally","Ronald","Bush","Krusty","Charlie","Bush","Bozo"];
values := CompareVector->New();
each(i : haystack) {
values->AddBack(haystack[i]->As(Compare));
};
needles := ["Washington", "Bush"];
... | Give a code snippet in #Objeck
Task[edit]
Find the index of a string (needle) in an indexable, ordered collection of strings (haystack).
Raise an exception if the needle is missing.
If there is more than one occurrence then return the smallest index to the needle.
Extra credit
Return the largest index to a needle t... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Reverse_words_in_a_string | Reverse words in a string | Task
Reverse the order of all tokens in each of a number of strings and display the result; the order of characters within a token should not be modified.
Example
Hey you, Bub! would be shown reversed as: Bub! you, Hey
Tokens are any non-space characters separated by spaces (formally, white-space); t... | #Pascal | Pascal | program Reverse_words(Output);
{$H+}
const
nl = chr(10); // Linefeed
sp = chr(32); // Space
TXT =
'---------- Ice and Fire -----------'+nl+
nl+
'fire, in end will world the say Some'+nl+
'ice. in say Some'+nl+
'desire of tasted I''ve what From'+nl+
'fire. favor who those with hold I'+nl+
nl+
'..... | Give a code snippet in #Pascal
Task
Reverse the order of all tokens in each of a number of strings and display the result; the order of characters within a token should not be modified.
Example
Hey you, Bub! would be shown reversed as: Bub! you, Hey
Tokens are any non-space characters separated by spa... | christopher/rosetta-code | |
http://rosettacode.org/wiki/CSV_data_manipulation | CSV data manipulation | CSV spreadsheet files are suitable for storing tabular data in a relatively portable way.
The CSV format is flexible but somewhat ill-defined.
For present purposes, authors may assume that the data fields contain no commas, backslashes, or quotation marks.
Task
Read a CSV file, change some values and save the cha... | #JavaScript | JavaScript | (function () {
'use strict';
// splitRegex :: Regex -> String -> [String]
function splitRegex(rgx, s) {
return s.split(rgx);
}
// lines :: String -> [String]
function lines(s) {
return s.split(/[\r\n]/);
}
// unlines :: [String] -> String
function unlines(xs) {
... | Give a code snippet in #JavaScript
CSV spreadsheet files are suitable for storing tabular data in a relatively portable way.
The CSV format is flexible but somewhat ill-defined.
For present purposes, authors may assume that the data fields contain no commas, backslashes, or quotation marks.
Task
Read a CSV file,... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Rep-string | Rep-string | Given a series of ones and zeroes in a string, define a repeated string or rep-string as a string which is created by repeating a substring of the first N characters of the string truncated on the right to the length of the input string, and in which the substring appears repeated at least twice in the original.
For e... | #Common_Lisp | Common Lisp |
(ql:quickload :alexandria)
(defun rep-stringv (a-str &optional (max-rotation (floor (/ (length a-str) 2))))
;; Exit condition if no repetition found.
(cond ((< max-rotation 1) "Not a repeating string")
;; Two checks:
;; 1. Truncated string must be equal to rotation by repetion size.
;; 2. ... | Give a code snippet in #Common_Lisp
Given a series of ones and zeroes in a string, define a repeated string or rep-string as a string which is created by repeating a substring of the first N characters of the string truncated on the right to the length of the input string, and in which the substring appears repeated a... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Rename_a_file | Rename a file | Task
Rename:
a file called input.txt into output.txt and
a directory called docs into mydocs.
This should be done twice:
once "here", i.e. in the current working directory and once in the filesystem root.
It can be assumed that the user has the rights to do so.
(In unix-type s... | #REBOL | REBOL | rename %input.txt %output.txt
rename %docs/ %mydocs/
; Unix. Note that there's no path specification used for the
; new name. "Rename" is not "move".
rename %/input.txt %output.txt
rename %/docs/ %mydocs/
; DOS/Windows:
rename %/c/input.txt %output.txt
rename %/c/docs/ %mydocs/
; Because REBOL treats data ac... | Give a code snippet in #REBOL
Task
Rename:
a file called input.txt into output.txt and
a directory called docs into mydocs.
This should be done twice:
once "here", i.e. in the current working directory and once in the filesystem root.
It can be assumed that the user has the ri... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Doubly-linked_list/Definition | Doubly-linked list/Definition | Define the data structure for a complete Doubly Linked List.
The structure should support adding elements to the head, tail and middle of the list.
The structure should not allow circular loops
See also
Array
Associative array: Creation, Iteration
Collections
Compound data type
Doubly-linked list: Definitio... | #Fortran | Fortran |
module dlist
implicit none
type node
type(node), pointer :: next => null()
type(node), pointer :: prev => null()
integer :: data
end type node
type dll
type(node), pointer :: head => null()
type(node), pointer :: tail => null()
integer :: num_nodes = 0
end type dll
public... | Give a code snippet in #Fortran
Define the data structure for a complete Doubly Linked List.
The structure should support adding elements to the head, tail and middle of the list.
The structure should not allow circular loops
See also
Array
Associative array: Creation, Iteration
Collections
Compound data ty... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Fast_Fourier_transform | Fast Fourier transform | Task
Calculate the FFT (Fast Fourier Transform) of an input sequence.
The most general case allows for complex numbers at the input
and results in a sequence of equal length, again of complex numbers.
If you need to restrict yourself to real numbers, the output should
be the magnitude (i.e.: sqrt(re2 + im2)... | #Nim | Nim | import math, complex, strutils
# Works with floats and complex numbers as input
proc fft[T: float | Complex[float]](x: openarray[T]): seq[Complex[float]] =
let n = x.len
if n == 0: return
result.newSeq(n)
if n == 1:
result[0] = (when T is float: complex(x[0]) else: x[0])
return
var evens, odds... | Give a code snippet in #Nim
Task
Calculate the FFT (Fast Fourier Transform) of an input sequence.
The most general case allows for complex numbers at the input
and results in a sequence of equal length, again of complex numbers.
If you need to restrict yourself to real numbers, the output should
be the magnitu... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Integer_sequence | Integer sequence | Task
Create a program that, when run, would display all integers from 1 to ∞ (or any relevant implementation limit), in sequence (i.e. 1, 2, 3, 4, etc) if given enough time.
An example may not be able to reach arbitrarily-large numbers based on implementations limits. For example, if integer... | #Lasso | Lasso | local(number = 1)
while(#number > 0) => {^
#number++
' '
//#number > 100 ? #number = -2 // uncomment this row if you want to halt the run after proving concept
^} | Give a code snippet in #Lasso
Task
Create a program that, when run, would display all integers from 1 to ∞ (or any relevant implementation limit), in sequence (i.e. 1, 2, 3, 4, etc) if given enough time.
An example may not be able to reach arbitrarily-large numbers based on implementations li... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Averages/Mean_time_of_day | Averages/Mean time of day | Task[edit]
A particular activity of bats occurs at these times of the day:
23:00:17, 23:40:20, 00:12:45, 00:17:19
Using the idea that there are twenty-four hours in a day,
which is analogous to there being 360 degrees in a circle,
map times of day to and from angles;
and using the ideas of Averages/Mean angle
compute ... | #SQL.2FPostgreSQL | SQL/PostgreSQL |
--Setup table for testing
CREATE TABLE time_table(times TIME);
INSERT INTO time_table VALUES ('23:00:17'::TIME),('23:40:20'::TIME),('00:12:45'::TIME),('00:17:19'::TIME)
--Compute mean time
SELECT to_timestamp((degrees(atan2(AVG(sin),AVG(cos))))* (24*60*60)/360)::TIME
FROM
(SELECT
cos(radians(t*360/(24*60*60))),si... | Give a code snippet in #SQL.2FPostgreSQL
Task[edit]
A particular activity of bats occurs at these times of the day:
23:00:17, 23:40:20, 00:12:45, 00:17:19
Using the idea that there are twenty-four hours in a day,
which is analogous to there being 360 degrees in a circle,
map times of day to and from angles;
and using... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Hickerson_series_of_almost_integers | Hickerson series of almost integers | The following function, due to D. Hickerson, is said to generate "Almost integers" by the
"Almost Integer" page of Wolfram MathWorld, (December 31 2013). (See formula numbered 51.)
The function is:
h
(
n
)
=
n
!
2
(
ln
2
)
n
+
1
{\displaystyle h(n)={\operatorname {n} ! \ove... | #FreeBASIC | FreeBASIC | ' version 08-10-2016
' compile with: fbc -s gui
#Include Once "gmp.bi"
#Macro init_float_size (big_float ,size)
Dim As Mpf_ptr big_float = Allocate( Len( __mpf_struct))
Mpf_init2( big_float,size)
#EndMacro
#Macro mpf_remove(big_float)
Mpf_clear(big_float)
DeAllocate (big_float)
#EndMacro
Screen 20
ini... | Give a code snippet in #FreeBASIC
The following function, due to D. Hickerson, is said to generate "Almost integers" by the
"Almost Integer" page of Wolfram MathWorld, (December 31 2013). (See formula numbered 51.)
The function is:
h
(
n
)
=
n
!
2
(
ln
2
)
n
+
1
{\displays... | christopher/rosetta-code | |
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... | #Tcl | Tcl | proc dot {A B} {
lassign $A a1 a2 a3
lassign $B b1 b2 b3
expr {$a1*$b1 + $a2*$b2 + $a3*$b3}
}
proc cross {A B} {
lassign $A a1 a2 a3
lassign $B b1 b2 b3
list [expr {$a2*$b3 - $a3*$b2}] \
[expr {$a3*$b1 - $a1*$b3}] \
[expr {$a1*$b2 - $a2*$b1}]
}
proc scalarTriple {A B C} {
dot $A [cross $... | Give a code snippet in #Tcl
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 numb... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Averages/Arithmetic_mean | Averages/Arithmetic mean | Task[edit]
Write a program to find the mean (arithmetic average) of a numeric vector.
In case of a zero-length input, since the mean of an empty set of numbers is ill-defined, the program may choose to behave in any way it deems appropriate, though if the programming language has an established convention for conveyin... | #Plain_English | Plain English | To run:
Start up.
Demonstrate finding the arithmetic mean.
Wait for the escape key.
Shut down.
An entry is a thing with a fraction.
A list is some entries.
A sum is a fraction.
A mean is a fraction.
To demonstrate finding the arithmetic mean:
Create an example list.
Write "A list: " then the example list on the con... | Give a code snippet in #Plain_English
Task[edit]
Write a program to find the mean (arithmetic average) of a numeric vector.
In case of a zero-length input, since the mean of an empty set of numbers is ill-defined, the program may choose to behave in any way it deems appropriate, though if the programming language has... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Fibonacci_sequence | Fibonacci sequence | The Fibonacci sequence is a sequence Fn of natural numbers defined recursively:
F0 = 0
F1 = 1
Fn = Fn-1 + Fn-2, if n>1
Task
Write a function to generate the nth Fibonacci number.
Solutions can be iterative or recursive (though recursive solutions are generally considered too slow ... | #Oforth | Oforth | : fib 0 1 rot #[ tuck + ] times drop ; | Give a code snippet in #Oforth
The Fibonacci sequence is a sequence Fn of natural numbers defined recursively:
F0 = 0
F1 = 1
Fn = Fn-1 + Fn-2, if n>1
Task
Write a function to generate the nth Fibonacci number.
Solutions can be iterative or recursive (though recursive solutions ar... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Levenshtein_distance | Levenshtein distance |
This page uses content from Wikipedia. The original article was at Levenshtein distance. 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)
In information theory and computer science, the Levenshtein ... | #Prolog | Prolog | levenshtein(S, T, R) :-
length(S, M),
M1 is M+1,
length(T, N),
N1 is N+1,
length(Lev, N1),
maplist(init(M1), Lev),
numlist(0, N, LN),
maplist(init_n, LN, Lev),
nth0(0, Lev, Lev0),
numlist(0, M, Lev0),
% compute_levenshtein distance
numlist(1, N, LN1),
maplist(work_on_T(Lev, S), LN1, T),
last(Lev, LevLas... | Give a code snippet in #Prolog
This page uses content from Wikipedia. The original article was at Levenshtein distance. 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)
In information theory and co... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Factorial | Factorial | Definitions
The factorial of 0 (zero) is defined as being 1 (unity).
The Factorial Function of a positive integer, n, is defined as the product of the sequence:
n, n-1, n-2, ... 1
Task
Write a function to return the factorial of a number.
Solutions can be iterat... | #MAXScript | MAXScript | fn factorial n =
(
if n == 0 then return 1
local fac = 1
for i in 1 to n do
(
fac *= i
)
fac
) | Give a code snippet in #MAXScript
Definitions
The factorial of 0 (zero) is defined as being 1 (unity).
The Factorial Function of a positive integer, n, is defined as the product of the sequence:
n, n-1, n-2, ... 1
Task
Write a function to return the factorial of... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Abundant,_deficient_and_perfect_number_classifications | Abundant, deficient and perfect number classifications | These define three classifications of positive integers based on their proper divisors.
Let P(n) be the sum of the proper divisors of n where the proper divisors are all positive divisors of n other than n itself.
if P(n) < n then n is classed as deficient (OEIS A005100).
if P(n)... | #BCPL | BCPL | get "libhdr"
manifest $( maximum = 20000 $)
let calcpdivs(p, max) be
$( for i=0 to max do p!i := 0
for i=1 to max/2
$( let j = i+i
while 0 < j <= max
$( p!j := p!j + i
j := j + i
$)
$)
$)
let classify(p, n, def, per, ab) be
$( let z = 0<=p!n<n -> def, p!n=n -> pe... | Give a code snippet in #BCPL
These define three classifications of positive integers based on their proper divisors.
Let P(n) be the sum of the proper divisors of n where the proper divisors are all positive divisors of n other than n itself.
if P(n) < n then n is classed as deficient ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Even_or_odd | Even or odd | Task
Test whether an integer is even or odd.
There is more than one way to solve this task:
Use the even and odd predicates, if the language provides them.
Check the least significant digit. With binary integers, i bitwise-and 1 equals 0 iff i is even, or equals 1 iff i is odd.
Divide i by 2. The remainder equals... | #MiniScript | MiniScript | for i in range(-4, 4)
if i % 2 == 0 then print i + " is even" else print i + " is odd"
end for | Give a code snippet in #MiniScript
Task
Test whether an integer is even or odd.
There is more than one way to solve this task:
Use the even and odd predicates, if the language provides them.
Check the least significant digit. With binary integers, i bitwise-and 1 equals 0 iff i is even, or equals 1 iff i is odd.
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Named_parameters | Named parameters | Create a function which takes in a number of arguments which are specified by name rather than (necessarily) position, and show how to call the function. If the language supports reordering the arguments or optionally omitting some of them, note this.
Note:
Named parameters relies on being able to use the names give... | #M2000_Interpreter | M2000 Interpreter |
module namedparam (x as decimal=10, y as integer=50) {
Print type$(x), x
Print type$(y), y
}
namedparam 10, 20
namedparam ?, ?
Push 1, 2 : namedparam
Stack New {
\\ it is empty
namedparam
namedparam %y=500
namedparam %x=20
}
namedparam %x=1, %y=1
| Give a code snippet in #M2000_Interpreter
Create a function which takes in a number of arguments which are specified by name rather than (necessarily) position, and show how to call the function. If the language supports reordering the arguments or optionally omitting some of them, note this.
Note:
Named parameters... | christopher/rosetta-code | |
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 ... | #F.C5.8Drmul.C3.A6 | Fōrmulæ | offset = 32; //Distance from triangle vertices to edges of window
//triangle vertex coordinates
x1 = room_width / 2;
y1 = offset;
x2 = room_width - offset;
y2 = room_height - offset;
x3 = offset;
y3 = room_height - offset;
//Coords of randomly chosen vertex (set to 0 to start, will automatically be set in step even... | Give a code snippet in #F.C5.8Drmul.C3.A6
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... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Horner%27s_rule_for_polynomial_evaluation | Horner's rule for polynomial evaluation | A fast scheme for evaluating a polynomial such as:
−
19
+
7
x
−
4
x
2
+
6
x
3
{\displaystyle -19+7x-4x^{2}+6x^{3}\,}
when
x
=
3
{\displaystyle x=3\;}
.
is to arrange the computation as follows:
(
(
(
(
0
)
x
+
6
)
x
+
(
−
4
)
)
x
+
7
)
x
+
(
−
19
)
{\displaystyle ((((0)x+6)x+(-4))x... | #Oberon-2 | Oberon-2 |
MODULE HornerRule;
IMPORT
Out;
TYPE
Coefs = POINTER TO ARRAY OF LONGINT;
VAR
coefs: Coefs;
PROCEDURE Eval(coefs: ARRAY OF LONGINT;size,x: LONGINT): LONGINT;
VAR
i,acc: LONGINT;
BEGIN
acc := 0;
FOR i := LEN(coefs) - 1 TO 0 BY -1 DO
acc := acc * x + coefs[i]
END;
RETURN acc
END Eval;
BEGIN
NEW... | Give a code snippet in #Oberon-2
A fast scheme for evaluating a polynomial such as:
−
19
+
7
x
−
4
x
2
+
6
x
3
{\displaystyle -19+7x-4x^{2}+6x^{3}\,}
when
x
=
3
{\displaystyle x=3\;}
.
is to arrange the computation as follows:
(
(
(
(
0
)
x
+
6
)
x
+
(
−
4
)
)
x
+
7
)
x
+
(
−
19
)
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Towers_of_Hanoi | Towers of Hanoi | Task
Solve the Towers of Hanoi problem with recursion.
| #Oz | Oz | declare
proc {TowersOfHanoi N From To Via}
if N > 0 then
{TowersOfHanoi N-1 From Via To}
{System.showInfo "Move from "#From#" to "#To}
{TowersOfHanoi N-1 Via To From}
end
end
in
{TowersOfHanoi 4 left middle right} | Give a code snippet in #Oz
Task
Solve the Towers of Hanoi problem with recursion.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Four_bit_adder | Four bit adder | Task
"Simulate" a four-bit adder.
This design can be realized using four 1-bit full adders.
Each of these 1-bit full adders can be built with two half adders and an or gate. ;
Finally a half adder can be made using an xor gate and an and gate.
The xor gate can be made using two nots, two ands ... | #zkl | zkl | fcn xor(a,b) // a,b are 1|0 -->a^b(1|0)
{ a.bitAnd(b.bitNot()).bitOr(b.bitAnd(a.bitNot())) }
fcn halfAdder(a,b) // -->(carry, a+b) (1|0)
{ return(a.bitAnd(b), xor(a,b)) }
fcn fullBitAdder(c, a,b){ //-->(carry, a+b+c), a,b,c are 1|0
c1,s := halfAdder(a,c);
c2,s := halfAdder(s,b);
c3 := c1.bitOr(c2);... | Give a code snippet in #zkl
Task
"Simulate" a four-bit adder.
This design can be realized using four 1-bit full adders.
Each of these 1-bit full adders can be built with two half adders and an or gate. ;
Finally a half adder can be made using an xor gate and an and gate.
The xor gate can be made us... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Roots_of_a_function | Roots of a function | Task
Create a program that finds and outputs the roots of a given function, range and (if applicable) step width.
The program should identify whether the root is exact or approximate.
For this task, use: ƒ(x) = x3 - 3x2 + 2x
| #Ada | Ada | with Ada.Text_Io; use Ada.Text_Io;
procedure Roots_Of_Function is
package Real_Io is new Ada.Text_Io.Float_Io(Long_Float);
use Real_Io;
function F(X : Long_Float) return Long_Float is
begin
return (X**3 - 3.0*X*X + 2.0*X);
end F;
Step : constant Long_Float := 1.0E-6;
Start : constant L... | Give a code snippet in #Ada
Task
Create a program that finds and outputs the roots of a given function, range and (if applicable) step width.
The program should identify whether the root is exact or approximate.
For this task, use: ƒ(x) = x3 - 3x2 + 2x
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Imaginary_base_numbers | Imaginary base numbers | Imaginary base numbers are a non-standard positional numeral system which uses an imaginary number as its radix. The most common is quater-imaginary with radix 2i.
The quater-imaginary numeral system was first proposed by Donald Knuth in 1955 as a submission for a high school science talent search. [Ref.]
Other imagi... | #Julia | Julia | import Base.show, Base.parse, Base.+, Base.-, Base.*, Base./, Base.^
function inbase4(charvec::Vector)
if (!all(x -> x in ['-', '0', '1', '2', '3', '.'], charvec)) ||
((x = findlast(x -> x == '-', charvec)) != nothing && x > findfirst(x -> x != '-', charvec)) ||
((x = findall(x -> x == '.', charve... | Give a code snippet in #Julia
Imaginary base numbers are a non-standard positional numeral system which uses an imaginary number as its radix. The most common is quater-imaginary with radix 2i.
The quater-imaginary numeral system was first proposed by Donald Knuth in 1955 as a submission for a high school science tal... | christopher/rosetta-code | |
http://rosettacode.org/wiki/4-rings_or_4-squares_puzzle | 4-rings or 4-squares puzzle | 4-rings or 4-squares puzzle
You are encouraged to solve this task according to the task description, using any language you may know.
Task
Replace a, b, c, d, e, f, and
g with the decimal
digits LOW ───► HIGH
such that the sum of the letters inside of each of the four large squares add up to
t... | #F.23 | F# |
(* A simple function to generate the sequence
Nigel Galloway: January 31st., 2017 *)
type G = {d:int;x:int;b:int;f:int}
let N n g =
{(max (n-g) n) .. (min (g-n) g)} |> Seq.collect(fun d->{(max (d+n+n) (n+n))..(min (g+g) (d+g+g))} |> Seq.collect(fun x ->
seq{for a in n .. g do for b in n .. g do if ... | Give a code snippet in #F.23
4-rings or 4-squares puzzle
You are encouraged to solve this task according to the task description, using any language you may know.
Task
Replace a, b, c, d, e, f, and
g with the decimal
digits LOW ───► HIGH
such that the sum of the letters inside of each of the ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sierpinski_arrowhead_curve | Sierpinski arrowhead curve | Task
Produce a graphical or ASCII-art representation of a Sierpinski arrowhead curve of at least order 3.
| #Go | Go | package main
import (
"github.com/fogleman/gg"
"math"
)
var (
width = 770.0
height = 770.0
dc = gg.NewContext(int(width), int(height))
iy = 1.0
theta = 0
)
var cx, cy, h float64
func arrowhead(order int, length float64) {
// if order is even, we can just draw the curve
... | Give a code snippet in #Go
Task
Produce a graphical or ASCII-art representation of a Sierpinski arrowhead curve of at least order 3.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Repeat_a_string | Repeat a string | Take a string and repeat it some number of times.
Example: repeat("ha", 5) => "hahahahaha"
If there is a simpler/more efficient way to repeat a single “character” (i.e. creating a string filled with a certain character), you might want to show that as well (i.e. repeat-char("*", 5) => "*****").
Other tasks re... | #Tosh | Tosh | when flag clicked
set String to "meow"
set Count to 4
set Repeated to ""
repeat Count
set Repeated to (join (Repeated) (String))
end
stop this script | Give a code snippet in #Tosh
Take a string and repeat it some number of times.
Example: repeat("ha", 5) => "hahahahaha"
If there is a simpler/more efficient way to repeat a single “character” (i.e. creating a string filled with a certain character), you might want to show that as well (i.e. repeat-char("*", 5) =... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Guess_the_number/With_feedback | Guess the number/With feedback | Task
Write a game (computer program) that follows the following rules:
The computer chooses a number between given set limits.
The player is asked for repeated guesses until the the target number is guessed correctly
At each guess, the computer responds with whether the guess is:
higher than the target,
equal to... | #D | D | import std.stdio, std.random, std.typecons, std.conv, std.string,
std.range;
void main() {
immutable interval = tuple(1, 100);
writefln("Guess my target number that is between " ~
"%d and %d (inclusive).\n", interval[]);
immutable target = uniform!"[]"(interval[]);
foreach (immut... | Give a code snippet in #D
Task
Write a game (computer program) that follows the following rules:
The computer chooses a number between given set limits.
The player is asked for repeated guesses until the the target number is guessed correctly
At each guess, the computer responds with whether the guess is:
higher... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sort_stability | Sort stability |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
... | #COBOL | COBOL | cities = [ {"UK", "London"},
{"US", "New York"},
{"US", "Birmingham"},
{"UK", "Birmingham"} ]
IO.inspect Enum.sort(cities)
IO.inspect Enum.sort(cities, fn a,b -> elem(a,0) >= elem(b,0) end)
IO.inspect Enum.sort_by(cities, fn {country, _city} -> country end)
IO.inspect Enum.sort_by(cit... | Give a code snippet in #COBOL
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick so... | christopher/rosetta-code |
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.