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/Matrix_transposition | Matrix transposition | Transpose an arbitrarily sized rectangular Matrix.
| #Racket | Racket |
#lang racket
(require math)
(matrix-transpose (matrix [[1 2] [3 4]]))
| Give a code snippet in #Racket
Transpose an arbitrarily sized rectangular Matrix.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Compare_a_list_of_strings | Compare a list of strings | Task
Given a list of arbitrarily many strings, show how to:
test if they are all lexically equal
test if every string is lexically less than the one after it (i.e. whether the list is in strict ascending order)
Each of those two tests should result in a single true or false value, which could be used as t... | #Fortran | Fortran |
INTEGER MANY,LONG
PARAMETER (LONG = 6,MANY = 4) !Adjust to suit.
CHARACTER*(LONG) STRINGS(MANY) !A list of text strings.
STRINGS(1) = "Fee"
STRINGS(2) = "Fie"
STRINGS(3) = "Foe"
STRINGS(4) = "Fum"
IF (ALL(STRINGS(1:MANY - 1) .LT. STRINGS(2:MANY))) THEN
WRITE (6,... | Give a code snippet in #Fortran
Task
Given a list of arbitrarily many strings, show how to:
test if they are all lexically equal
test if every string is lexically less than the one after it (i.e. whether the list is in strict ascending order)
Each of those two tests should result in a single true or fals... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Documentation | Documentation |
See also
Related task: Comments
Related task: Here_document
| #PARI.2FGP | PARI/GP | addhelp(funcName, "funcName(v, n): This is a description of the function named funcName."); | Give a code snippet in #PARI.2FGP
See also
Related task: Comments
Related task: Here_document
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Calculating_the_value_of_e | Calculating the value of e | Task
Calculate the value of e.
(e is also known as Euler's number and Napier's constant.)
See details: Calculating the value of e
| #ALGOL_68 | ALGOL 68 | BEGIN
# calculate an approximation to e #
LONG REAL epsilon = 1.0e-15;
LONG INT fact := 1;
LONG REAL e := 2;
LONG INT n := 2;
WHILE
LONG REAL e0 = e;
fact *:= n;
n +:= 1;
e +:= 1.0 / fact;
ABS ( e - e0 ) >= epsilon
DO SKIP OD;
p... | Give a code snippet in #ALGOL_68
Task
Calculate the value of e.
(e is also known as Euler's number and Napier's constant.)
See details: Calculating the value of e
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Search_a_list_of_records | Search a list of records | Many programming languages provide convenient ways to look for a known value in a simple list of strings or numbers.
But what if the elements of the list are themselves compound records/objects/data-structures, and the search condition is more complex than a simple equality test?
Task[edit]
Write a function/method/et... | #Perl | Perl | use feature 'say';
use List::Util qw(first);
my @cities = (
{ name => 'Lagos', population => 21.0 },
{ name => 'Cairo', population => 15.2 },
{ name => 'Kinshasa-Brazzaville', population => 11.3 },
{ name => 'Greater Johannesburg', population => 7.55 },
{ name => 'Mogadishu... | Give a code snippet in #Perl
Many programming languages provide convenient ways to look for a known value in a simple list of strings or numbers.
But what if the elements of the list are themselves compound records/objects/data-structures, and the search condition is more complex than a simple equality test?
Task[ed... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Jewels_and_stones | Jewels and stones | Jewels and stones
You are encouraged to solve this task according to the task description, using any language you may know.
Task
Create a function which takes two string parameters: 'stones' and 'jewels' and returns an integer.
Both strings can contain any number of upper or lower case letters. However, in the case ... | #AppleScript | AppleScript | -- jewelCount :: String -> String -> Int
on jewelCount(jewels, stones)
set js to chars(jewels)
script
on |λ|(a, c)
if elem(c, jewels) then
a + 1
else
a
end if
end |λ|
end script
foldl(result, 0, chars(stones))
end jewelC... | Give a code snippet in #AppleScript
Jewels and stones
You are encouraged to solve this task according to the task description, using any language you may know.
Task
Create a function which takes two string parameters: 'stones' and 'jewels' and returns an integer.
Both strings can contain any number of upper or lowe... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Zig-zag_matrix | Zig-zag matrix | Task
Produce a zig-zag array.
A zig-zag array is a square arrangement of the first N2 natural numbers, where the
numbers increase sequentially as you zig-zag along the array's anti-diagonals.
For a graphical representation, see JPG zigzag (JPG uses such arrays to encode images).
For example, gi... | #Clojure | Clojure | (defn partitions [sizes coll]
(lazy-seq
(when-let [n (first sizes)]
(when-let [s (seq coll)]
(cons (take n coll)
(partitions (next sizes) (drop n coll)))))))
(defn take-from [n colls]
(lazy-seq
(when-let [s (seq colls)]
(let [[first-n rest-n] (split-at n s)]
(cons (map first fi... | Give a code snippet in #Clojure
Task
Produce a zig-zag array.
A zig-zag array is a square arrangement of the first N2 natural numbers, where the
numbers increase sequentially as you zig-zag along the array's anti-diagonals.
For a graphical representation, see JPG zigzag (JPG uses such arrays to e... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Motzkin_numbers | Motzkin numbers | Definition
The nth Motzkin number (denoted by M[n]) is the number of different ways of drawing non-intersecting chords between n points on a circle (not necessarily touching every point by a chord).
By convention M[0] = 1.
Task
Compute and show on this page the first 42 Motzkin numbers or, if your language does not... | #Burlesque | Burlesque | 41rz{{2./}c!rz2?*{nr}c!\/2?/{JJ2.*J#Rnr#r\/+.nr.-}m[?*++it+.}m[Jp^#R{~]}5E!{fCL[1==}f[#r | Give a code snippet in #Burlesque
Definition
The nth Motzkin number (denoted by M[n]) is the number of different ways of drawing non-intersecting chords between n points on a circle (not necessarily touching every point by a chord).
By convention M[0] = 1.
Task
Compute and show on this page the first 42 Motzkin nu... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Binary_strings | Binary strings | Many languages have powerful and useful (binary safe) string manipulation functions, while others don't, making it harder for these languages to accomplish some tasks.
This task is about creating functions to handle binary strings (strings made of arbitrary bytes, i.e. byte strings according to Wikipedia) for those la... | #E | E | ? def int8 := <type:java.lang.Byte>
# value: int8 | Give a code snippet in #E
Many languages have powerful and useful (binary safe) string manipulation functions, while others don't, making it harder for these languages to accomplish some tasks.
This task is about creating functions to handle binary strings (strings made of arbitrary bytes, i.e. byte strings according... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Horizontal_sundial_calculations | Horizontal sundial calculations | Task
Create a program that calculates the hour, sun hour angle, dial hour line angle from 6am to 6pm for an operator entered location.
For example, the user is prompted for a location and inputs the latitude and longitude 4°57′S 150°30′W (4.95°S 150.5°W of Jules Verne's Lincoln Island, aka Ernest Legouve Reef), wit... | #F.23 | F# | // Learn more about F# at http://fsharp.net
open System
//(degree measure)*Degrees => Radian measure
//(radian measure)/Degrees => Degree measure
let Degrees = Math.PI / 180.0
Console.Write("Enter latitude: ")
let latitude = Console.ReadLine() |> Double.Parse
Console.Write("Enter longitude: ")
let longitude = C... | Give a code snippet in #F.23
Task
Create a program that calculates the hour, sun hour angle, dial hour line angle from 6am to 6pm for an operator entered location.
For example, the user is prompted for a location and inputs the latitude and longitude 4°57′S 150°30′W (4.95°S 150.5°W of Jules Verne's Lincoln Island,... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Table_creation/Postal_addresses | Table creation/Postal addresses | Task
Create a table to store addresses.
You may assume that all the addresses to be stored will be located in the USA. As such, you will need (in addition to a field holding a unique identifier) a field holding the street address, a field holding the city, a field holding the state code, and a field holding the zip... | #Nim | Nim | import db_sqlite as db
#import db_mysql as db
#import db_postgres as db
const
connection = ":memory:"
user = "foo"
pass = "bar"
database = "db"
var c = open(connection, user, pass, database)
c.exec sql"""CREATE TABLE address (
addrID INTEGER PRIMARY KEY AUTOINCREMENT,
addrStreet TEXT NOT NULL,
add... | Give a code snippet in #Nim
Task
Create a table to store addresses.
You may assume that all the addresses to be stored will be located in the USA. As such, you will need (in addition to a field holding a unique identifier) a field holding the street address, a field holding the city, a field holding the state code... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Wilson_primes_of_order_n | Wilson primes of order n | Definition
A Wilson prime of order n is a prime number p such that p2 exactly divides:
(n − 1)! × (p − n)! − (− 1)n
If n is 1, the latter formula reduces to the more familiar: (p - n)! + 1 where the only known examples for p are 5, 13, and 563.
Task
Calculate and show on thi... | #Prolog | Prolog | main:-
wilson_primes(11000).
wilson_primes(Limit):-
writeln(' n | Wilson primes\n---------------------'),
make_factorials(Limit),
find_prime_numbers(Limit),
wilson_primes(1, 12, -1).
wilson_primes(N, N, _):-!.
wilson_primes(N, M, S):-
wilson_primes(N, S),
S1 is -S,
N1 is N + 1,
... | Give a code snippet in #Prolog
Definition
A Wilson prime of order n is a prime number p such that p2 exactly divides:
(n − 1)! × (p − n)! − (− 1)n
If n is 1, the latter formula reduces to the more familiar: (p - n)! + 1 where the only known examples for p are 5, 13, and 563.
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Chinese_remainder_theorem | Chinese remainder theorem | Suppose
n
1
{\displaystyle n_{1}}
,
n
2
{\displaystyle n_{2}}
,
…
{\displaystyle \ldots }
,
n
k
{\displaystyle n_{k}}
are positive integers that are pairwise co-prime.
Then, for any given sequence of integers
a
1
{\displaystyle a_{1}}
,
a
2
... | #F.23 | F# | let rec sieve cs x N =
match cs with
| [] -> Some(x)
| (a,n)::rest ->
let arrProgress = Seq.unfold (fun x -> Some(x, x+N)) x
let firstXmodNequalA = Seq.tryFind (fun x -> a = x % n)
match firstXmodNequalA (Seq.take n arrProgress) with
| None -> None
| Some(x) -> sieve ... | Give a code snippet in #F.23
Suppose
n
1
{\displaystyle n_{1}}
,
n
2
{\displaystyle n_{2}}
,
…
{\displaystyle \ldots }
,
n
k
{\displaystyle n_{k}}
are positive integers that are pairwise co-prime.
Then, for any given sequence of integers
a
1
{\displayst... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Detect_division_by_zero | Detect division by zero | Task
Write a function to detect a divide by zero error without checking if the denominator is zero.
| #Java | Java | public static boolean infinity(double numer, double denom){
return Double.isInfinite(numer/denom);
} | Give a code snippet in #Java
Task
Write a function to detect a divide by zero error without checking if the denominator is zero.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Number_reversal_game | Number reversal game | Task
Given a jumbled list of the numbers 1 to 9 that are definitely not in
ascending order.
Show the list, and then ask the player how many digits from the
left to reverse.
Reverse those digits, then ask again, until all the digits end up in ascending order.
The score is the count of the reversa... | #jq | jq | # Input: the initial array
def play:
def sorted: . == sort;
def reverse(n): (.[0:n] | reverse) + .[n:];
def prompt: "List: \(.list)\nEnter a pivot number: ";
def report: "Great! Your score is \(.score)";
{list: ., score: 0}
| (if .list | sorted then "List was sorted to begin with."
else
... | Give a code snippet in #jq
Task
Given a jumbled list of the numbers 1 to 9 that are definitely not in
ascending order.
Show the list, and then ask the player how many digits from the
left to reverse.
Reverse those digits, then ask again, until all the digits end up in ascending order.
The score... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sierpinski_carpet | Sierpinski carpet | Task
Produce a graphical or ASCII-art representation of a Sierpinski carpet of order N.
For example, the Sierpinski carpet of order 3 should look like this:
###########################
# ## ## ## ## ## ## ## ## #
###########################
### ###### ###### ###
# # # ## # # ## # # #
### ###### ... | #jq | jq |
def inCarpet(x; y):
x as $x | y as $y |
if $x == -1 or $y == -1 then "\n"
elif $x == 0 or $y == 0 then "*"
elif ($x % 3) == 1 and ($y % 3) == 1 then " "
else inCarpet($x/3 | floor; $y/3 | floor)
end;
def ipow(n):
. as $in | reduce range(0;n) as $i (1; . * $in);
def carpet(n):
(3|ipow(n)) as $powe... | Give a code snippet in #jq
Task
Produce a graphical or ASCII-art representation of a Sierpinski carpet of order N.
For example, the Sierpinski carpet of order 3 should look like this:
###########################
# ## ## ## ## ## ## ## ## #
###########################
### ###### ###### ###
# # # ## # ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Non-decimal_radices/Input | Non-decimal radices/Input | It is common to have a string containing a number written in some format, with the most common ones being decimal, hexadecimal, octal and binary. Such strings are found in many places (user interfaces, configuration files, XML data, network protocols, etc.)
This task requires parsing of such a string (which may be ass... | #Icon_and_Unicon | Icon and Unicon |
procedure convert (str)
write (left(str, 10) || " = " || integer(str))
end
procedure main ()
convert (" 2r1001")
convert (" 8r7135")
convert ("16rABC1234")
convert ("36r1Z")
write ("2r1001" + "36r1Z") # shows type conversion, string->integer
end
| Give a code snippet in #Icon_and_Unicon
It is common to have a string containing a number written in some format, with the most common ones being decimal, hexadecimal, octal and binary. Such strings are found in many places (user interfaces, configuration files, XML data, network protocols, etc.)
This task requires p... | christopher/rosetta-code | |
http://rosettacode.org/wiki/URL_decoding | URL decoding | This task (the reverse of URL encoding and distinct from URL parser) is to provide a function
or mechanism to convert an URL-encoded string into its original unencoded form.
Test cases
The encoded string "http%3A%2F%2Ffoo%20bar%2F" should be reverted to the unencoded form "http://foo bar/".
Th... | #Objective-C | Objective-C | NSString *encoded = @"http%3A%2F%2Ffoo%20bar%2F";
NSString *normal = [encoded stringByReplacingPercentEscapesUsingEncoding:NSUTF8StringEncoding];
NSLog(@"%@", normal); | Give a code snippet in #Objective-C
This task (the reverse of URL encoding and distinct from URL parser) is to provide a function
or mechanism to convert an URL-encoded string into its original unencoded form.
Test cases
The encoded string "http%3A%2F%2Ffoo%20bar%2F" should be reverted to the unen... | christopher/rosetta-code | |
http://rosettacode.org/wiki/99_bottles_of_beer | 99 bottles of beer | Task
Display the complete lyrics for the song: 99 Bottles of Beer on the Wall.
The beer song
The lyrics follow this form:
99 bottles of beer on the wall
99 bottles of beer
Take one down, pass it around
98 bottles of beer on the wall
98 bottles of beer on the wall
98 bottles of beer
Take one dow... | #CLIPS | CLIPS | (deffacts beer-bottles
(bottles 99))
(deffunction bottle-count
(?count)
(switch ?count
(case 0 then "No more bottles of beer")
(case 1 then "1 more bottle of beer")
(default (str-cat ?count " bottles of beer"))))
(defrule stanza
?bottles <- (bottles ?count)
=>
(retract ?bottles)
(printout ... | Give a code snippet in #CLIPS
Task
Display the complete lyrics for the song: 99 Bottles of Beer on the Wall.
The beer song
The lyrics follow this form:
99 bottles of beer on the wall
99 bottles of beer
Take one down, pass it around
98 bottles of beer on the wall
98 bottles of beer on the wall
98... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Set | Set |
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.
A set is a collection of elements, without duplicates and without order.
Task
Show each of these set operations:
Set creation
Test m ∈ S -- "m is an... | #Nemerle | Nemerle | using System.Console;
using Nemerle.Collections;
module RCSet
{
HasSubset[T](this super : Set[T], sub : Set[T]) : bool
{
super.ForAll(x => sub.Contains(x))
}
Main() : void
{
def names1 = Set(["Bob", "Billy", "Tom", "Dick", "Harry"]);
def names2 = Set(["Bob", "Mary", "Alic... | Give a code snippet in #Nemerle
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.
A set is a collection of elements, without duplicates and without order.
Task
Show each of these set operations:
Set... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Cumulative_standard_deviation | Cumulative standard deviation | Task[edit]
Write a stateful function, class, generator or co-routine that takes a series of floating point numbers, one at a time, and returns the running standard deviation of the series.
The task implementation should use the most natural programming style of those listed for the function in the implementation langu... | #Go | Go | package main
import (
"fmt"
"math"
)
func newRsdv() func(float64) float64 {
var n, a, q float64
return func(x float64) float64 {
n++
a1 := a+(x-a)/n
q, a = q+(x-a)*(x-a1), a1
return math.Sqrt(q/n)
}
}
func main() {
r := newRsdv()
for _, x := range []flo... | Give a code snippet in #Go
Task[edit]
Write a stateful function, class, generator or co-routine that takes a series of floating point numbers, one at a time, and returns the running standard deviation of the series.
The task implementation should use the most natural programming style of those listed for the function... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Associative_array/Iteration | Associative array/Iteration | Show how to iterate over the key-value pairs of an associative array, and print each pair out.
Also show how to iterate just over the keys, or the values, if there is a separate way to do that in your language.
See also
Array
Associative array: Creation, Iteration
Collections
Compound data type
Doubly-linked ... | #LiveCode | LiveCode | put 3 into fruit["apples"]
put 5 into fruit["pears"]
put 6 into fruit["oranges"]
put "none" into fruit["bananas"]
put "Keys:" & cr & the keys of fruit & cr into tTmp
put "Values 1:" & tab after tTmp
repeat for each line tKey in the keys of fruit
put fruit[tkey] & comma after tTmp
end repeat
-- need to copy arra... | Give a code snippet in #LiveCode
Show how to iterate over the key-value pairs of an associative array, and print each pair out.
Also show how to iterate just over the keys, or the values, if there is a separate way to do that in your language.
See also
Array
Associative array: Creation, Iteration
Collections
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sequence_of_primes_by_trial_division | Sequence of primes by trial division | Sequence of primes by trial division
You are encouraged to solve this task according to the task description, using any language you may know.
Task
Generate a sequence of primes by means of trial division.
Trial division is an algorithm where a candidate number is tested for being a prime by trying to divide it by... | #Rust | Rust |
fn is_prime(number: u32) -> bool {
#[allow(clippy::cast_precision_loss)]
let limit = (number as f32).sqrt() as u32 + 1;
// We test if the number is divisible by any number up to the limit
!(number < 2 || (2..limit).any(|x| number % x == 0))
}
fn main() {
println!(
"Primes below 100:\n{... | Give a code snippet in #Rust
Sequence of primes by trial division
You are encouraged to solve this task according to the task description, using any language you may know.
Task
Generate a sequence of primes by means of trial division.
Trial division is an algorithm where a candidate number is tested for being a p... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Statistics/Normal_distribution | Statistics/Normal distribution | The Normal (or Gaussian) distribution is a frequently used distribution in statistics. While most programming languages provide a uniformly distributed random number generator, one can derive normally distributed random numbers from a uniform generator.
The task
Take a uniform random number generator and create a ... | #VBA | VBA | Public Sub standard_normal()
Dim s() As Variant, bins(71) As Single
ReDim s(20000)
For i = 1 To 20000
s(i) = WorksheetFunction.Norm_S_Inv(Rnd())
Next i
For i = -35 To 35
bins(i + 36) = i / 10
Next i
Debug.Print "sample size"; UBound(s), "mean"; mean(s), "standard deviation"; ... | Give a code snippet in #VBA
The Normal (or Gaussian) distribution is a frequently used distribution in statistics. While most programming languages provide a uniformly distributed random number generator, one can derive normally distributed random numbers from a uniform generator.
The task
Take a uniform random n... | christopher/rosetta-code | |
http://rosettacode.org/wiki/SHA-1 | SHA-1 | SHA-1 or SHA1 is a one-way hash function;
it computes a 160-bit message digest.
SHA-1 often appears in security protocols; for example,
many HTTPS websites use RSA with SHA-1 to secure their connections.
BitTorrent uses SHA-1 to verify downloads.
Git and Mercurial use SHA-1 digests to identify commits.
A US government... | #Crystal | Crystal | require "openssl"
puts OpenSSL::Digest.new("sha1").update("Rosetta Code") | Give a code snippet in #Crystal
SHA-1 or SHA1 is a one-way hash function;
it computes a 160-bit message digest.
SHA-1 often appears in security protocols; for example,
many HTTPS websites use RSA with SHA-1 to secure their connections.
BitTorrent uses SHA-1 to verify downloads.
Git and Mercurial use SHA-1 digests to i... | christopher/rosetta-code | |
http://rosettacode.org/wiki/99_bottles_of_beer | 99 bottles of beer | Task
Display the complete lyrics for the song: 99 Bottles of Beer on the Wall.
The beer song
The lyrics follow this form:
99 bottles of beer on the wall
99 bottles of beer
Take one down, pass it around
98 bottles of beer on the wall
98 bottles of beer on the wall
98 bottles of beer
Take one dow... | #FOCAL | FOCAL | 01.10 S N=99
01.15 D 2;T " OF BEER ON THE WALL,",!
01.20 D 2;T " OF BEER,",!
01.24 S N=N-1
01.25 T "TAKE ";I (N),1.3,1.4,1.3
01.30 T "IT";G 1.5
01.40 T "ONE"
01.50 T " DOWN AND PASS IT AROUND,",!
01.60 D 2;T " OF BEER ON THE WALL!",!!
01.70 I (N),1.8,1.15
01.80 Q
02.01 C-PRINT N BOTTLE(S)
02.10 I (N)2.2,2.2,2.3
02.20... | Give a code snippet in #FOCAL
Task
Display the complete lyrics for the song: 99 Bottles of Beer on the Wall.
The beer song
The lyrics follow this form:
99 bottles of beer on the wall
99 bottles of beer
Take one down, pass it around
98 bottles of beer on the wall
98 bottles of beer on the wall
98... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Faces_from_a_mesh | Faces from a mesh | A mesh defining a surface has uniquely numbered vertices, and named,
simple-polygonal faces described usually by an ordered list of edge numbers
going around the face,
For example:
External image of two faces
Rough textual version without edges:
1
17
7 A
B
... | #Python | Python | def perim_equal(p1, p2):
# Cheap tests first
if len(p1) != len(p2) or set(p1) != set(p2):
return False
if any(p2 == (p1[n:] + p1[:n]) for n in range(len(p1))):
return True
p2 = p2[::-1] # not inplace
return any(p2 == (p1[n:] + p1[:n]) for n in range(len(p1)))
def edge_to_periphery(... | Give a code snippet in #Python
A mesh defining a surface has uniquely numbered vertices, and named,
simple-polygonal faces described usually by an ordered list of edge numbers
going around the face,
For example:
External image of two faces
Rough textual version without edges:
1
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Higher-order_functions | Higher-order functions | Task
Pass a function as an argument to another function.
Related task
First-class functions
| #GAP | GAP | Eval := function(f, x)
return f(x);
end;
Eval(x -> x^3, 7);
# 343 | Give a code snippet in #GAP
Task
Pass a function as an argument to another function.
Related task
First-class functions
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Create_a_file | Create a file | In this task, the job is to create a new empty file called "output.txt" of size 0 bytes
and an empty directory called "docs". This should be done twice: once "here", i.e. in the current working directory and once in the filesystem root.
| #Blue | Blue | global _start
: syscall ( num:eax -- result:eax ) syscall ;
: exit ( status:edi -- noret ) 60 syscall ;
: bye ( -- noret ) 0 exit ;
: die ( err:eax -- noret ) neg exit ;
: unwrap ( result:eax -- value:eax ) dup 0 cmp ' die xl ;
: ordie ( result -- ) unwrap drop ;
: open ( pathname:edi flags:esi mode:edx -- fd:e... | Give a code snippet in #Blue
In this task, the job is to create a new empty file called "output.txt" of size 0 bytes
and an empty directory called "docs". This should be done twice: once "here", i.e. in the current working directory and once in the filesystem root.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Sorting_algorithms/Bogosort | Sorting algorithms/Bogosort |
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
... | #BBC_BASIC | BBC BASIC | DIM test(9)
test() = 4, 65, 2, 31, 0, 99, 2, 83, 782, 1
shuffles% = 0
WHILE NOT FNsorted(test())
shuffles% += 1
PROCshuffle(test())
ENDWHILE
PRINT ;shuffles% " shuffles required to sort "; DIM(test(),1)+1 " items."
END
DEF PROCshuffle(d())
LOCAL ... | Give a code snippet in #BBC_BASIC
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 |
Quic... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Strip_control_codes_and_extended_characters_from_a_string | Strip control codes and extended characters from a string | Task
Strip control codes and extended characters from a string.
The solution should demonstrate how to achieve each of the following results:
a string with control codes stripped (but extended characters not stripped)
a string with control codes and extended characters stripped
In ASCII, the control codes ... | #JavaScript | JavaScript | (function (strTest) {
// s -> s
function strip(s) {
return s.split('').filter(function (x) {
var n = x.charCodeAt(0);
return 31 < n && 127 > n;
}).join('');
}
return strip(strTest);
})("\ba\x00b\n\rc\fd\xc3"); | Give a code snippet in #JavaScript
Task
Strip control codes and extended characters from a string.
The solution should demonstrate how to achieve each of the following results:
a string with control codes stripped (but extended characters not stripped)
a string with control codes and extended characters str... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Write_float_arrays_to_a_text_file | Write float arrays to a text file | Task
Write two equal-sized numerical arrays 'x' and 'y' to
a two-column text file named 'filename'.
The first column of the file contains values from an 'x'-array with a
given 'xprecision', the second -- values from 'y'-array with 'yprecision'.
For example, considering:
x = {1, 2, 3, 1e11};
y = {1, 1.41421356... | #Phix | Phix | constant x = {1, 2, 3, 1e11},
y = {1, 1.4142135623730951, 1.7320508075688772, 316227.76601683791}
integer fn = open("filename","w")
for i=1 to length(x) do
printf(fn,"%.3g\t%.5g\n",{x[i],y[i]})
end for
close(fn)
| Give a code snippet in #Phix
Task
Write two equal-sized numerical arrays 'x' and 'y' to
a two-column text file named 'filename'.
The first column of the file contains values from an 'x'-array with a
given 'xprecision', the second -- values from 'y'-array with 'yprecision'.
For example, considering:
x = {1, 2, 3... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Modular_inverse | Modular inverse | From Wikipedia:
In modular arithmetic, the modular multiplicative inverse of an integer a modulo m is an integer x such that
a
x
≡
1
(
mod
m
)
.
{\displaystyle a\,x\equiv 1{\pmod {m}}.}
Or in other words, such that:
∃
k
∈
Z
,
a
x
=
1
+
k
m
{\displaystyle \exists k\in \math... | #Delphi | Delphi | proc mulinv(int a, b) int:
int t, nt, r, nr, q, tmp;
if b<0 then b := -b fi;
if a<0 then a := b - (-a % b) fi;
t := 0; nt := 1; r := b; nr := a % b;
while nr /= 0 do
q := r / nr;
tmp := nt; nt := t - q*nt; t := tmp;
tmp := nr; nr := r - q*nr; r := tmp
od;
if r>1 then ... | Give a code snippet in #Delphi
From Wikipedia:
In modular arithmetic, the modular multiplicative inverse of an integer a modulo m is an integer x such that
a
x
≡
1
(
mod
m
)
.
{\displaystyle a\,x\equiv 1{\pmod {m}}.}
Or in other words, such that:
∃
k
∈
Z
,
a
x
=
1
+
k
m
{... | christopher/rosetta-code | |
http://rosettacode.org/wiki/String_prepend | String prepend |
Basic Data Operation
This is a basic data operation. It represents a fundamental action on a basic data type.
You may see other such operations in the Basic Data Operations category, or:
Integer Operations
Arithmetic |
Comparison
Boolean Operations
Bitwise |
Logical
String Operations
Concatenation |
Interpolation |... | #C.2B.2B | C++ | include <vector>
#include <algorithm>
#include <string>
#include <iostream>
int main( ) {
std::vector<std::string> myStrings { "prepended to" , "my string" } ;
std::string prepended = std::accumulate( myStrings.begin( ) ,
myStrings.end( ) , std::string( "" ) , []( std::string a ,
std::string b ) { retu... | Give a code snippet in #C.2B.2B
Basic Data Operation
This is a basic data operation. It represents a fundamental action on a basic data type.
You may see other such operations in the Basic Data Operations category, or:
Integer Operations
Arithmetic |
Comparison
Boolean Operations
Bitwise |
Logical
String Operation... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Speech_synthesis | Speech synthesis | Render the text This is an example of speech synthesis as speech.
Related task
using a speech engine to highlight words
| #Ring_2 | Ring |
load "guilib.ring"
load "stdlib.ring"
MyApp = New qApp {
win1 = new qWidget() {
setwindowtitle("Hello World")
setGeometry(100,100,370,250)
Text = "This is an example of speech synthesis"
Text = split(Text," ")
label1 = n... | Give a code snippet in #Ring_2
Render the text This is an example of speech synthesis as speech.
Related task
using a speech engine to highlight words
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Hello_world/Newline_omission | Hello world/Newline omission | Some languages automatically insert a newline after outputting a string, unless measures are taken to prevent its output.
Task
Display the string Goodbye, World! without a trailing newline.
Related tasks
Hello world/Graphical
Hello world/Line Printer
Hello world/Standard error
Hello world/Text
| #IWBASIC | IWBASIC |
'In a window
DEF Win:WINDOW
DEF Close:CHAR
DEF ScreenSizeX,ScreenSizeY:UINT
GETSCREENSIZE(ScreenSizeX,ScreenSizeY)
OPENWINDOW Win,0,0,ScreenSizeX,ScreenSizeY,NULL,NULL,"Goodbye program",&MainHandler
PRINT Win,"Goodbye, World!"
'Prints in upper left corner of the window (position 0,0).
PRINT Win," You won't ha... | Give a code snippet in #IWBASIC
Some languages automatically insert a newline after outputting a string, unless measures are taken to prevent its output.
Task
Display the string Goodbye, World! without a trailing newline.
Related tasks
Hello world/Graphical
Hello world/Line Printer
Hello world/Sta... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Averages/Mode | Averages/Mode | Task[edit]
Write a program to find the mode value of a collection.
The case where the collection is empty may be ignored. Care must be taken to handle the case where the mode is non-unique.
If it is not appropriate or possible to support a general collection, use a vector (array), if possible. If it is not appropriat... | #zkl | zkl | fcn mode(items){
d:=Dictionary(); foreach i in (items){ d.incV(i) }
m:=d.reduce(fcn(m,[(_,v)]){ v.max(m) },0);
d.filter('wrap([(_,v)]){ v==m }).apply("get",0);
} | Give a code snippet in #zkl
Task[edit]
Write a program to find the mode value of a collection.
The case where the collection is empty may be ignored. Care must be taken to handle the case where the mode is non-unique.
If it is not appropriate or possible to support a general collection, use a vector (array), if poss... | 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... | #11l | 11l | F factorial(n)
V result = 1
L(i) 2..n
result *= i
R result
L(n) 0..5
print(n‘ ’factorial(n)) | Give a code snippet in #11l
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 num... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Almost_prime | Almost prime | A k-Almost-prime is a natural number
n
{\displaystyle n}
that is the product of
k
{\displaystyle k}
(possibly identical) primes.
Example
1-almost-primes, where
k
=
1
{\displaystyle k=1}
, are the prime numbers themselves.
2-almost-primes, where
k
=
2
{\displaystyl... | #Clojure | Clojure |
(ns clojure.examples.almostprime
(:gen-class))
(defn divisors [n]
" Finds divisors by looping through integers 2, 3,...i.. up to sqrt (n) [note: rather than compute sqrt(), test with i*i <=n] "
(let [div (some #(if (= 0 (mod n %)) % nil) (take-while #(<= (* % %) n) (iterate inc 2)))]
(if div ... | Give a code snippet in #Clojure
A k-Almost-prime is a natural number
n
{\displaystyle n}
that is the product of
k
{\displaystyle k}
(possibly identical) primes.
Example
1-almost-primes, where
k
=
1
{\displaystyle k=1}
, are the prime numbers themselves.
2-almost-primes, ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Forward_difference | Forward difference | Task
Provide code that produces a list of numbers which is the nth order forward difference, given a non-negative integer (specifying the order) and a list of numbers.
The first-order forward difference of a list of numbers A is a new list B, where Bn = An+1 - An.
List B should have one fewer elem... | #zkl | zkl | fcn forwardDiff(lst){
if(lst.len()<2)
return(T);
return(T(lst[1]-lst[0]).extend(forwardDiff(lst[1,*])))
}
fcn nthForwardDiff(n,xs){
if(n==0)
return(xs);
return(nthForwardDiff(n-1,forwardDiff(xs))) // tail recursion
} | Give a code snippet in #zkl
Task
Provide code that produces a list of numbers which is the nth order forward difference, given a non-negative integer (specifying the order) and a list of numbers.
The first-order forward difference of a list of numbers A is a new list B, where Bn = An+1 - An.
List B... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Evaluate_binomial_coefficients | Evaluate binomial coefficients | This programming task, is to calculate ANY binomial coefficient.
However, it has to be able to output
(
5
3
)
{\displaystyle {\binom {5}{3}}}
, which is 10.
This formula is recommended:
(
n
k
)
=
n
!
(
n
−
k
)
!
k
!
=
n
(
n
−
1
)
(
n
−
2
)
…
(
n
−
k
+
1
)
k
(
k
−
1... | #BCPL | BCPL |
GET "libhdr"
LET choose(n, k) =
~(0 <= k <= n) -> 0,
2*k > n -> binomial(n, n - k),
binomial(n, k)
AND binomial(n, k) =
k = 0 -> 1,
binomial(n, k - 1) * (n - k + 1) / k
LET start() = VALOF {
LET n, k = ?, ?
LET argv = VEC 20
LET sz = ?
sz := rdargs("n/a/n/p,k/a/n/p", argv, 20)
UNLESS ... | Give a code snippet in #BCPL
This programming task, is to calculate ANY binomial coefficient.
However, it has to be able to output
(
5
3
)
{\displaystyle {\binom {5}{3}}}
, which is 10.
This formula is recommended:
(
n
k
)
=
n
!
(
n
−
k
)
!
k
!
=
n
(
n
−
1
)
(
n
−
2... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Align_columns | Align columns | Given a text file of many lines, where fields within a line
are delineated by a single 'dollar' character, write a program
that aligns each column of fields by ensuring that words in each
column are separated by at least one space.
Further, allow for each word in a column to be either left
justified, right justified, o... | #ML.2FI | ML/I | MCSKIP "WITH" NL
"" Align columns - assumes macros on input stream 1, data on stream 2
MCPVAR 102
"" Set P102 to alignment required:
"" 1 = centre
"" 2 = left
"" 3 = right
MCSET P102 = 1
MCSKIP MT,<>
MCINS %.
MCSKIP SL WITH *
"" Assume no more than 100 columns - P101 used for max number of fields
"" Set P variabl... | Give a code snippet in #ML.2FI
Given a text file of many lines, where fields within a line
are delineated by a single 'dollar' character, write a program
that aligns each column of fields by ensuring that words in each
column are separated by at least one space.
Further, allow for each word in a column to be either le... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Ordered_partitions | Ordered partitions | In this task we want to find the ordered partitions into fixed-size blocks.
This task is related to Combinations in that it has to do with discrete mathematics and moreover a helper function to compute combinations is (probably) needed to solve this task.
p
a
r
t
i
t
i
o
n
s
(
a
r
g
1
,
a
r
g
2
,
... | #Elixir | Elixir | defmodule Ordered do
def partition([]), do: [[]]
def partition(mask) do
sum = Enum.sum(mask)
if sum == 0 do
[Enum.map(mask, fn _ -> [] end)]
else
Enum.to_list(1..sum)
|> permute
|> Enum.reduce([], fn perm,acc ->
{_, part} = Enum.reduce(mask, {perm,[]}, fn num,{pm,a} -... | Give a code snippet in #Elixir
In this task we want to find the ordered partitions into fixed-size blocks.
This task is related to Combinations in that it has to do with discrete mathematics and moreover a helper function to compute combinations is (probably) needed to solve this task.
p
a
r
t
i
t
i
o
n
s
(
a... | christopher/rosetta-code | |
http://rosettacode.org/wiki/N%27th | N'th | Write a function/method/subroutine/... that when given an integer greater than or equal to zero returns a string of the number followed by an apostrophe then the ordinal suffix.
Example
Returns would include 1'st 2'nd 3'rd 11'th 111'th 1001'st 1012'th
Task
Use your routine to show here the output for at least t... | #F.23 | F# | open System
let ordinalsuffix n =
let suffixstrings = [|"th"; "st"; "nd"; "rd"|]
let (d, r) = Math.DivRem(n, 10)
n.ToString() + suffixstrings.[ if r < 4 && (d &&& 1) = 0 then r else 0 ]
[<EntryPoint>]
let main argv =
let show = (Seq.iter (ordinalsuffix >> (printf " %s"))) >> (Console.WriteLine)
... | Give a code snippet in #F.23
Write a function/method/subroutine/... that when given an integer greater than or equal to zero returns a string of the number followed by an apostrophe then the ordinal suffix.
Example
Returns would include 1'st 2'nd 3'rd 11'th 111'th 1001'st 1012'th
Task
Use your routine to show ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Classes | Classes | In object-oriented programming class is a set (a transitive closure) of types bound by the relation of inheritance. It is said that all types derived from some base type T and the type T itself form a class T.
The first type T from the class T sometimes is called the root type of the class.
A class of types itself, a... | #BBC_BASIC | BBC BASIC | INSTALL @lib$+"CLASSLIB"
REM Declare the class:
DIM MyClass{variable, @constructor, _method}
DEF MyClass.@constructor MyClass.variable = PI : ENDPROC
DEF MyClass._method = MyClass.variable ^ 2
REM Register the class:
PROC_class(MyClass{})
REM Instantiate the class:
... | Give a code snippet in #BBC_BASIC
In object-oriented programming class is a set (a transitive closure) of types bound by the relation of inheritance. It is said that all types derived from some base type T and the type T itself form a class T.
The first type T from the class T sometimes is called the root type of the... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Calculating_the_value_of_e | Calculating the value of e | Task
Calculate the value of e.
(e is also known as Euler's number and Napier's constant.)
See details: Calculating the value of e
| #Lambdatalk | Lambdatalk |
1) straightforward
{+ 1 {S.map {lambda {:n} {/ 1 {* {S.serie 1 :n}}}} {S.serie 1 17}}}
-> 2.7182818284590455
which is the value given by javascript : 2.718281828459045.
2) using recursion
{def fac
{lambda {:a :b}
{if {< :b 1}
then :a
else {fac {* :a :b} {- :b 1}}}}}
-> fac
{def euler
{lambda {:a :... | Give a code snippet in #Lambdatalk
Task
Calculate the value of e.
(e is also known as Euler's number and Napier's constant.)
See details: Calculating the value of e
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Substring | Substring |
Basic Data Operation
This is a basic data operation. It represents a fundamental action on a basic data type.
You may see other such operations in the Basic Data Operations category, or:
Integer Operations
Arithmetic |
Comparison
Boolean Operations
Bitwise |
Logical
String Operations
Concatenation |
Interpolation |... | #Rust | Rust |
let s = "abc文字化けdef";
let n = 2;
let m = 3;
// Print 3 characters starting at index 2 (c文字)
println!("{}", s.chars().skip(n).take(m).collect::<String>());
// Print all characters starting at index 2 (c文字化けdef)
println!("{}", s.chars().skip(n).collect::<String>());
// Print all characters except the ... | Give a code snippet in #Rust
Basic Data Operation
This is a basic data operation. It represents a fundamental action on a basic data type.
You may see other such operations in the Basic Data Operations category, or:
Integer Operations
Arithmetic |
Comparison
Boolean Operations
Bitwise |
Logical
String Operations
C... | 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... | #Ursa | Ursa | decl double k
while true
out "Temp. in Kelvin? " console
set k (in double console)
out "K\t" k endl "C\t" (- k 273.15) endl console
out "F\t" (- (* k 1.8) 459.67) endl "R\t" (* k 1.8) endl endl console
end while | Give a code snippet in #Ursa
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 k... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Keyboard_input/Obtain_a_Y_or_N_response | Keyboard input/Obtain a Y or N response |
Task
Obtain a valid Y or N response from the keyboard.
The keyboard should be flushed, so that any outstanding key-presses are removed, preventing any existing Y or N key-press from being evaluated.
The response should be obtained as soon as Y or N are pressed, and there should be no need t... | #PureBasic | PureBasic | PrintN("Press Y or N to continue")
Repeat
; Get the key being pressed, or a empty string.
Key$=UCase(Inkey())
;
; To Reduce the problems with an active loop
; a Delay(1) will release the CPU for the rest
; of this quanta if no key where pressed.
Delay(1)
Until Key$="Y" Or Key$="N"
PrintN("The response... | Give a code snippet in #PureBasic
Task
Obtain a valid Y or N response from the keyboard.
The keyboard should be flushed, so that any outstanding key-presses are removed, preventing any existing Y or N key-press from being evaluated.
The response should be obtained as soon as Y or N are pre... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Arbitrary-precision_integers_(included) | Arbitrary-precision integers (included) | Using the in-built capabilities of your language, calculate the integer value of:
5
4
3
2
... | #E | E | ? def value := 5**(4**(3**2)); null
? def decimal := value.toString(10); null
? decimal(0, 20)
# value: "62060698786608744707"
? decimal(decimal.size() - 20)
# value: "92256259918212890625"
? decimal.size()
# value: 183231 | Give a code snippet in #E
Using the in-built capabilities of your language, calculate the integer value of:
5
4
3
2
... | 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)
... | #Scala | Scala | object FizzBuzz extends App {
1 to 100 foreach { n =>
println((n % 3, n % 5) match {
case (0, 0) => "FizzBuzz"
case (0, _) => "Fizz"
case (_, 0) => "Buzz"
case _ => n
})
}
} | Give a code snippet in #Scala
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/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.
| #XPL0 | XPL0 | proc ShowSize(FileName);
char FileName; int Size, C;
[Trap(false); \disable abort on error
FSet(FOpen(FileName, 0), ^i);
Size:= 0;
repeat C:= ChIn(3); \reads 2 EOFs before
Size:= Size+1; \ read beyond end-of-file
until GetErr; \ is detected
IntOut(0, Size-2);
CrLf(0);
];
[ShowSize("in... | Give a code snippet in #XPL0
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/Gamma_function | Gamma function | Task
Implement one algorithm (or more) to compute the Gamma (
Γ
{\displaystyle \Gamma }
) function (in the real field only).
If your language has the function as built-in or you know a library which has it, compare your implementation's results with the results of the built-in/library function.
The Gamma funct... | #C.23 | C# | using System;
using System.Numerics;
static int g = 7;
static double[] p = {0.99999999999980993, 676.5203681218851, -1259.1392167224028,
771.32342877765313, -176.61502916214059, 12.507343278686905,
-0.13857109526572012, 9.9843695780195716e-6, 1.5056327351493116e-7};
Complex Gamma(Complex z)
{
// Ref... | Give a code snippet in #C.23
Task
Implement one algorithm (or more) to compute the Gamma (
Γ
{\displaystyle \Gamma }
) function (in the real field only).
If your language has the function as built-in or you know a library which has it, compare your implementation's results with the results of the built-in/libr... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Dragon_curve | Dragon curve |
Create and display a dragon curve fractal.
(You may either display the curve directly or write it to an image file.)
Algorithms
Here are some brief notes the algorithms used and how they might suit various languages.
Recursively a right curling dragon is a right dragon followed by a left dragon, at 90-degree an... | #Openscad | Openscad | level = 8;
linewidth = .1; // fraction of segment length
sqrt2 = pow(2, .5);
// Draw a dragon curve "level" going from [0,0] to [1,0]
module dragon(level) {
if (level <= 0) {
translate([.5,0]) cube([1+linewidth,linewidth,linewidth],center=true);
} else {
rotate(-45) scale(1/sqrt2) dragon(leve... | Give a code snippet in #Openscad
Create and display a dragon curve fractal.
(You may either display the curve directly or write it to an image file.)
Algorithms
Here are some brief notes the algorithms used and how they might suit various languages.
Recursively a right curling dragon is a right dragon followed... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Prime_decomposition | Prime decomposition | The prime decomposition of a number is defined as a list of prime numbers
which when all multiplied together, are equal to that number.
Example
12 = 2 × 2 × 3, so its prime decomposition is {2, 2, 3}
Task
Write a function which returns an array or collection which contains the prime decomposition of a given ... | #Racket | Racket |
#lang racket
(require math)
(define (factors n)
(append-map (λ (x) (make-list (cadr x) (car x))) (factorize n)))
| Give a code snippet in #Racket
The prime decomposition of a number is defined as a list of prime numbers
which when all multiplied together, are equal to that number.
Example
12 = 2 × 2 × 3, so its prime decomposition is {2, 2, 3}
Task
Write a function which returns an array or collection which contains the... | 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... | #Forth | Forth | : ints ( -- )
0 begin 1+ dup cr u. dup -1 = until drop ; | Give a code snippet in #Forth
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/Literals/Integer | Literals/Integer | Some programming languages have ways of expressing integer literals in bases other than the normal base ten.
Task
Show how integer literals can be expressed in as many bases as your language allows.
Note: this should not involve the calling of any functions/methods, but should be interpreted by the compiler or... | #hexiscript | hexiscript | # All equal to 15
println 15
println 000015 # Leading zeros are ignored
println 0b1111
println 0o17
println 0xf | Give a code snippet in #hexiscript
Some programming languages have ways of expressing integer literals in bases other than the normal base ten.
Task
Show how integer literals can be expressed in as many bases as your language allows.
Note: this should not involve the calling of any functions/methods, but shou... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Maze_solving | Maze solving | Task
For a maze generated by this task, write a function
that finds (and displays) the shortest path between two cells.
Note that because these mazes are generated by the Depth-first search algorithm, they contain no circular paths,
and a simple depth-first tree search can be used.
| #Julia | Julia | """
+ +---+---+
| 1 2 3 |
+---+ + +
| 4 5 | 6
+---+---+---+
julia> const graph = [
0 1 0 0 0 0;
1 0 1 0 1 0;
0 1 0 0 0 1;
0 0 0 0 1 0;
0 1 0 1 0 0;
0 0 1 0 0 0]
julia> dist, path = dijkstra(graph, 1)
... | Give a code snippet in #Julia
Task
For a maze generated by this task, write a function
that finds (and displays) the shortest path between two cells.
Note that because these mazes are generated by the Depth-first search algorithm, they contain no circular paths,
and a simple depth-first tree search can be used.
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/SHA-1 | SHA-1 | SHA-1 or SHA1 is a one-way hash function;
it computes a 160-bit message digest.
SHA-1 often appears in security protocols; for example,
many HTTPS websites use RSA with SHA-1 to secure their connections.
BitTorrent uses SHA-1 to verify downloads.
Git and Mercurial use SHA-1 digests to identify commits.
A US government... | #min | min | "Rosetta Code" sha1 puts! | Give a code snippet in #min
SHA-1 or SHA1 is a one-way hash function;
it computes a 160-bit message digest.
SHA-1 often appears in security protocols; for example,
many HTTPS websites use RSA with SHA-1 to secure their connections.
BitTorrent uses SHA-1 to verify downloads.
Git and Mercurial use SHA-1 digests to ident... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Phrase_reversals | Phrase reversals | Task
Given a string of space separated words containing the following phrase:
rosetta code phrase reversal
Reverse the characters of the string.
Reverse the characters of each individual word in the string, maintaining original word order within the string.
Reverse the order of each word of the string, maintaini... | #AutoHotkey | AutoHotkey | var =
(
Rosetta Code Phrase Reversal
)
array := strsplit(var, " ")
loop, % array.maxindex()
string .= array[array.maxindex() - A_index + 1] . " "
loop, % array.maxindex()
{
m := array[A_index]
array2 := strsplit(m, "")
Loop, % array2.maxindex()
string2 .= array2[array2.maxindex() - A_index + 1]
string2 .= ... | Give a code snippet in #AutoHotkey
Task
Given a string of space separated words containing the following phrase:
rosetta code phrase reversal
Reverse the characters of the string.
Reverse the characters of each individual word in the string, maintaining original word order within the string.
Reverse the order o... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Element-wise_operations | Element-wise operations | This task is similar to:
Matrix multiplication
Matrix transposition
Task
Implement basic element-wise matrix-matrix and scalar-matrix operations, which can be referred to in other, higher-order tasks.
Implement:
addition
subtraction
multiplication
division
exponentiation
Extend the task if ... | #Maple | Maple | # Built-in element-wise operator ~
#addition
<1,2,3;4,5,6> +~ 2;
#subtraction
<2,3,1,4;0,-2,-2,1> -~ 4;
#multiplication
<2,3,1,4;0,-2,-2,1> *~ 4;
#division
<2,3,7,9;6,8,4,5;7,0,10,11> /~ 2;
#exponentiation
<1,2,0; 7,2,7; 6,11,3>^~5; | Give a code snippet in #Maple
This task is similar to:
Matrix multiplication
Matrix transposition
Task
Implement basic element-wise matrix-matrix and scalar-matrix operations, which can be referred to in other, higher-order tasks.
Implement:
addition
subtraction
multiplication
division
expon... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Count_in_octal | Count in octal | Task
Produce a sequential count in octal, starting at zero, and using an increment of a one for each consecutive number.
Each number should appear on a single line, and the program should count until terminated, or until the maximum value of the numeric type in use is reached.
Related task
Integer sequ... | #Pascal | Pascal | program StrAdd;
{$Mode Delphi}
{$Optimization ON}
uses
sysutils;//IntToStr
const
maxCntOct = (SizeOf(NativeUint)*8+(3-1)) DIV 3;
procedure IntToOctString(i: NativeUint;var res:Ansistring);
var
p : array[0..maxCntOct] of byte;
c,cnt: LongInt;
begin
cnt := maxCntOct;
repeat
c := i AND 7;
p[cnt] :=... | Give a code snippet in #Pascal
Task
Produce a sequential count in octal, starting at zero, and using an increment of a one for each consecutive number.
Each number should appear on a single line, and the program should count until terminated, or until the maximum value of the numeric type in use is reached.
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Array_concatenation | Array concatenation | Task
Show how to concatenate two arrays in your language.
If this is as simple as array1 + array2, so be it.
| #i | i | main
a $= [1, 2, 3]
b $= [4, 5, 6]
print(a + b)
} | Give a code snippet in #i
Task
Show how to concatenate two arrays in your language.
If this is as simple as array1 + array2, so be it.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Fork | Fork | Task
Spawn a new process which can run simultaneously with, and independently of, the original parent process.
| #Icon_and_Unicon | Icon and Unicon | procedure main()
if (fork()|runerr(500)) = 0 then
write("child")
else {
delay(1000)
write("parent")
}
end | Give a code snippet in #Icon_and_Unicon
Task
Spawn a new process which can run simultaneously with, and independently of, the original parent process.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Sort_an_integer_array | Sort an integer array |
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
... | #Maple | Maple | sort([5,7,8,3,6,1]);
sort(Array([5,7,8,3,6,1])) | Give a code snippet in #Maple
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 | |
http://rosettacode.org/wiki/Biorhythms | Biorhythms | For a while in the late 70s, the pseudoscience of biorhythms was popular enough to rival astrology, with kiosks in malls that would give you your weekly printout. It was also a popular entry in "Things to Do with your Pocket Calculator" lists. You can read up on the history at Wikipedia, but the main takeaway is that u... | #Emacs_Lisp | Emacs Lisp | (require 'calendar)
(setq biorhythm-birthdate '(3 16 1953))
(defun biorhythm ()
"Show today's biorhythm."
(interactive)
(let* ((diff (abs (- (string-to-number (calendar-astro-date-string
biorhythm-birthdate)) (string-to-number
(calendar-astro-date-string)))))
(rhyt '(23 ... | Give a code snippet in #Emacs_Lisp
For a while in the late 70s, the pseudoscience of biorhythms was popular enough to rival astrology, with kiosks in malls that would give you your weekly printout. It was also a popular entry in "Things to Do with your Pocket Calculator" lists. You can read up on the history at Wikipe... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Matrix_transposition | Matrix transposition | Transpose an arbitrarily sized rectangular Matrix.
| #ActionScript | ActionScript | function transpose( m:Array):Array
{
//Assume each element in m is an array. (If this were production code, use typeof to be sure)
//Each element in m is a row, so this gets the length of a row in m,
//which is the same as the number of rows in m transpose.
var mTranspose = new Array(m[0].length);
for(var i:uin... | Give a code snippet in #ActionScript
Transpose an arbitrarily sized rectangular Matrix.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Read_a_specific_line_from_a_file | Read a specific line from a file | Some languages have special semantics for obtaining a known line number from a file.
Task
Demonstrate how to obtain the contents of a specific line within a file.
For the purpose of this task demonstrate how the contents of the seventh line of a file can be obtained, and store it in a variable or in memory (fo... | #D | D |
void main() {
import std.stdio, std.file, std.string;
auto file_lines = readText("input.txt").splitLines();
//file_lines becomes an array of strings, each line is one element
writeln((file_lines.length > 6) ? file_lines[6] : "line not found");
}
| Give a code snippet in #D
Some languages have special semantics for obtaining a known line number from a file.
Task
Demonstrate how to obtain the contents of a specific line within a file.
For the purpose of this task demonstrate how the contents of the seventh line of a file can be obtained, and store it in a ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sum_of_a_series | Sum of a series | Compute the nth term of a series, i.e. the sum of the n first terms of the corresponding sequence.
Informally this value, or its limit when n tends to infinity, is also called the sum of the series, thus the title of this task.
For this task, use:
S
n
=
∑
k
=
1
n
1
k
2
{\displa... | #E | E | pragma.enable("accumulator")
accum 0 for x in 1..1000 { _ + 1 / x ** 2 } | Give a code snippet in #E
Compute the nth term of a series, i.e. the sum of the n first terms of the corresponding sequence.
Informally this value, or its limit when n tends to infinity, is also called the sum of the series, thus the title of this task.
For this task, use:
S
n
=
∑
k
=
1
n... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Ternary_logic | Ternary logic |
This page uses content from Wikipedia. The original article was at Ternary logic. 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 logic, a three-valued logic (also trivalent, ternary, or trinary... | #Fortran | Fortran |
!-*- mode: compilation; default-directory: "/tmp/" -*-
!Compilation started at Mon May 20 23:05:46
!
!a=./f && make $a && $a < unixdict.txt
!gfortran -std=f2003 -Wall -ffree-form f.f03 -o f
!
!ternary not
! 1.0 0.5 0.0
!
!
!ternary and
! 0.0 0.0 0.0
! 0.0 0.5 0.5
! 0.0 0.5 1.0
!
!
!ternary or
! 0.0 0.5 1.0
! 0.5 0.5 ... | Give a code snippet in #Fortran
This page uses content from Wikipedia. The original article was at Ternary logic. 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 logic, a three-valued logic (al... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Accumulator_factory | Accumulator factory | A problem posed by Paul Graham is that of creating a function that takes a single (numeric) argument and which returns another function that is an accumulator. The returned accumulator function in turn also takes a single numeric argument, and returns the sum of all the numeric values passed in so far to that accumulat... | #Jsish | Jsish | /* Accumulator factory, in Jsish */
function accumulator(sum) {
return function(n) {
return sum += n;
};
}
provide('accumulatorFactory', '0.6');
if (Interp.conf('unitTest')) {
var x,y;
;x = accumulator(1);
;accumulator;
;x;
;x(5);
;accumulator(3);
;x(2.3);
;y = accumulator(0);
;y;
;x(1);
;y(2);
;x... | Give a code snippet in #Jsish
A problem posed by Paul Graham is that of creating a function that takes a single (numeric) argument and which returns another function that is an accumulator. The returned accumulator function in turn also takes a single numeric argument, and returns the sum of all the numeric values pas... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Bitwise_operations | Bitwise operations |
Basic Data Operation
This is a basic data operation. It represents a fundamental action on a basic data type.
You may see other such operations in the Basic Data Operations category, or:
Integer Operations
Arithmetic |
Comparison
Boolean Operations
Bitwise |
Logical
String Operations
Concatenation |
Interpolation |... | #Maple | Maple |
with(Bits):
bit:=proc(A,B)
local a,b,c,d,e,f,g,h,i,x,bitpow;
bitpow := 2^B:
a:=And(A,B);
b:=Not(A);
c:=Or(A,B);
d:=Xor(A,B);
#Left Shift
e:= irem(2*A,bitpow);
#Right Shift
f := iquo(A,2);
#Left Rotate
g:= irem(2*A,bitpow,'x')+x;
#Rightarithshift
i:= iquo(A,2)+bitpow/2*irem(A,bitpow/2);
return a,b,c,d,e,f,g,i;
end pro... | Give a code snippet in #Maple
Basic Data Operation
This is a basic data operation. It represents a fundamental action on a basic data type.
You may see other such operations in the Basic Data Operations category, or:
Integer Operations
Arithmetic |
Comparison
Boolean Operations
Bitwise |
Logical
String Operations
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Play_recorded_sounds | Play recorded sounds | Load at least two prerecorded sounds, and demonstrate as many of these features as you can:
playing them individually and simultaneously
stopping before the end of the sound
looping (preferably glitch-free)
setting the volume of each sound
stereo or 3D positional mixing
performing other actions when marked times... | #Wren | Wren | import "audio" for AudioEngine
import "dome" for Process
class Game {
static init() {
// load a .wav file and give it a friendly name
AudioEngine.load("a", "a.wav")
// play the file at volume v, looping l and pan p
__v = 2 // twice 'normal' volume
__l = true // loop ... | Give a code snippet in #Wren
Load at least two prerecorded sounds, and demonstrate as many of these features as you can:
playing them individually and simultaneously
stopping before the end of the sound
looping (preferably glitch-free)
setting the volume of each sound
stereo or 3D positional mixing
performing o... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Concurrent_computing | Concurrent computing | Task
Using either native language concurrency syntax or freely available libraries, write a program to display the strings "Enjoy" "Rosetta" "Code", one string per line, in random order.
Concurrency syntax must use threads, tasks, co-routines, or whatever concurrency is called in your language.
| #Wren | Wren | import "random" for Random
var words = ["Enjoy", "Rosetta", "Code"]
var rand = Random.new()
for (h in 1..3) {
var fibers = List.filled(3, null)
for (i in 0..2) fibers[i] = Fiber.new { System.print(words[i]) }
var called = List.filled(3, false)
var j = 0
while (j < 3) {
var k = rand.int(3)
... | Give a code snippet in #Wren
Task
Using either native language concurrency syntax or freely available libraries, write a program to display the strings "Enjoy" "Rosetta" "Code", one string per line, in random order.
Concurrency syntax must use threads, tasks, co-routines, or whatever concurrency is called in your la... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Get_system_command_output | Get system command output | Task
Execute a system command and get its output into the program. The output may be stored in any kind of collection (array, list, etc.).
Related task
Execute a system command
| #Java | Java | import java.io.*;
import java.util.*;
public class SystemCommand {
public static void main(String args[]) throws IOException {
String command = "cmd /c dir";
Process p = Runtime.getRuntime().exec(command);
try (Scanner sc = new Scanner(p.getInputStream())) {
System.out.... | Give a code snippet in #Java
Task
Execute a system command and get its output into the program. The output may be stored in any kind of collection (array, list, etc.).
Related task
Execute a system command
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Modular_inverse | Modular inverse | From Wikipedia:
In modular arithmetic, the modular multiplicative inverse of an integer a modulo m is an integer x such that
a
x
≡
1
(
mod
m
)
.
{\displaystyle a\,x\equiv 1{\pmod {m}}.}
Or in other words, such that:
∃
k
∈
Z
,
a
x
=
1
+
k
m
{\displaystyle \exists k\in \math... | #newLISP | newLISP |
(define (modular-multiplicative-inverse a n)
(if (< n 0)
(setf n (abs n)))
(if (< a 0)
(setf a (- n (% (- 0 a) n))))
(setf t 0)
(setf nt 1)
(setf r n)
(setf nr (mod a n))
(while (not (zero? nr))
(setf q (int (div r nr)))
(setf tmp nt)
(setf nt ... | Give a code snippet in #newLISP
From Wikipedia:
In modular arithmetic, the modular multiplicative inverse of an integer a modulo m is an integer x such that
a
x
≡
1
(
mod
m
)
.
{\displaystyle a\,x\equiv 1{\pmod {m}}.}
Or in other words, such that:
∃
k
∈
Z
,
a
x
=
1
+
k
m
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Comma_quibbling | Comma quibbling | Comma quibbling is a task originally set by Eric Lippert in his blog.
Task
Write a function to generate a string output which is the concatenation of input words from a list/sequence where:
An input of no words produces the output string of just the two brace characters "{}".
An input of just one word, e.g. ["AB... | #PicoLisp | PicoLisp | (for L '([] ["ABC"] ["ABC", "DEF"] ["ABC", "DEF", "G", "H"])
(let H (head -1 L)
(prinl
"{"
(glue ", " H)
(and H " and ")
(last L)
"}" ) ) ) | Give a code snippet in #PicoLisp
Comma quibbling is a task originally set by Eric Lippert in his blog.
Task
Write a function to generate a string output which is the concatenation of input words from a list/sequence where:
An input of no words produces the output string of just the two brace characters "{}".
An... | christopher/rosetta-code | |
http://rosettacode.org/wiki/World_Cup_group_stage | World Cup group stage | It's World Cup season (or at least it was when this page was created)!
The World Cup is an international football/soccer tournament that happens every 4 years. Countries put their international teams together in the years between tournaments and qualify for the tournament based on their performance in other internat... | #Scala | Scala | object GroupStage extends App { //team left digit vs team right digit
val games = Array("12", "13", "14", "23", "24", "34")
val points = Array.ofDim[Int](4, 10) //playing 3 games, points range from 0 to 9
var results = "000000" //start with left teams all losing
private def nextResult: Boolean = {
if (res... | Give a code snippet in #Scala
It's World Cup season (or at least it was when this page was created)!
The World Cup is an international football/soccer tournament that happens every 4 years. Countries put their international teams together in the years between tournaments and qualify for the tournament based on thei... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Checkpoint_synchronization | Checkpoint synchronization | The checkpoint synchronization is a problem of synchronizing multiple tasks. Consider a workshop where several workers (tasks) assembly details of some mechanism. When each of them completes his work they put the details together. There is no store, so a worker who finished its part first must wait for others before st... | #Wren | Wren | import "random" for Random
import "scheduler" for Scheduler
import "timer" for Timer
import "/ioutil" for Input
var rgen = Random.new()
var nWorkers = 0
var nTasks = 0
var nFinished = 0
var worker = Fn.new { |id|
var workTime = rgen.int(100, 1000) // 100..999 msec.
System.print("Worker %(id) will work for %... | Give a code snippet in #Wren
The checkpoint synchronization is a problem of synchronizing multiple tasks. Consider a workshop where several workers (tasks) assembly details of some mechanism. When each of them completes his work they put the details together. There is no store, so a worker who finished its part first ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sum_of_squares | Sum of squares | Task
Write a program to find the sum of squares of a numeric vector.
The program should work on a zero-length vector (with an answer of 0).
Related task
Mean
| #Asymptote | Asymptote | int suma;
int[] a={1, 2, 3, 4, 5, 6};
for(var i : a)
suma = suma + a[i] ^ 2;
write("The sum of squares is: ", suma); | Give a code snippet in #Asymptote
Task
Write a program to find the sum of squares of a numeric vector.
The program should work on a zero-length vector (with an answer of 0).
Related task
Mean
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Stack_traces | Stack traces | Many programming languages allow for introspection of the current call stack environment. This can be for a variety of purposes such as enforcing security checks, debugging, or for getting access to the stack frame of callers.
Task
Print out (in a manner considered suitable for the platform) the current call stack.... | #Java | Java | public class StackTracer {
public static void printStackTrace() {
StackTraceElement[] elems = Thread.currentThread().getStackTrace();
System.out.println("Stack trace:");
for (int i = elems.length-1, j = 2 ; i >= 3 ; i--, j+=2) {
System.out.printf("%" + j + "s%s.%s%n", "",
elems[i].getClassName(), el... | Give a code snippet in #Java
Many programming languages allow for introspection of the current call stack environment. This can be for a variety of purposes such as enforcing security checks, debugging, or for getting access to the stack frame of callers.
Task
Print out (in a manner considered suitable for the pla... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Lychrel_numbers | Lychrel numbers | Take an integer n, greater than zero.
Form the next n of its series by reversing the digits of the current n and adding the result to the current n.
Stop when n becomes palindromic - i.e. the digits of n in reverse order == n.
The above recurrence relation when applied to most starting numbers n = 1, 2, ... ... | #AppleScript | AppleScript | on Lychrels(numberLimit, iterationLimit)
script o
property digits : missing value -- Digits of the current startNumber or a derived sum.
property stigid : missing value -- Reverse thereof.
property digitLists : missing value -- Copies of the digit lists in the current sequence.
-- Th... | Give a code snippet in #AppleScript
Take an integer n, greater than zero.
Form the next n of its series by reversing the digits of the current n and adding the result to the current n.
Stop when n becomes palindromic - i.e. the digits of n in reverse order == n.
The above recurrence relation when applied to... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Doubly-linked_list/Element_definition | Doubly-linked list/Element definition | Task
Define the data structure for a doubly-linked list element.
The element should include a data member to hold its value and pointers to both the next element in the list and the previous element in the list.
The pointers should be mutable.
See also
Array
Associative array: Creation, Iteration
Collections
... | #Tcl | Tcl | oo::class create List {
variable content next prev
constructor {value {list ""}} {
set content $value
set next $list
set prev ""
if {$next ne ""} {
$next previous [self]
}
}
method value args {
set content {*}$args
}
method next args {
... | Give a code snippet in #Tcl
Task
Define the data structure for a doubly-linked list element.
The element should include a data member to hold its value and pointers to both the next element in the list and the previous element in the list.
The pointers should be mutable.
See also
Array
Associative array: Crea... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Terminal_control/Clear_the_screen | Terminal control/Clear the screen | Task
Clear the terminal window.
| #Ring | Ring | system('clear') | Give a code snippet in #Ring
Task
Clear the terminal window.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Find_duplicate_files | Find duplicate files | In a large directory structure it is easy to inadvertently leave unnecessary copies of files around, which can use considerable disk space and create confusion.
Task
Create a program which, given a minimum size and a folder/directory, will find all files of at least size bytes with duplicate contents under the dire... | #zkl | zkl | include(zkl.h.zkl);
const FLAGS=FILE.GLOB.IGNORE_CASE + FILE.GLOB.NO_DIRS;
var [const] MsgHash=Import("zklMsgHash");
var recurse=False, fileSpec, minSz=0, maxSz=(0).MAX;
argh:=Utils.Argh(
T("+R","R","Recurse into subdirectories, starting at <arg>",
fcn(arg){ recurse=arg }),
T("+minSz","","Only consider file... | Give a code snippet in #zkl
In a large directory structure it is easy to inadvertently leave unnecessary copies of files around, which can use considerable disk space and create confusion.
Task
Create a program which, given a minimum size and a folder/directory, will find all files of at least size bytes with dupl... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Find_the_last_Sunday_of_each_month | Find the last Sunday of each month | Write a program or a script that returns the last Sundays of each month of a given year. The year may be given through any simple input method in your language (command line, std in, etc).
Example of an expected output:
./last_sundays 2013
2013-01-27
2013-02-24
2013-03-31
2013-04-28
2013-05-26
2013-06-30
2013-07-28
2... | #OCaml | OCaml |
let is_leap_year y =
(* See OCaml solution on Rosetta Code for
determing if it's a leap year *)
if (y mod 100) = 0
then (y mod 400) = 0
else (y mod 4) = 0;;
let get_days y =
if is_leap_year y
then
[31;29;31;30;31;30;31;31;30;31;30;31]
else
[31;28;31;30;31;30;31;31;30;31;30;3... | Give a code snippet in #OCaml
Write a program or a script that returns the last Sundays of each month of a given year. The year may be given through any simple input method in your language (command line, std in, etc).
Example of an expected output:
./last_sundays 2013
2013-01-27
2013-02-24
2013-03-31
2013-04-28
201... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Number_reversal_game | Number reversal game | Task
Given a jumbled list of the numbers 1 to 9 that are definitely not in
ascending order.
Show the list, and then ask the player how many digits from the
left to reverse.
Reverse those digits, then ask again, until all the digits end up in ascending order.
The score is the count of the reversa... | #Python | Python | '''
number reversal game
Given a jumbled list of the numbers 1 to 9
Show the list.
Ask the player how many digits from the left to reverse.
Reverse those digits then ask again.
until all the digits end up in ascending order.
'''
import random
print(__doc__)
data, trials = list('123456789'), 0
... | Give a code snippet in #Python
Task
Given a jumbled list of the numbers 1 to 9 that are definitely not in
ascending order.
Show the list, and then ask the player how many digits from the
left to reverse.
Reverse those digits, then ask again, until all the digits end up in ascending order.
The s... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Greatest_subsequential_sum | Greatest subsequential sum | Task
Given a sequence of integers, find a continuous subsequence which maximizes the sum of its elements, that is, the elements of no other single subsequence add up to a value larger than this one.
An empty subsequence is considered to have the sum of 0; thus if all elements are negative, the result must be th... | #Ring | Ring |
# Project : Greatest subsequential sum
aList1 = [0, 1, 2, -3, 3, -1, 0, -4, 0, -1, -4, 2]
see "[0, 1, 2, -3, 3, -1, 0, -4, 0, -1, -4, 2] -> " + sum(aList1) + nl
aList2 = [-1, -2, 3, 5, 6, -2, -1, 4, -4, 2, -1]
see "[-1, -2, 3, 5, 6, -2, -1, 4, -4, 2, -1] -> " + sum(aList2) + nl
aList3 = [-1, -2, -3, -4, -5]
see "... | Give a code snippet in #Ring
Task
Given a sequence of integers, find a continuous subsequence which maximizes the sum of its elements, that is, the elements of no other single subsequence add up to a value larger than this one.
An empty subsequence is considered to have the sum of 0; thus if all elements are n... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Variable-length_quantity | Variable-length quantity | Implement some operations on variable-length quantities, at least including conversions from a normal number in the language to the binary representation of the variable-length quantity for that number, and vice versa. Any variants are acceptable.
Task
With above operations,
convert these two numbers 0x200000 (209... | #Bracmat | Bracmat | ( ( VLQ
= b07 b8 vlq
. 0:?b8
& :?vlq
& whl
' ( !arg:>0
& mod$(!arg.128):?b07
& (chr$(!b8+!b07)|) !vlq:?vlq
& 128:?b8
& div$(!arg.128):?arg
)
& str$!vlq
)
& ( NUM
= c num d
. 0:?num:?d
& whl
' ( @(!arg:%@... | Give a code snippet in #Bracmat
Implement some operations on variable-length quantities, at least including conversions from a normal number in the language to the binary representation of the variable-length quantity for that number, and vice versa. Any variants are acceptable.
Task
With above operations,
conver... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Harshad_or_Niven_series | Harshad or Niven series | The Harshad or Niven numbers are positive integers ≥ 1 that are divisible by the sum of their digits.
For example, 42 is a Harshad number as 42 is divisible by (4 + 2) without remainder.
Assume that the series is defined as the numbers in increasing order.
Task
The task is to create a function/method/... | #F.C5.8Drmul.C3.A6 | Fōrmulæ | Public Sub Main()
Dim siCount, siLoop, siTotal, siCounter As Short
Dim sNo, sTemp As String
Dim sHold, sNiven As New String[]
For siCount = 1 To 1500
sNo = Str(siCount)
For siLoop = 1 To Len(sNo)
sHold.Add(Mid(sNo, siLoop, 1))
Next
For Each sTemp In sHold
siTotal += Val(sTemp)
Next
If siCount Mod ... | Give a code snippet in #F.C5.8Drmul.C3.A6
The Harshad or Niven numbers are positive integers ≥ 1 that are divisible by the sum of their digits.
For example, 42 is a Harshad number as 42 is divisible by (4 + 2) without remainder.
Assume that the series is defined as the numbers in increasing order.
Tas... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Mutual_recursion | Mutual recursion | Two functions are said to be mutually recursive if the first calls the second,
and in turn the second calls the first.
Write two mutually recursive functions that compute members of the Hofstadter Female and Male sequences defined as:
F
(
0
)
=
1
;
M
(
0
)
=
0
F
(
n
)
=
n
−
M
(
F
(
n
−
1
)
)
,
... | #PL.2FI | PL/I | test: procedure options (main);
M: procedure (n) returns (fixed) recursive; /* 8/1/2010 */
declare n fixed;
if n <= 0 then return (0);
else return ( n - F(M(n-1)) );
end M;
F: procedure (n) returns (fixed) recursive;
declare n fixed;
if n <= 0 then return (1);
else return ( n - M(F(n-1)) );
en... | Give a code snippet in #PL.2FI
Two functions are said to be mutually recursive if the first calls the second,
and in turn the second calls the first.
Write two mutually recursive functions that compute members of the Hofstadter Female and Male sequences defined as:
F
(
0
)
=
1
;
M
(
0
)
=
0
F
(
n... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Text_processing/1 | Text processing/1 | This task has been flagged for clarification. Code on this page in its current state may be flagged incorrect once this task has been clarified. See this page's Talk page for discussion.
Often data is produced by one program, in the wrong format for later use by another program or person. In these situations another pr... | #Java | Java | import java.io.File;
import java.util.*;
import static java.lang.System.out;
public class TextProcessing1 {
public static void main(String[] args) throws Exception {
Locale.setDefault(new Locale("en", "US"));
Metrics metrics = new Metrics();
int dataGap = 0;
String gapBeginDate... | Give a code snippet in #Java
This task has been flagged for clarification. Code on this page in its current state may be flagged incorrect once this task has been clarified. See this page's Talk page for discussion.
Often data is produced by one program, in the wrong format for later use by another program or person. ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sort_a_list_of_object_identifiers | Sort a list of object identifiers |
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
... | #M2000_Interpreter | M2000 Interpreter |
Module CheckIt {
Flush ' empty stack of values
Data "1.3.6.1.4.1.11.2.17.19.3.4.0.4" , "1.3.6.1.4.1.11.2.17.19.3.4.0.1", "1.3.6.1.4.1.11150.3.4.0.1"
Data "1.3.6.1.4.1.11.2.17.19.3.4.0.10", "1.3.6.1.4.1.11.2.17.5.2.0.79", "1.3.6.1.4.1.11150.3.4.0"
\\ Inventories of type queue can get same ke... | Give a code snippet in #M2000_Interpreter
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 sor... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Active_Directory/Connect | Active Directory/Connect | The task is to establish a connection to an Active Directory or Lightweight Directory Access Protocol server.
| #Raku | Raku | use LMDB;
my %DB := LMDB::DB.open(:path<some-dir>, %connection-parameters);
| Give a code snippet in #Raku
The task is to establish a connection to an Active Directory or Lightweight Directory Access Protocol server.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Morse_code | Morse code | Morse code
It has been in use for more than 175 years — longer than any other electronic encoding system.
Task
Send a string as audible Morse code to an audio device (e.g., the PC speaker).
As the standard Morse code does not contain all possible characters,
you may either ignore unknown characters in the file... | #Go | Go | // Command morse translates an input string into morse code,
// showing the output on the console, and playing it as sound.
// Only works on ubuntu.
package main
import (
"flag"
"fmt"
"log"
"regexp"
"strings"
"syscall"
"time"
"unicode"
)
// A key represents an action on the morse key.
// It's either on or o... | Give a code snippet in #Go
Morse code
It has been in use for more than 175 years — longer than any other electronic encoding system.
Task
Send a string as audible Morse code to an audio device (e.g., the PC speaker).
As the standard Morse code does not contain all possible characters,
you may either ignore un... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Arithmetic/Complex | Arithmetic/Complex | A complex number is a number which can be written as:
a
+
b
×
i
{\displaystyle a+b\times i}
(sometimes shown as:
b
+
a
×
i
{\displaystyle b+a\times i}
where
a
{\displaystyle a}
and
b
{\displaystyle b}
are real numbers, and
i
{\displaystyle i}
is √ -1
Typica... | #Ada | Ada | with Ada.Numerics.Generic_Complex_Types;
with Ada.Text_IO.Complex_IO;
procedure Complex_Operations is
-- Ada provides a pre-defined generic package for complex types
-- That package contains definitions for composition,
-- negation, addition, subtraction, multiplication, division,
-- conjugation, exponent... | Give a code snippet in #Ada
A complex number is a number which can be written as:
a
+
b
×
i
{\displaystyle a+b\times i}
(sometimes shown as:
b
+
a
×
i
{\displaystyle b+a\times i}
where
a
{\displaystyle a}
and
b
{\displaystyle b}
are real numbers, and
i
{\displaystyl... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Take_notes_on_the_command_line | Take notes on the command line | Take notes on the command line is part of Short Circuit's Console Program Basics selection.
Invoking NOTES without commandline arguments displays the current contents of the local NOTES.TXT if it exists.
If NOTES has arguments, the current date and time are appended to the local NOTES.TXT followed by a newline.
Then al... | #REXX | REXX | /*REXX program implements the "NOTES" command (append text to a file from the C.L.).*/
timestamp=right(date(),11,0) time() date('W') /*create a (current) date & time stamp.*/
nFID = 'NOTES.TXT' /*the fileID of the "notes" file. */
if 'f2'x==2 then tab="05"x ... | Give a code snippet in #REXX
Take notes on the command line is part of Short Circuit's Console Program Basics selection.
Invoking NOTES without commandline arguments displays the current contents of the local NOTES.TXT if it exists.
If NOTES has arguments, the current date and time are appended to the local NOTES.TXT ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Address_of_a_variable | Address of a variable |
Basic Data Operation
This is a basic data operation. It represents a fundamental action on a basic data type.
You may see other such operations in the Basic Data Operations category, or:
Integer Operations
Arithmetic |
Comparison
Boolean Operations
Bitwise |
Logical
String Operations
Concatenation |
Interpolation |... | #XLISP | XLISP | (%ADDRESS-OF X) | Give a code snippet in #XLISP
Basic Data Operation
This is a basic data operation. It represents a fundamental action on a basic data type.
You may see other such operations in the Basic Data Operations category, or:
Integer Operations
Arithmetic |
Comparison
Boolean Operations
Bitwise |
Logical
String Operations
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/One-dimensional_cellular_automata | One-dimensional cellular automata | Assume an array of cells with an initial distribution of live and dead cells,
and imaginary cells off the end of the array having fixed values.
Cells in the next generation of the array are calculated based on the value of the cell and its left and right nearest neighbours in the current generation.
If, in the follow... | #Red | Red | Red [
Purpose: "One-dimensional cellular automata"
Author: "Joe Smith"
]
vals: [0 1 0]
kill: [[0 0] [#[none] 0] [0 #[none]]]
evo: function [petri] [
new-petri: copy petri
while [petri/1] [
if all [petri/-1 = 1 petri/2 = 1] [new-petri/1: select vals petri/1]
if find/only kill reduce [petri/-1 petri/2] [n... | Give a code snippet in #Red
Assume an array of cells with an initial distribution of live and dead cells,
and imaginary cells off the end of the array having fixed values.
Cells in the next generation of the array are calculated based on the value of the cell and its left and right nearest neighbours in the current g... | 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... | #Phix | Phix | with javascript_semantics
function horner(atom x, sequence coeff)
atom res = 0
for i=length(coeff) to 1 by -1 do
res = res*x + coeff[i]
end for
return res
end function
?horner(3,{-19, 7, -4, 6})
| Give a code snippet in #Phix
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
)
{\d... | christopher/rosetta-code |
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