task_url stringlengths 30 116 | task_name stringlengths 2 86 | task_description stringlengths 0 14.4k | language_url stringlengths 2 53 | language_name stringlengths 1 52 | code stringlengths 0 61.9k |
|---|---|---|---|---|---|
http://rosettacode.org/wiki/Faulhaber%27s_formula | Faulhaber's formula | In mathematics, Faulhaber's formula, named after Johann Faulhaber, expresses the sum of the p-th powers of the first n positive integers as a (p + 1)th-degree polynomial function of n, the coefficients involving Bernoulli numbers.
Task
Generate the first 10 closed-form expressions, starting with p = 0.
R... | #Kotlin | Kotlin | // version 1.1.2
fun gcd(a: Long, b: Long): Long = if (b == 0L) a else gcd(b, a % b)
class Frac : Comparable<Frac> {
val num: Long
val denom: Long
companion object {
val ZERO = Frac(0, 1)
val ONE = Frac(1, 1)
}
constructor(n: Long, d: Long) {
require(d != 0L)
... |
http://rosettacode.org/wiki/Fibonacci_n-step_number_sequences | Fibonacci n-step number sequences | These number series are an expansion of the ordinary Fibonacci sequence where:
For
n
=
2
{\displaystyle n=2}
we have the Fibonacci sequence; with initial values
[
1
,
1
]
{\displaystyle [1,1]}
and
F
k
2
=
F
k
−
1
2
+
F
k
−
2
2
{\displaystyle F_{k}^{2}=F_{k-1}^{2}+F_{k-2}^{2}}
... | #Clojure | Clojure | (defn nacci [init]
(letfn [(s [] (lazy-cat init (apply map + (map #(drop % (s)) (range (count init))))))]
(s)))
(let [show (fn [name init] (println "first 20" name (take 20 (nacci init))))]
(show "Fibonacci" [1 1])
(show "Tribonacci" [1 1 2])
(show "Tetranacci" [1 1 2 4])
(show "Lucas" [2 1])) |
http://rosettacode.org/wiki/File_modification_time | File modification time | Task
Get and set the modification time of a file.
| #Wren | Wren | /* file_mod_time_wren */
import "./date" for Date
foreign class Stat {
construct new(fileName) {}
foreign atime
foreign mtime
}
foreign class Utimbuf {
construct new(actime, modtime) {}
foreign utime(fileName)
}
// gets a Date object from a Unix time in seconds
var UT2Date = Fn.new { |ut... |
http://rosettacode.org/wiki/File_modification_time | File modification time | Task
Get and set the modification time of a file.
| #zkl | zkl | info:=File.info("input.txt");
// -->T(size,last status change time,last mod time,isDir,mode), from stat(2)
info.println();
Time.Date.ctime(info[2]).println();
File.setModTime("input.txt",Time.Clock.mktime(2014,2,1,0,0,0));
File.info("input.txt")[2] : Time.Date.ctime(_).println(); |
http://rosettacode.org/wiki/Find_common_directory_path | Find common directory path | Create a routine that, given a set of strings representing directory paths and a single character directory separator, will return a string representing that part of the directory tree that is common to all the directories.
Test your routine using the forward slash '/' character as the directory separator and the foll... | #PowerShell | PowerShell |
<#
.Synopsis
Finds the deepest common directory path of files passed through the pipeline.
.Parameter File
PowerShell file object.
#>
function Get-CommonPath {
[CmdletBinding()]
param (
[Parameter(Mandatory=$true, ValueFromPipeline=$true)]
[System.IO.FileInfo] $File
)
process {
... |
http://rosettacode.org/wiki/Find_common_directory_path | Find common directory path | Create a routine that, given a set of strings representing directory paths and a single character directory separator, will return a string representing that part of the directory tree that is common to all the directories.
Test your routine using the forward slash '/' character as the directory separator and the foll... | #Prolog | Prolog |
%! directory_prefix(PATHs,STOP0,PREFIX)
directory_prefix([],_STOP0_,'')
:-
!
.
directory_prefix(PATHs0,STOP0,PREFIX)
:-
prolog:once(longest_prefix(PATHs0,STOP0,LONGEST_PREFIX)) ->
prolog:atom_concat(PREFIX,STOP0,LONGEST_PREFIX) ;
PREFIX=''
.
%! longest_prefix(PATHs,STOP0,PREFIX)
longest_prefix(PATHs0,STOP0... |
http://rosettacode.org/wiki/Filter | Filter | Task
Select certain elements from an Array into a new Array in a generic way.
To demonstrate, select all even numbers from an Array.
As an option, give a second solution which filters destructively,
by modifying the original Array rather than creating a new Array.
| #EchoLisp | EchoLisp |
(iota 12) → { 0 1 2 3 4 5 6 7 8 9 10 11 }
;; lists
(filter even? (iota 12))
→ (0 2 4 6 8 10)
;; array (non destructive)
(vector-filter even? #(1 2 3 4 5 6 7 8 9 10 11 12 13))
→ #( 2 4 6 8 10 12)
;; sequence, infinite, lazy
(lib 'sequences)
(define evens (filter even? [0 ..]))
(take evens 12)
→ (0 ... |
http://rosettacode.org/wiki/Find_limit_of_recursion | Find limit of recursion | Find limit of recursion is part of Short Circuit's Console Program Basics selection.
Task
Find the limit of recursion.
| #Sidef | Sidef | func recurse(n) {
say n;
recurse(n+1);
}
recurse(0); |
http://rosettacode.org/wiki/Find_limit_of_recursion | Find limit of recursion | Find limit of recursion is part of Short Circuit's Console Program Basics selection.
Task
Find the limit of recursion.
| #Smalltalk | Smalltalk |
Object subclass: #RecursionTest
instanceVariableNames: ''
classVariableNames: ''
poolDictionaries: ''
category: 'RosettaCode'
|
http://rosettacode.org/wiki/Find_limit_of_recursion | Find limit of recursion | Find limit of recursion is part of Short Circuit's Console Program Basics selection.
Task
Find the limit of recursion.
| #Standard_ML | Standard ML | fun recLimit () =
1 + recLimit ()
handle _ => 0
val () = print (Int.toString (recLimit ()) ^ "\n") |
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)
... | #HicEst | HicEst | DO i = 1, 100
IF( MOD(i, 15) == 0 ) THEN
WRITE() "FizzBuzz"
ELSEIF( MOD(i, 5) == 0 ) THEN
WRITE() "Buzz"
ELSEIF( MOD(i, 3) == 0 ) THEN
WRITE() "Fizz"
ELSE
WRITE() i
ENDIF
ENDDO |
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.
| #PowerShell | PowerShell | Get-ChildItem input.txt | Select-Object Name,Length
Get-ChildItem \input.txt | Select-Object Name,Length |
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.
| #PureBasic | PureBasic | Debug FileSize("input.txt")
Debug FileSize("/input.txt") |
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.
| #Python | Python | import os
size = os.path.getsize('input.txt')
size = os.path.getsize('/input.txt') |
http://rosettacode.org/wiki/File_input/output | File input/output | File input/output is part of Short Circuit's Console Program Basics selection.
Task
Create a file called "output.txt", and place in it the contents of the file "input.txt", via an intermediate variable.
In other words, your program will demonstrate:
how to read from a file into a variable
how to write ... | #i | i | software {
file = load("input.txt")
open("output.txt").write(file)
} |
http://rosettacode.org/wiki/File_input/output | File input/output | File input/output is part of Short Circuit's Console Program Basics selection.
Task
Create a file called "output.txt", and place in it the contents of the file "input.txt", via an intermediate variable.
In other words, your program will demonstrate:
how to read from a file into a variable
how to write ... | #Icon_and_Unicon | Icon and Unicon | procedure main()
in := open(f := "input.txt","r") | stop("Unable to open ",f)
out := open(f := "output.txt","w") | stop("Unable to open ",f)
while write(out,read(in))
end |
http://rosettacode.org/wiki/Fibonacci_word | Fibonacci word | The Fibonacci Word may be created in a manner analogous to the Fibonacci Sequence as described here:
Define F_Word1 as 1
Define F_Word2 as 0
Form F_Word3 as F_Word2 concatenated with F_Word1 i.e.: 01
Form F_Wordn as F_Wordn-1 concatenated with F_wordn-... | #Mathematica_.2F_Wolfram_Language | Mathematica / Wolfram Language | entropy = (p - 1) Log[2, 1 - p] - p Log[2, p];
TableForm[
Table[{k, Fibonacci[k],
Quiet@Check[N[entropy /. {p -> Fibonacci[k - 1]/Fibonacci[k]}, 15],
0]}, {k, 37}],
TableHeadings -> {None, {"N", "Length", "Entropy"}}] |
http://rosettacode.org/wiki/Fibonacci_word | Fibonacci word | The Fibonacci Word may be created in a manner analogous to the Fibonacci Sequence as described here:
Define F_Word1 as 1
Define F_Word2 as 0
Form F_Word3 as F_Word2 concatenated with F_Word1 i.e.: 01
Form F_Wordn as F_Wordn-1 concatenated with F_wordn-... | #Nim | Nim | import math, strformat, strutils
func entropy(str: string): float =
## return the entropy of a fibword string.
if str.len <= 1: return 0.0
let strlen = str.len.toFloat
let count0 = str.count('0').toFloat
let count1 = strlen - count0
result = -(count0 / strlen * log2(count0 / strlen) + count1 / strlen * ... |
http://rosettacode.org/wiki/FASTA_format | FASTA format | In bioinformatics, long character strings are often encoded in a format called FASTA.
A FASTA file can contain several strings, each identified by a name marked by a > (greater than) character at the beginning of the line.
Task
Write a program that reads a FASTA file such as:
>Rosetta_Example_1
THERECANBENOSPACE
... | #PicoLisp | PicoLisp | (de fasta (F)
(in F
(while (from ">")
(prin (line T) ": ")
(until (or (= ">" (peek)) (eof))
(prin (line T)) )
(prinl) ) ) )
(fasta "fasta.dat") |
http://rosettacode.org/wiki/FASTA_format | FASTA format | In bioinformatics, long character strings are often encoded in a format called FASTA.
A FASTA file can contain several strings, each identified by a name marked by a > (greater than) character at the beginning of the line.
Task
Write a program that reads a FASTA file such as:
>Rosetta_Example_1
THERECANBENOSPACE
... | #PowerShell | PowerShell |
$file = @'
>Rosetta_Example_1
THERECANBENOSPACE
>Rosetta_Example_2
THERECANBESEVERAL
LINESBUTTHEYALLMUST
BECONCATENATED
'@
$lines = $file.Replace("`n","~").Split(">").ForEach({$_.TrimEnd("~").Split("`n",2,[StringSplitOptions]::RemoveEmptyEntries)})
$output = New-Object -TypeName PSObject
foreach ($line in $line... |
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 ... | #68000_Assembly | 68000 Assembly | fib:
MOVEM.L D4-D5,-(SP)
MOVE.L D0,D4
MOVEQ #0,D5
CMP.L #2,D0
BCS .bar
MOVEQ #0,D5
.foo:
MOVE.L D4,D0
SUBQ.L #1,D0
JSR fib
SUBQ.L #2,D4
ADD.L D0,D5
CMP.L #1,D4
BHI .foo
.bar:
MOVE.L D5,D0
ADD.L D4,D0
MOVEM.L (SP)+,D4-D5
RTS |
http://rosettacode.org/wiki/Factors_of_an_integer | Factors of an integer |
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 |... | #Action.21 | Action! | PROC PrintFactors(CARD a)
BYTE notFirst
CARD p
p=1 notFirst=0
WHILE p<=a
DO
IF a MOD p=0 THEN
IF notFirst THEN
Print(", ")
FI
notFirst=1
PrintC(p)
FI
p==+1
OD
RETURN
PROC Test(CARD a)
PrintF("Factors of %U: ",a)
PrintFactors(a)
PutE()
RETURN
PROC Main(... |
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)... | #Crystal | Crystal | require "complex"
def fft(x : Array(Int32 | Float64)) #: Array(Complex)
return [x[0].to_c] if x.size <= 1
even = fft(Array.new(x.size // 2) { |k| x[2 * k] })
odd = fft(Array.new(x.size // 2) { |k| x[2 * k + 1] })
c = Array.new(x.size // 2) { |k| Math.exp((-2 * Math::PI * k / x.size).i) }
codd = Array.new(x... |
http://rosettacode.org/wiki/Factors_of_a_Mersenne_number | Factors of a Mersenne number | A Mersenne number is a number in the form of 2P-1.
If P is prime, the Mersenne number may be a Mersenne prime
(if P is not prime, the Mersenne number is also not prime).
In the search for Mersenne prime numbers it is advantageous to eliminate exponents by finding a small factor before starting a, potentially lengthy,... | #C.2B.2B | C++ | #include <iostream>
#include <cstdint>
typedef uint64_t integer;
integer bit_count(integer n) {
integer count = 0;
for (; n > 0; count++)
n >>= 1;
return count;
}
integer mod_pow(integer p, integer n) {
integer square = 1;
for (integer bits = bit_count(p); bits > 0; square %= n) {
... |
http://rosettacode.org/wiki/Farey_sequence | Farey sequence | The Farey sequence Fn of order n is the sequence of completely reduced fractions between 0 and 1 which, when in lowest terms, have denominators less than or equal to n, arranged in order of increasing size.
The Farey sequence is sometimes incorrectly called a Farey series.
Each Farey se... | #EDSAC_order_code | EDSAC order code |
[Farey sequence for Rosetta Code website.
EDSAC program, Initial Orders 2.
Prints Farey sequences up to order 11
(or other limit determined by a simple edit).]
[Modification of library subroutine P6.
Prints number (absolute value <= 65535)
passed in 0F, without leading spaces.
41 locations.]
... |
http://rosettacode.org/wiki/Farey_sequence | Farey sequence | The Farey sequence Fn of order n is the sequence of completely reduced fractions between 0 and 1 which, when in lowest terms, have denominators less than or equal to n, arranged in order of increasing size.
The Farey sequence is sometimes incorrectly called a Farey series.
Each Farey se... | #Factor | Factor | USING: formatting io kernel math math.primes.factors math.ranges
locals prettyprint sequences sequences.extras sets tools.time ;
IN: rosetta-code.farey-sequence
! Given the order n and a farey pair, calculate the next member
! of the sequence.
:: p/q ( n a/b c/d -- p/q )
a/b c/d [ >fraction ] bi@ :> ( a b c d )
... |
http://rosettacode.org/wiki/Fairshare_between_two_and_more | Fairshare between two and more | The Thue-Morse sequence is a sequence of ones and zeros that if two people
take turns in the given order, the first persons turn for every '0' in the
sequence, the second for every '1'; then this is shown to give a fairer, more
equitable sharing of resources. (Football penalty shoot-outs for example, might
not favour t... | #Lua | Lua | function turn(base, n)
local sum = 0
while n ~= 0 do
local re = n % base
n = math.floor(n / base)
sum = sum + re
end
return sum % base
end
function fairShare(base, count)
io.write(string.format("Base %2d:", base))
for i=1,count do
local t = turn(base, i - 1)
... |
http://rosettacode.org/wiki/Faulhaber%27s_triangle | Faulhaber's triangle | Named after Johann Faulhaber, the rows of Faulhaber's triangle are the coefficients of polynomials that represent sums of integer powers, which are extracted from Faulhaber's formula:
∑
k
=
1
n
k
p
=
1
p
+
1
∑
j
=
0
p
(
p
+
1
j
)
B
j
n
p
+
1
−
j
{\displaystyle \sum _{k... | #jq | jq | include "Rational";
# Preliminaries
def lpad($len): tostring | ($len - length) as $l | (" " * $l)[:$l] + .;
# for gojq
def idivide($j):
. as $i
| ($i % $j) as $mod
| ($i - $mod) / $j ;
# use idivide for precision
def binomial(n; k):
if k > n / 2 then binomial(n; n-k)
else reduce range(1; k+1) as $i (1; ... |
http://rosettacode.org/wiki/Faulhaber%27s_formula | Faulhaber's formula | In mathematics, Faulhaber's formula, named after Johann Faulhaber, expresses the sum of the p-th powers of the first n positive integers as a (p + 1)th-degree polynomial function of n, the coefficients involving Bernoulli numbers.
Task
Generate the first 10 closed-form expressions, starting with p = 0.
R... | #Lua | Lua | function binomial(n,k)
if n<0 or k<0 or n<k then return -1 end
if n==0 or k==0 then return 1 end
local num = 1
for i=k+1,n do
num = num * i
end
local denom = 1
for i=2,n-k do
denom = denom * i
end
return num / denom
end
function gcd(a,b)
while b ~= 0 do
... |
http://rosettacode.org/wiki/Fibonacci_n-step_number_sequences | Fibonacci n-step number sequences | These number series are an expansion of the ordinary Fibonacci sequence where:
For
n
=
2
{\displaystyle n=2}
we have the Fibonacci sequence; with initial values
[
1
,
1
]
{\displaystyle [1,1]}
and
F
k
2
=
F
k
−
1
2
+
F
k
−
2
2
{\displaystyle F_{k}^{2}=F_{k-1}^{2}+F_{k-2}^{2}}
... | #CLU | CLU | % Find the Nth element of a given n-step sequence
n_step = proc (seq: sequence[int], n: int) returns (int)
a: array[int] := sequence[int]$s2a(seq)
for i: int in int$from_to(1,n) do
sum: int := 0
for x: int in array[int]$elements(a) do
sum := sum + x
end
array[int]$r... |
http://rosettacode.org/wiki/Find_common_directory_path | Find common directory path | Create a routine that, given a set of strings representing directory paths and a single character directory separator, will return a string representing that part of the directory tree that is common to all the directories.
Test your routine using the forward slash '/' character as the directory separator and the foll... | #PureBasic | PureBasic | Procedure.s CommonPath(Array InPaths.s(1),separator.s="/")
Protected SOut$=""
Protected i, j, toggle
If ArraySize(InPaths())=0
ProcedureReturn InPaths(0) ; Special case, only one path
EndIf
Repeat
i+1
toggle=#False
For j=1 To ArraySize(InPaths())
If (StringField(InPaths(j-1),i,separ... |
http://rosettacode.org/wiki/Filter | Filter | Task
Select certain elements from an Array into a new Array in a generic way.
To demonstrate, select all even numbers from an Array.
As an option, give a second solution which filters destructively,
by modifying the original Array rather than creating a new Array.
| #Ela | Ela | open list
evenList = filter' (\x -> x % 2 == 0) [1..] |
http://rosettacode.org/wiki/Find_limit_of_recursion | Find limit of recursion | Find limit of recursion is part of Short Circuit's Console Program Basics selection.
Task
Find the limit of recursion.
| #Swift | Swift | var n = 1
func recurse() {
print(n)
n += 1
recurse()
}
recurse() |
http://rosettacode.org/wiki/Find_limit_of_recursion | Find limit of recursion | Find limit of recursion is part of Short Circuit's Console Program Basics selection.
Task
Find the limit of recursion.
| #Tcl | Tcl | proc recur i {
puts "This is depth [incr i]"
catch {recur $i}; # Trap error from going too deep
}
recur 0 |
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)
... | #HolyC | HolyC | U8 i;
for (i = 1; i <= 100; i++) {
if (!(i % 15))
Print("FizzBuzz");
else if (!(i % 3))
Print("Fizz");
else if (!(i % 5))
Print("Buzz");
else
Print("%d", i);
Print("\n");
} |
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.
| #R | R | sizeinwd <- file.info('input.txt')[["size"]]
sizeinroot <- file.info('/input.txt')[["size"]] |
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.
| #Racket | Racket | #lang racket
(file-size "input.txt")
(file-size "/input.txt") |
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.
| #Raku | Raku | say 'input.txt'.IO.s;
say '/input.txt'.IO.s; |
http://rosettacode.org/wiki/File_input/output | File input/output | File input/output is part of Short Circuit's Console Program Basics selection.
Task
Create a file called "output.txt", and place in it the contents of the file "input.txt", via an intermediate variable.
In other words, your program will demonstrate:
how to read from a file into a variable
how to write ... | #IDL | IDL | ; open two LUNs
openw,unit1,'output.txt,/get
openr,unit2,'input.txt',/get
; how many bytes to read
fs = fstat(unit2)
; make buffer
buff = bytarr(fs.size)
; transfer content
readu,unit2,buff
writeu,unit1,buff
; that's all
close,/all |
http://rosettacode.org/wiki/File_input/output | File input/output | File input/output is part of Short Circuit's Console Program Basics selection.
Task
Create a file called "output.txt", and place in it the contents of the file "input.txt", via an intermediate variable.
In other words, your program will demonstrate:
how to read from a file into a variable
how to write ... | #Io | Io | inf := File with("input.txt") openForReading
outf := File with("output.txt") openForUpdating
while(l := inf readLine,
outf write(l, "\n")
)
inf close
outf close
|
http://rosettacode.org/wiki/Fibonacci_word | Fibonacci word | The Fibonacci Word may be created in a manner analogous to the Fibonacci Sequence as described here:
Define F_Word1 as 1
Define F_Word2 as 0
Form F_Word3 as F_Word2 concatenated with F_Word1 i.e.: 01
Form F_Wordn as F_Wordn-1 concatenated with F_wordn-... | #Objeck | Objeck | use Collection;
class FibonacciWord {
function : native : GetEntropy(result : String) ~ Float {
frequencies := IntMap->New();
each(i : result) {
c := result->Get(i);
if(frequencies->Has(c)) {
count := frequencies->Find(c)->As(IntHolder);
count->Set(count->Get() + 1);
}
... |
http://rosettacode.org/wiki/FASTA_format | FASTA format | In bioinformatics, long character strings are often encoded in a format called FASTA.
A FASTA file can contain several strings, each identified by a name marked by a > (greater than) character at the beginning of the line.
Task
Write a program that reads a FASTA file such as:
>Rosetta_Example_1
THERECANBENOSPACE
... | #PureBasic | PureBasic | EnableExplicit
Define Hdl_File.i,
Frm_File.i,
c.c,
header.b
Hdl_File=ReadFile(#PB_Any,"c:\code_pb\rosettacode\data\FASTA_TEST.txt")
If Not IsFile(Hdl_File) : End -1 : EndIf
Frm_File=ReadStringFormat(Hdl_File)
If OpenConsole("FASTA format")
While Not Eof(Hdl_File)
c=ReadCharacter... |
http://rosettacode.org/wiki/FASTA_format | FASTA format | In bioinformatics, long character strings are often encoded in a format called FASTA.
A FASTA file can contain several strings, each identified by a name marked by a > (greater than) character at the beginning of the line.
Task
Write a program that reads a FASTA file such as:
>Rosetta_Example_1
THERECANBENOSPACE
... | #Python | Python | import io
FASTA='''\
>Rosetta_Example_1
THERECANBENOSPACE
>Rosetta_Example_2
THERECANBESEVERAL
LINESBUTTHEYALLMUST
BECONCATENATED'''
infile = io.StringIO(FASTA)
def fasta_parse(infile):
key = ''
for line in infile:
if line.startswith('>'):
if key:
yield key, val
... |
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 ... | #8080_Assembly | 8080 Assembly | FIBNCI: MOV C, A ; C will store the counter
DCR C ; decrement, because we know f(1) already
MVI A, 1
MVI B, 0
LOOP: MOV D, A
ADD B ; A := A + B
MOV B, D
DCR C
JNZ LOOP ; jump if not zero
RET ; return from subroutine |
http://rosettacode.org/wiki/Factors_of_an_integer | Factors of an integer |
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 |... | #ActionScript | ActionScript | function factor(n:uint):Vector.<uint>
{
var factors:Vector.<uint> = new Vector.<uint>();
for(var i:uint = 1; i <= n; i++)
if(n % i == 0)factors.push(i);
return factors;
} |
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)... | #D | D | void main() {
import std.stdio, std.numeric;
[1.0, 1, 1, 1, 0, 0, 0, 0].fft.writeln;
} |
http://rosettacode.org/wiki/Factors_of_a_Mersenne_number | Factors of a Mersenne number | A Mersenne number is a number in the form of 2P-1.
If P is prime, the Mersenne number may be a Mersenne prime
(if P is not prime, the Mersenne number is also not prime).
In the search for Mersenne prime numbers it is advantageous to eliminate exponents by finding a small factor before starting a, potentially lengthy,... | #Clojure | Clojure | (ns mersennenumber
(:gen-class))
(defn m* [p q m]
" Computes (p*q) mod m "
(mod (*' p q) m))
(defn power
"modular exponentiation (i.e. b^e mod m"
[b e m]
(loop [b b, e e, x 1]
(if (zero? e)
x
(if (even? e) (recur (m* b b m) (quot e 2) x)
(recur (m* b b m) (quot e 2) (... |
http://rosettacode.org/wiki/Farey_sequence | Farey sequence | The Farey sequence Fn of order n is the sequence of completely reduced fractions between 0 and 1 which, when in lowest terms, have denominators less than or equal to n, arranged in order of increasing size.
The Farey sequence is sometimes incorrectly called a Farey series.
Each Farey se... | #FreeBASIC | FreeBASIC | ' version 05-04-2017
' compile with: fbc -s console
' TRUE/FALSE are built-in constants since FreeBASIC 1.04
' But we have to define them for older versions.
#Ifndef TRUE
#Define FALSE 0
#Define TRUE Not FALSE
#EndIf
Function farey(n As ULong, descending As Long) As ULong
Dim As Long a, b = 1, c = 1, ... |
http://rosettacode.org/wiki/Fairshare_between_two_and_more | Fairshare between two and more | The Thue-Morse sequence is a sequence of ones and zeros that if two people
take turns in the given order, the first persons turn for every '0' in the
sequence, the second for every '1'; then this is shown to give a fairer, more
equitable sharing of resources. (Football penalty shoot-outs for example, might
not favour t... | #Mathematica_.2F_Wolfram_Language | Mathematica / Wolfram Language | ClearAll[Fairshare]
Fairshare[n_List, b_Integer : 2] := Fairshare[#, b] & /@ n
Fairshare[n_Integer, b_Integer : 2] := Mod[Total[IntegerDigits[n, b]], b]
Fairshare[Range[0, 24], 2]
Fairshare[Range[0, 24], 3]
Fairshare[Range[0, 24], 5]
Fairshare[Range[0, 24], 11] |
http://rosettacode.org/wiki/Fairshare_between_two_and_more | Fairshare between two and more | The Thue-Morse sequence is a sequence of ones and zeros that if two people
take turns in the given order, the first persons turn for every '0' in the
sequence, the second for every '1'; then this is shown to give a fairer, more
equitable sharing of resources. (Football penalty shoot-outs for example, might
not favour t... | #Nim | Nim | import math, strutils
#---------------------------------------------------------------------------------------------------
iterator countInBase(b: Positive): seq[Natural] =
## Yield the successive integers in base "b" as a sequence of digits.
var value = @[Natural 0]
yield value
while true:
# Add ... |
http://rosettacode.org/wiki/Fairshare_between_two_and_more | Fairshare between two and more | The Thue-Morse sequence is a sequence of ones and zeros that if two people
take turns in the given order, the first persons turn for every '0' in the
sequence, the second for every '1'; then this is shown to give a fairer, more
equitable sharing of resources. (Football penalty shoot-outs for example, might
not favour t... | #Perl | Perl | use strict;
use warnings;
use Math::AnyNum qw(sum polymod);
sub fairshare {
my($b, $n) = @_;
sprintf '%3d'x$n, map { sum ( polymod($_, $b, $b )) % $b } 0 .. $n-1;
}
for (<2 3 5 11>) {
printf "%3s:%s\n", $_, fairshare($_, 25);
} |
http://rosettacode.org/wiki/Faulhaber%27s_triangle | Faulhaber's triangle | Named after Johann Faulhaber, the rows of Faulhaber's triangle are the coefficients of polynomials that represent sums of integer powers, which are extracted from Faulhaber's formula:
∑
k
=
1
n
k
p
=
1
p
+
1
∑
j
=
0
p
(
p
+
1
j
)
B
j
n
p
+
1
−
j
{\displaystyle \sum _{k... | #Julia | Julia | function bernoulli(n)
A = Vector{Rational{BigInt}}(undef, n + 1)
for i in 0:n
A[i + 1] = 1 // (i + 1)
for j = i:-1:1
A[j] = j * (A[j] - A[j + 1])
end
end
return n == 1 ? -A[1] : A[1]
end
function faulhabercoeffs(p)
coeffs = Vector{Rational{BigInt}}(undef, p + 1)... |
http://rosettacode.org/wiki/Faulhaber%27s_triangle | Faulhaber's triangle | Named after Johann Faulhaber, the rows of Faulhaber's triangle are the coefficients of polynomials that represent sums of integer powers, which are extracted from Faulhaber's formula:
∑
k
=
1
n
k
p
=
1
p
+
1
∑
j
=
0
p
(
p
+
1
j
)
B
j
n
p
+
1
−
j
{\displaystyle \sum _{k... | #Kotlin | Kotlin | // version 1.1.2
import java.math.BigDecimal
import java.math.MathContext
val mc = MathContext(256)
fun gcd(a: Long, b: Long): Long = if (b == 0L) a else gcd(b, a % b)
class Frac : Comparable<Frac> {
val num: Long
val denom: Long
companion object {
val ZERO = Frac(0, 1)
val ONE = ... |
http://rosettacode.org/wiki/Faulhaber%27s_formula | Faulhaber's formula | In mathematics, Faulhaber's formula, named after Johann Faulhaber, expresses the sum of the p-th powers of the first n positive integers as a (p + 1)th-degree polynomial function of n, the coefficients involving Bernoulli numbers.
Task
Generate the first 10 closed-form expressions, starting with p = 0.
R... | #Mathematica_.2F_Wolfram_Language | Mathematica / Wolfram Language | ClearAll[Faulhaber]
Faulhaber[n_, 0] := n
Faulhaber[n_, p_] := n^(p + 1)/(p + 1) + 1/2 n^p + Sum[BernoulliB[k]/k! p!/(p - k + 1)! n^(p - k + 1), {k, 2, p}]
Table[{p, Faulhaber[n, p]}, {p, 0, 9}] // Grid |
http://rosettacode.org/wiki/Fibonacci_n-step_number_sequences | Fibonacci n-step number sequences | These number series are an expansion of the ordinary Fibonacci sequence where:
For
n
=
2
{\displaystyle n=2}
we have the Fibonacci sequence; with initial values
[
1
,
1
]
{\displaystyle [1,1]}
and
F
k
2
=
F
k
−
1
2
+
F
k
−
2
2
{\displaystyle F_{k}^{2}=F_{k-1}^{2}+F_{k-2}^{2}}
... | #Common_Lisp | Common Lisp |
(defun gen-fib (lst m)
"Return the first m members of a generalized Fibonacci sequence using lst as initial values
and the length of lst as step."
(let ((l (- (length lst) 1)))
(do* ((fib-list (reverse lst) (cons (loop for i from 0 to l sum (nth i fib-list)) fib-list))
(c (+ l 2) (+ c 1)))
((... |
http://rosettacode.org/wiki/Find_common_directory_path | Find common directory path | Create a routine that, given a set of strings representing directory paths and a single character directory separator, will return a string representing that part of the directory tree that is common to all the directories.
Test your routine using the forward slash '/' character as the directory separator and the foll... | #Python | Python | >>> import os
>>> os.path.commonpath(['/home/user1/tmp/coverage/test',
'/home/user1/tmp/covert/operator', '/home/user1/tmp/coven/members'])
'/home/user1/tmp' |
http://rosettacode.org/wiki/Find_common_directory_path | Find common directory path | Create a routine that, given a set of strings representing directory paths and a single character directory separator, will return a string representing that part of the directory tree that is common to all the directories.
Test your routine using the forward slash '/' character as the directory separator and the foll... | #R | R |
get_common_dir <- function(paths, delim = "/")
{
path_chunks <- strsplit(paths, delim)
i <- 1
repeat({
current_chunk <- sapply(path_chunks, function(x) x[i])
if(any(current_chunk != current_chunk[1])) break
i <- i + 1
})
paste(path_chunks[[1]][seq_len(i - 1)], collapse = delim)
}
# Example... |
http://rosettacode.org/wiki/Filter | Filter | Task
Select certain elements from an Array into a new Array in a generic way.
To demonstrate, select all even numbers from an Array.
As an option, give a second solution which filters destructively,
by modifying the original Array rather than creating a new Array.
| #Elena | Elena | import system'routines;
import system'math;
import extensions;
import extensions'routines;
public program()
{
auto array := new int[]{1,2,3,4,5};
var evens := array.filterBy:(n => n.mod:2 == 0).toArray();
evens.forEach:printingLn
} |
http://rosettacode.org/wiki/Find_limit_of_recursion | Find limit of recursion | Find limit of recursion is part of Short Circuit's Console Program Basics selection.
Task
Find the limit of recursion.
| #TSE_SAL | TSE SAL |
// library: program: run: recursion: limit <description>will stop at 3616</description> <version>1.0.0.0.3</version> <version control></version control> (filenamemacro=runprrli.s) [kn, ri, su, 25-12-2011 23:12:02]
PROC PROCProgramRunRecursionLimit( INTEGER I )
Message( I )
PROCProgramRunRecursionLimit( I + 1 )
END
... |
http://rosettacode.org/wiki/Find_limit_of_recursion | Find limit of recursion | Find limit of recursion is part of Short Circuit's Console Program Basics selection.
Task
Find the limit of recursion.
| #TXR | TXR | (set-sig-handler sig-segv
(lambda (signal async-p) (throw 'out)))
(defvar *count* 0)
(defun recurse ()
(inc *count*)
(recurse))
(catch (recurse)
(out () (put-line `caught segfault!\nreached depth: @{*count*}`))) |
http://rosettacode.org/wiki/Find_limit_of_recursion | Find limit of recursion | Find limit of recursion is part of Short Circuit's Console Program Basics selection.
Task
Find the limit of recursion.
| #UNIX_Shell | UNIX Shell | recurse()
{
# since the example runs slowly, the following
# if-elif avoid unuseful output; the elif was
# added after a first run ended with a segmentation
# fault after printing "10000"
if [[ $(($1 % 5000)) -eq 0 ]]; then
echo $1;
elif [[ $1 -gt 10000 ]]; then
echo $1
fi
recurse $(($1 + 1... |
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)
... | #Hoon | Hoon | :- %say
|= [^ ~ ~]
:- %noun
%+ turn (gulf [1 101])
|= a=@
=+ q=[=(0 (mod a 3)) =(0 (mod a 5))]
?+ q <a>
[& &] "FizzBuzz"
[& |] "Fizz"
[| &] "Buzz"
== |
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.
| #RapidQ | RapidQ | $INCLUDE "rapidq.inc"
DIM file AS QFileStream
FUNCTION fileSize(name$) AS Integer
file.Open(name$, fmOpenRead)
Result = file.Size
file.Close
END FUNCTION
PRINT "Size of input.txt is "; fileSize("input.txt")
PRINT "Size of \input.txt is "; fileSize("\input.txt") |
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.
| #Raven | Raven | 'input.txt' status.size
'/input.txt' status.size |
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.
| #REBOL | REBOL | size? %info.txt
size? %/info.txt
size? ftp://username:password@ftp.site.com/info.txt
size? http://rosettacode.org |
http://rosettacode.org/wiki/File_input/output | File input/output | File input/output is part of Short Circuit's Console Program Basics selection.
Task
Create a file called "output.txt", and place in it the contents of the file "input.txt", via an intermediate variable.
In other words, your program will demonstrate:
how to read from a file into a variable
how to write ... | #J | J | 'output.txt' (1!:2~ 1!:1)&< 'input.txt' |
http://rosettacode.org/wiki/File_input/output | File input/output | File input/output is part of Short Circuit's Console Program Basics selection.
Task
Create a file called "output.txt", and place in it the contents of the file "input.txt", via an intermediate variable.
In other words, your program will demonstrate:
how to read from a file into a variable
how to write ... | #Java | Java | import java.io.*;
public class FileIODemo {
public static void main(String[] args) {
try {
FileInputStream in = new FileInputStream("input.txt");
FileOutputStream out = new FileOutputStream("ouput.txt");
int c;
while ((c = in.read()) != -1) {
out.write(c);
}
} catch (Fi... |
http://rosettacode.org/wiki/Fibonacci_word | Fibonacci word | The Fibonacci Word may be created in a manner analogous to the Fibonacci Sequence as described here:
Define F_Word1 as 1
Define F_Word2 as 0
Form F_Word3 as F_Word2 concatenated with F_Word1 i.e.: 01
Form F_Wordn as F_Wordn-1 concatenated with F_wordn-... | #Oforth | Oforth | : entropy(s) -- f
| freq sz |
s size dup ifZero: [ return ] asFloat ->sz
ListBuffer initValue(255, 0) ->freq
s apply( #[ dup freq at 1+ freq put ] )
0.0 freq applyIf( #[ 0 <> ], #[ sz / dup ln * - ] ) Ln2 / ;
: FWords(n)
| ws i |
ListBuffer new dup add("1") dup add("0") dup ->ws
3 n for: i [ i 1- ... |
http://rosettacode.org/wiki/Fibonacci_word | Fibonacci word | The Fibonacci Word may be created in a manner analogous to the Fibonacci Sequence as described here:
Define F_Word1 as 1
Define F_Word2 as 0
Form F_Word3 as F_Word2 concatenated with F_Word1 i.e.: 01
Form F_Wordn as F_Wordn-1 concatenated with F_wordn-... | #ooRexx | ooRexx | /* REXX ---------------------------------------------------------------
* 09.08.2014 Walter Pachl 'copied' from REXX
* lists the # of chars in fibonacci words and the words' entropy
* as well as (part of) the Fibonacci word and the number of 0's and 1's
* Note: ooRexx allows for computing up to 47 Fibonacci words
*----... |
http://rosettacode.org/wiki/FASTA_format | FASTA format | In bioinformatics, long character strings are often encoded in a format called FASTA.
A FASTA file can contain several strings, each identified by a name marked by a > (greater than) character at the beginning of the line.
Task
Write a program that reads a FASTA file such as:
>Rosetta_Example_1
THERECANBENOSPACE
... | #R | R |
library("seqinr")
data <- c(">Rosetta_Example_1","THERECANBENOSPACE",">Rosetta_Example_2","THERECANBESEVERAL","LINESBUTTHEYALLMUST","BECONCATENATED")
fname <- "rosettacode.fasta"
f <- file(fname,"w+")
writeLines(data,f)
close(f)
fasta <- read.fasta(file = fname, as.string = TRUE, seqtype = "AA")
for (aline in fas... |
http://rosettacode.org/wiki/FASTA_format | FASTA format | In bioinformatics, long character strings are often encoded in a format called FASTA.
A FASTA file can contain several strings, each identified by a name marked by a > (greater than) character at the beginning of the line.
Task
Write a program that reads a FASTA file such as:
>Rosetta_Example_1
THERECANBENOSPACE
... | #Racket | Racket |
#lang racket
(let loop ([m #t])
(when m
(when (regexp-try-match #rx"^>" (current-input-port))
(unless (eq? #t m) (newline))
(printf "~a: " (read-line)))
(loop (regexp-match #rx"\n" (current-input-port) 0 #f
(current-output-port)))))
(newline)
|
http://rosettacode.org/wiki/FASTA_format | FASTA format | In bioinformatics, long character strings are often encoded in a format called FASTA.
A FASTA file can contain several strings, each identified by a name marked by a > (greater than) character at the beginning of the line.
Task
Write a program that reads a FASTA file such as:
>Rosetta_Example_1
THERECANBENOSPACE
... | #Raku | Raku | grammar FASTA {
rule TOP { <entry>+ }
rule entry { \> <title> <sequence> }
token title { <.alnum>+ }
token sequence { ( <.alnum>+ )+ % \n { make $0.join } }
}
FASTA.parse: q:to /§/;
>Rosetta_Example_1
THERECANBENOSPACE
>Rosetta_Example_2
THERECANBESEVERAL
LINESBUTTHEYALLMUST
BECONCATENATED
§
... |
http://rosettacode.org/wiki/Fibonacci_sequence | Fibonacci sequence | The Fibonacci sequence is a sequence Fn of natural numbers defined recursively:
F0 = 0
F1 = 1
Fn = Fn-1 + Fn-2, if n>1
Task
Write a function to generate the nth Fibonacci number.
Solutions can be iterative or recursive (though recursive solutions are generally considered too slow ... | #8086_Assembly | 8086 Assembly | fib:
; WRITTEN IN C WITH X86-64 CLANG 3.3 AND DOWNGRADED TO 16-BIT X86
; INPUT: DI = THE NUMBER YOU WISH TO CALC THE FIBONACCI NUMBER FOR.
; OUTPUTS TO AX
push BP
push BX
push AX
mov BX, DI ;COPY INPUT TO BX
xor AX, AX ;MOV AX,0
test BX, BX ;... |
http://rosettacode.org/wiki/Factors_of_an_integer | Factors of an integer |
Basic Data Operation
This is a basic data operation. It represents a fundamental action on a basic data type.
You may see other such operations in the Basic Data Operations category, or:
Integer Operations
Arithmetic |
Comparison
Boolean Operations
Bitwise |
Logical
String Operations
Concatenation |
Interpolation |... | #Ada | Ada | with Ada.Text_IO;
with Ada.Command_Line;
procedure Factors is
Number : Positive;
Test_Nr : Positive := 1;
begin
if Ada.Command_Line.Argument_Count /= 1 then
Ada.Text_IO.Put (Ada.Text_IO.Standard_Error, "Missing argument!");
Ada.Command_Line.Set_Exit_Status (Ada.Command_Line.Failure);
return;... |
http://rosettacode.org/wiki/Fast_Fourier_transform | Fast Fourier transform | Task
Calculate the FFT (Fast Fourier Transform) of an input sequence.
The most general case allows for complex numbers at the input
and results in a sequence of equal length, again of complex numbers.
If you need to restrict yourself to real numbers, the output should
be the magnitude (i.e.: sqrt(re2 + im2)... | #Delphi | Delphi |
program Fast_Fourier_transform;
{$APPTYPE CONSOLE}
uses
System.SysUtils,
System.VarCmplx,
System.Math;
function BitReverse(n: UInt64; bits: Integer): UInt64;
var
count, reversedN: UInt64;
begin
reversedN := n;
count := bits - 1;
n := n shr 1;
while n > 0 do
begin
reversedN := (reversed... |
http://rosettacode.org/wiki/Factors_of_a_Mersenne_number | Factors of a Mersenne number | A Mersenne number is a number in the form of 2P-1.
If P is prime, the Mersenne number may be a Mersenne prime
(if P is not prime, the Mersenne number is also not prime).
In the search for Mersenne prime numbers it is advantageous to eliminate exponents by finding a small factor before starting a, potentially lengthy,... | #CoffeeScript | CoffeeScript | mersenneFactor = (p) ->
limit = Math.sqrt(Math.pow(2,p) - 1)
k = 1
while (2*k*p - 1) < limit
q = 2*k*p + 1
if isPrime(q) and (q % 8 == 1 or q % 8 == 7) and trialFactor(2,p,q)
return q
k++
return null
isPrime = (value) ->
for i in [2...value]
return false... |
http://rosettacode.org/wiki/Farey_sequence | Farey sequence | The Farey sequence Fn of order n is the sequence of completely reduced fractions between 0 and 1 which, when in lowest terms, have denominators less than or equal to n, arranged in order of increasing size.
The Farey sequence is sometimes incorrectly called a Farey series.
Each Farey se... | #FunL | FunL | def farey( n ) =
res = seq()
a, b, c, d = 0, 1, 1, n
res += "$a/$b"
while c <= n
k = (n + b)\d
a, b, c, d = c, d, k*c - a, k*d - b
res += "$a/$b"
for i <- 1..11
println( "$i: ${farey(i).mkString(', ')}" )
for i <- 100..1000 by 100
println( "$i: ${farey(i).length()}" ) |
http://rosettacode.org/wiki/Farey_sequence | Farey sequence | The Farey sequence Fn of order n is the sequence of completely reduced fractions between 0 and 1 which, when in lowest terms, have denominators less than or equal to n, arranged in order of increasing size.
The Farey sequence is sometimes incorrectly called a Farey series.
Each Farey se... | #F.C5.8Drmul.C3.A6 | Fōrmulæ | package main
import "fmt"
type frac struct{ num, den int }
func (f frac) String() string {
return fmt.Sprintf("%d/%d", f.num, f.den)
}
func f(l, r frac, n int) {
m := frac{l.num + r.num, l.den + r.den}
if m.den <= n {
f(l, m, n)
fmt.Print(m, " ")
f(m, r, n)
}
}
func mai... |
http://rosettacode.org/wiki/Fairshare_between_two_and_more | Fairshare between two and more | The Thue-Morse sequence is a sequence of ones and zeros that if two people
take turns in the given order, the first persons turn for every '0' in the
sequence, the second for every '1'; then this is shown to give a fairer, more
equitable sharing of resources. (Football penalty shoot-outs for example, might
not favour t... | #Phix | Phix | function fairshare(integer n, base)
sequence res = repeat(0,n)
for i=1 to n do
integer j = i-1,
t = 0
while j>0 do
t += remainder(j,base)
j = floor(j/base)
end while
res[i] = remainder(t,base)
end for
return {base,res}
end function
... |
http://rosettacode.org/wiki/Fairshare_between_two_and_more | Fairshare between two and more | The Thue-Morse sequence is a sequence of ones and zeros that if two people
take turns in the given order, the first persons turn for every '0' in the
sequence, the second for every '1'; then this is shown to give a fairer, more
equitable sharing of resources. (Football penalty shoot-outs for example, might
not favour t... | #Python | Python | from itertools import count, islice
def _basechange_int(num, b):
"""
Return list of ints representing positive num in base b
>>> b = 3
>>> print(b, [_basechange_int(num, b) for num in range(11)])
3 [[0], [1], [2], [1, 0], [1, 1], [1, 2], [2, 0], [2, 1], [2, 2], [1, 0, 0], [1, 0, 1]]
>>>
... |
http://rosettacode.org/wiki/Faulhaber%27s_triangle | Faulhaber's triangle | Named after Johann Faulhaber, the rows of Faulhaber's triangle are the coefficients of polynomials that represent sums of integer powers, which are extracted from Faulhaber's formula:
∑
k
=
1
n
k
p
=
1
p
+
1
∑
j
=
0
p
(
p
+
1
j
)
B
j
n
p
+
1
−
j
{\displaystyle \sum _{k... | #Lua | Lua | function binomial(n,k)
if n<0 or k<0 or n<k then return -1 end
if n==0 or k==0 then return 1 end
local num = 1
for i=k+1,n do
num = num * i
end
local denom = 1
for i=2,n-k do
denom = denom * i
end
return num / denom
end
function gcd(a,b)
while b ~= 0 do
... |
http://rosettacode.org/wiki/Faulhaber%27s_formula | Faulhaber's formula | In mathematics, Faulhaber's formula, named after Johann Faulhaber, expresses the sum of the p-th powers of the first n positive integers as a (p + 1)th-degree polynomial function of n, the coefficients involving Bernoulli numbers.
Task
Generate the first 10 closed-form expressions, starting with p = 0.
R... | #Maxima | Maxima | sum1(p):=sum(stirling2(p,k)*pochhammer(n-k+1,k+1)/(k+1),k,0,p)$
sum2(p):=sum((-1)^j*binomial(p+1,j)*bern(j)*n^(p-j+1),j,0,p)/(p+1)$
makelist(expand(sum1(p)-sum2(p)),p,1,10);
[0,0,0,0,0,0,0,0,0,0]
for p from 0 thru 9 do print(expand(sum2(p))); |
http://rosettacode.org/wiki/Fibonacci_n-step_number_sequences | Fibonacci n-step number sequences | These number series are an expansion of the ordinary Fibonacci sequence where:
For
n
=
2
{\displaystyle n=2}
we have the Fibonacci sequence; with initial values
[
1
,
1
]
{\displaystyle [1,1]}
and
F
k
2
=
F
k
−
1
2
+
F
k
−
2
2
{\displaystyle F_{k}^{2}=F_{k-1}^{2}+F_{k-2}^{2}}
... | #D | D | void main() {
import std.stdio, std.algorithm, std.range, std.conv;
const(int)[] memo;
size_t addNum;
void setHead(int[] head) nothrow @safe {
memo = head;
addNum = head.length;
}
int fibber(in size_t n) nothrow @safe {
if (n >= memo.length)
memo ~= iota... |
http://rosettacode.org/wiki/Find_common_directory_path | Find common directory path | Create a routine that, given a set of strings representing directory paths and a single character directory separator, will return a string representing that part of the directory tree that is common to all the directories.
Test your routine using the forward slash '/' character as the directory separator and the foll... | #Racket | Racket |
#lang racket
(define (common-directory path . paths)
(string-join
(let loop ([path (string-split path "/" #:trim? #f)]
[paths (map (λ(p) (string-split p "/" #:trim? #f)) paths)])
(if (and (pair? path)
(andmap (λ(p) (and (pair? p) (equal? (car p) (car path))))
... |
http://rosettacode.org/wiki/Find_common_directory_path | Find common directory path | Create a routine that, given a set of strings representing directory paths and a single character directory separator, will return a string representing that part of the directory tree that is common to all the directories.
Test your routine using the forward slash '/' character as the directory separator and the foll... | #Raku | Raku | my $sep = '/';
my @dirs = </home/user1/tmp/coverage/test
/home/user1/tmp/covert/operator
/home/user1/tmp/coven/members>;
my @comps = @dirs.map: { [ .comb(/ $sep [ <!before $sep> . ]* /) ] };
my $prefix = '';
while all(@comps[*]»[0]) eq @comps[0][0] {
$prefix ~= @comps[0][0] // last;
... |
http://rosettacode.org/wiki/Filter | Filter | Task
Select certain elements from an Array into a new Array in a generic way.
To demonstrate, select all even numbers from an Array.
As an option, give a second solution which filters destructively,
by modifying the original Array rather than creating a new Array.
| #Elixir | Elixir | iex(10)> numbers = Enum.to_list(1..9)
[1, 2, 3, 4, 5, 6, 7, 8, 9]
iex(11)> Enum.filter(numbers, fn x -> rem(x,2)==0 end)
[2, 4, 6, 8]
iex(12)> for x <- numbers, rem(x,2)==0, do: x # comprehension
[2, 4, 6, 8] |
http://rosettacode.org/wiki/Find_limit_of_recursion | Find limit of recursion | Find limit of recursion is part of Short Circuit's Console Program Basics selection.
Task
Find the limit of recursion.
| #Ursa | Ursa | def recurse (int counter)
try
recurse (+ counter 1)
catch recursionerror
out "the limit of recursion was " counter endl console
end try
end
recurse 1 |
http://rosettacode.org/wiki/Find_limit_of_recursion | Find limit of recursion | Find limit of recursion is part of Short Circuit's Console Program Basics selection.
Task
Find the limit of recursion.
| #Vala | Vala | void recur(uint64 v ) {
print (@"$v\n");
recur( v + 1);
}
void main() {
recur(0);
} |
http://rosettacode.org/wiki/Find_limit_of_recursion | Find limit of recursion | Find limit of recursion is part of Short Circuit's Console Program Basics selection.
Task
Find the limit of recursion.
| #VBA | VBA |
Option Explicit
Sub Main()
Debug.Print "The limit is : " & Limite_Recursivite(0)
End Sub
Function Limite_Recursivite(Cpt As Long) As Long
Cpt = Cpt + 1 'Count
On Error Resume Next
Limite_Recursivite Cpt 'recurse
On Error GoTo 0
Limite_Recursivite = Cpt 'return
End Fun... |
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)
... | #Huginn | Huginn | import Algorithms as algo;
main( argv_ ) {
if ( size( argv_ ) < 2 ) {
throw Exception( "usage: fizzbuzz {NUM}" );
}
top = integer( argv_[1] );
for ( i : algo.range( 1, top + 1 ) ) {
by3 = ( i % 3 ) == 0;
by5 = ( i % 5 ) == 0;
if ( by3 ) {
print( "fizz" );
}
if ( by5 ) {
print( "buzz" );
}
if... |
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.
| #Red | Red | >> size? %input.txt
== 39244
>> size? %/c/input.txt
== 39244 |
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.
| #Retro | Retro | with files'
"input.txt" :R open &size sip close drop putn
"/input.txt" :R open &size sip close drop putn |
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.
| #REXX | REXX | /*REXX program determines a file's size (by reading all the data) in current dir & root.*/
parse arg iFID . /*allow the user specify the file ID. */
if iFID=='' | iFID=="," then iFID='input.txt' /*Not specified? Then use the default.*/
say 'size of 'iFID "=" fSize(iFID) ... |
http://rosettacode.org/wiki/File_input/output | File input/output | File input/output is part of Short Circuit's Console Program Basics selection.
Task
Create a file called "output.txt", and place in it the contents of the file "input.txt", via an intermediate variable.
In other words, your program will demonstrate:
how to read from a file into a variable
how to write ... | #JavaScript | JavaScript | var fso = new ActiveXObject("Scripting.FileSystemObject");
var ForReading = 1, ForWriting = 2;
var f_in = fso.OpenTextFile('input.txt', ForReading);
var f_out = fso.OpenTextFile('output.txt', ForWriting, true);
// for small files:
// f_out.Write( f_in.ReadAll() );
while ( ! f_in.AtEndOfStream) {
// ReadLine() ... |
http://rosettacode.org/wiki/File_input/output | File input/output | File input/output is part of Short Circuit's Console Program Basics selection.
Task
Create a file called "output.txt", and place in it the contents of the file "input.txt", via an intermediate variable.
In other words, your program will demonstrate:
how to read from a file into a variable
how to write ... | #jq | jq | jq -M --raw-input --raw-output '. as $line | $line' input.txt > output.txt
|
http://rosettacode.org/wiki/Fibonacci_word | Fibonacci word | The Fibonacci Word may be created in a manner analogous to the Fibonacci Sequence as described here:
Define F_Word1 as 1
Define F_Word2 as 0
Form F_Word3 as F_Word2 concatenated with F_Word1 i.e.: 01
Form F_Wordn as F_Wordn-1 concatenated with F_wordn-... | #PARI.2FGP | PARI/GP | ent(a,b)=[a,b]=[a,b]/(a+b);(a*log(if(a,a,1))+b*log(if(b,b,1)))/log(1/2)
allocatemem(75<<20) \\ Allocate 75 MB stack space
F=vector(37);F[1]="1";F[2]="0";for(n=3,37,F[n]=Str(F[n-1],F[n-2]))
for(n=1,37,print(n" "fibonacci(n)" "ent(fibonacci(n-1),fibonacci(n-2)))) |
http://rosettacode.org/wiki/FASTA_format | FASTA format | In bioinformatics, long character strings are often encoded in a format called FASTA.
A FASTA file can contain several strings, each identified by a name marked by a > (greater than) character at the beginning of the line.
Task
Write a program that reads a FASTA file such as:
>Rosetta_Example_1
THERECANBENOSPACE
... | #REXX | REXX | /*REXX program reads a (bio-informational) FASTA file and displays the contents. */
parse arg iFID . /*iFID: the input file to be read. */
if iFID=='' then iFID='FASTA.IN' /*Not specified? Then use the default.*/
name= ... |
http://rosettacode.org/wiki/FASTA_format | FASTA format | In bioinformatics, long character strings are often encoded in a format called FASTA.
A FASTA file can contain several strings, each identified by a name marked by a > (greater than) character at the beginning of the line.
Task
Write a program that reads a FASTA file such as:
>Rosetta_Example_1
THERECANBENOSPACE
... | #Ring | Ring |
# Project : FAST format
a = ">Rosetta_Example_1
THERECANBENOSPACE
>Rosetta_Example_2
THERECANBESEVERAL
LINESBUTTHEYALLMUST
BECONCATENATED"
i = 1
while i <= len(a)
if substr(a,i,17) = ">Rosetta_Example_"
see nl
see substr(a,i,18) + ": " + nl
i = i + 17
else
if asc... |
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 ... | #8th | 8th |
: fibon \ n -- fib(n)
>r 0 1
( tuck n:+ ) \ fib(n-2) fib(n-1) -- fib(n-1) fib(n)
r> n:1- times ;
: fib \ n -- fib(n)
dup 1 n:= if 1 ;; then
fibon nip ;
|
http://rosettacode.org/wiki/Factors_of_an_integer | Factors of an integer |
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 |... | #Aikido | Aikido | import math
function factor (n:int) {
var result = []
function append (v) {
if (!(v in result)) {
result.append (v)
}
}
var sqrt = cast<int>(Math.sqrt (n))
append (1)
for (var i = n-1 ; i >= sqrt ; i--) {
if ((n % i) == 0) {
append (i)
... |
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