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/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... | #Kotlin | Kotlin | // version 1.1.51
fun findCommonDirPath(paths: List<String>, separator: Char): String {
if (paths.isEmpty()) return ""
if (paths.size == 1) return paths[0]
val splits = paths[0].split(separator)
val n = splits.size
val paths2 = paths.drop(1)
var k = 0
var common = ""
while (true) {
... |
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.
| #C | C | #include <stdio.h>
#include <stdlib.h>
int even_sel(int x) { return !(x & 1); }
int tri_sel(int x) { return x % 3; }
/* using a predicate function sel() to select elements */
int* grep(int *in, int len, int *outlen, int (*sel)(int), int inplace)
{
int i, j, *out;
if (inplace) out = in;
else out = malloc(sizeo... |
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.
| #Neko | Neko | /**
Recursion limit, in Neko
*/
/* This version is effectively unlimited, (50 billion test before ctrl-c) */
sum = 0.0
counter = 0
tco = function(n) {
sum += n
counter += 1
if n > 10000000 return n else tco(n + 1)
}
try $print("Tail call recursion: ", tco(0), " sum: ", sum, "\n")
catch with $print("tco... |
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.
| #NetRexx | NetRexx | /* NetRexx */
options replace format comments java crossref symbols binary
import java.lang.management.
memoryInfo()
digDeeper(0)
/**
* Just keep digging
* @param level depth gauge
*/
method digDeeper(level = int) private static binary
do
digDeeper(level + 1)
catch ex = Error
System.out.println('Re... |
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)
... | #F.C5.8Drmul.C3.A6 | Fōrmulæ | Public Sub Main()
Dim siCount As Short
Dim sText As String
For siCount = 1 To 100
sText = ""
If siCount Mod 3 = 0 Then sText = "Fizz"
If siCount Mod 5 = 0 Then sText = "Buzz"
If siCount Mod 15 = 0 Then sText = "FizzBuzz"
If sText Then Print sText Else Print siCount
Next
End |
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.
| #J | J | require 'files'
fsize 'input.txt';'/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.
| #Java | Java | import java.io.File;
public class FileSize
{
public static void main ( String[] args )
{
System.out.println("input.txt : " + new File("input.txt").length() + " bytes");
System.out.println("/input.txt : " + new File("/input.txt").length() + " bytes");
}
}
|
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 ... | #DBL | DBL | ;
; File Input and output examples for DBL version 4 by Dario B.
;
RECORD CUSTOM
CUCOD, D5 ;customer code
CUNAM, A20 ;name
CUCIT, A20 ;city
, A55
;------- 100 bytes -------------
A80, A80
PROC
;--------------------------------------------------------------
... |
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 ... | #DCL | DCL | $ open input input.txt
$ open /write output output.txt
$ loop:
$ read /end_of_file = done input line
$ write output line
$ goto loop
$ done:
$ close input
$ close output |
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-... | #D | D | import std.stdio, std.algorithm, std.math, std.string, std.range;
real entropy(T)(T[] s) pure nothrow
if (__traits(compiles, s.sort())) {
immutable sLen = s.length;
return s
.sort()
.group
.map!(g => g[1] / real(sLen))
.map!(p => -p * p.log2)
.sum;
}
vo... |
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
... | #BASIC256 | BASIC256 | open 1, "input.fasta"
first = True
while not eof(1)
ln = readline(1)
if left(ln, 1) = ">" then
if not first then print
print mid(ln, 2, length(ln)-2) & ": ";
if first then first = False
else
if first then
print "Error : File does not begin with '>'"
... |
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
... | #C | C | #include <stdio.h>
#include <stdlib.h>
#include <string.h>
void main()
{
FILE * fp;
char * line = NULL;
size_t len = 0;
ssize_t read;
fp = fopen("fasta.txt", "r");
if (fp == NULL)
exit(EXIT_FAILURE);
int state = 0;
while ((read = getline(&line, &len, fp)) != -1) {
/* Delete trailing newline */
if (l... |
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... | #C.23 | C# | using System;
namespace FaulhabersFormula {
internal class Frac {
private long num;
private long denom;
public static readonly Frac ZERO = new Frac(0, 1);
public static readonly Frac ONE = new Frac(1, 1);
public Frac(long n, long d) {
if (d == 0) {
... |
http://rosettacode.org/wiki/Fermat_numbers | Fermat numbers | In mathematics, a Fermat number, named after Pierre de Fermat who first studied them, is a positive integer of the form Fn = 22n + 1 where n is a non-negative integer.
Despite the simplicity of generating Fermat numbers, they have some powerful mathematical properties and are extensively used in cryptography & pseudo-... | #Kotlin | Kotlin | import java.math.BigInteger
import kotlin.math.pow
fun main() {
println("First 10 Fermat numbers:")
for (i in 0..9) {
println("F[$i] = ${fermat(i)}")
}
println()
println("First 12 Fermat numbers factored:")
for (i in 0..12) {
println("F[$i] = ${getString(getFactors(i, fermat(i)... |
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}}
... | #APL | APL | nStep ← {⊃(1↓⊢,+/)⍣(⍺-1)⊢⍵}
nacci ← 2*0⌈¯2+⍳
↑((⍳10)nStep¨⊂)¨(nacci¨2 3 4),⊂2 1 |
http://rosettacode.org/wiki/Feigenbaum_constant_calculation | Feigenbaum constant calculation | Task
Calculate the Feigenbaum constant.
See
Details in the Wikipedia article: Feigenbaum constant.
| #jq | jq | def feigenbaum_delta(imax; jmax):
def lpad: tostring | (" " * (4 - length)) + .;
def pp(i;x): "\(i|lpad) \(x)";
"Feigenbaum's delta constant incremental calculation:",
pp("i"; "δ"),
pp(1; "3.20"),
( foreach range(2; 1+imax) as $i (
{a1: 1.0, a2: 0.0, d1: 3.2};
.a = .a1 + (.... |
http://rosettacode.org/wiki/Feigenbaum_constant_calculation | Feigenbaum constant calculation | Task
Calculate the Feigenbaum constant.
See
Details in the Wikipedia article: Feigenbaum constant.
| #Julia | Julia | # http://en.wikipedia.org/wiki/Feigenbaum_constant
function feigenbaum_delta(imax=23, jmax=20)
a1, a2, d1 = BigFloat(1.0), BigFloat(0.0), BigFloat(3.2)
println("Feigenbaum's delta constant incremental calculation:\ni δ\n1 3.20")
for i in 2:imax
a = a1 + (a1 - a2) / d1
for j in 1:jmax
... |
http://rosettacode.org/wiki/Feigenbaum_constant_calculation | Feigenbaum constant calculation | Task
Calculate the Feigenbaum constant.
See
Details in the Wikipedia article: Feigenbaum constant.
| #Kotlin | Kotlin | // Version 1.2.40
fun feigenbaum() {
val maxIt = 13
val maxItJ = 10
var a1 = 1.0
var a2 = 0.0
var d1 = 3.2
println(" i d")
for (i in 2..maxIt) {
var a = a1 + (a1 - a2) / d1
for (j in 1..maxItJ) {
var x = 0.0
var y = 0.0
for (k in 1.... |
http://rosettacode.org/wiki/File_extension_is_in_extensions_list | File extension is in extensions list | File extension is in extensions list
You are encouraged to solve this task according to the task description, using any language you may know.
Filename extensions are a rudimentary but commonly used way of identifying files types.
Task
Given an arbitrary filename and a list of extensions, tell whether the filename... | #Perl | Perl | sub check_extension {
my ($filename, @extensions) = @_;
my $extensions = join '|', map quotemeta, @extensions;
scalar $filename =~ / \. (?: $extensions ) $ /xi
} |
http://rosettacode.org/wiki/File_extension_is_in_extensions_list | File extension is in extensions list | File extension is in extensions list
You are encouraged to solve this task according to the task description, using any language you may know.
Filename extensions are a rudimentary but commonly used way of identifying files types.
Task
Given an arbitrary filename and a list of extensions, tell whether the filename... | #PHP | PHP |
$allowed = ['zip', 'rar', '7z', 'gz', 'archive', 'A##', 'tar.bz2'];
$lc_allowed = array_map('strtolower', $allowed);
$tests = [
['MyData.a##',true],
['MyData.tar.Gz',true],
['MyData.gzip',false],
['MyData.7z.backup',false],
['MyData...',false],
['MyData',false],
['archive.tar.gz', true]
... |
http://rosettacode.org/wiki/File_modification_time | File modification time | Task
Get and set the modification time of a file.
| #OCaml | OCaml | #load "unix.cma";;
open Unix;;
let mtime = (stat filename).st_mtime;; (* seconds since the epoch *)
utimes filename (stat filename).st_atime (time ());;
(* keep atime unchanged
set mtime to current time *) |
http://rosettacode.org/wiki/File_modification_time | File modification time | Task
Get and set the modification time of a file.
| #Oforth | Oforth | File new("myfile.txt") modified |
http://rosettacode.org/wiki/File_modification_time | File modification time | Task
Get and set the modification time of a file.
| #OpenEdge.2FProgress | OpenEdge/Progress | FILE-INFO:FILE-NAME = 'c:/temp'.
MESSAGE
STRING( FILE-INFO:FILE-MOD-TIME, 'HH:MM:SS' )
VIEW-AS ALERT-BOX |
http://rosettacode.org/wiki/Fibonacci_word/fractal | Fibonacci word/fractal |
The Fibonacci word may be represented as a fractal as described here:
(Clicking on the above website (hal.archives-ouvertes.fr) will leave a cookie.)
For F_wordm start with F_wordCharn=1
Draw a segment forward
If current F_wordChar is 0
Turn left if n is even
Turn right if n is odd
next n and iterate until e... | #PARI.2FGP | PARI/GP |
\\ Fibonacci word/fractals
\\ 4/25/16 aev
fibword(n)={
my(f1="1",f2="0",fw,fwn,n2);
if(n<=4, n=5);n2=n-2;
for(i=1,n2, fw=Str(f2,f1); f1=f2;f2=fw;); fwn=#fw;
fw=Vecsmall(fw);
for(i=1,fwn,fw[i]-=48);
return(fw);
}
nextdir(n,d)={
my(dir=-1);
if(d==0, if(n%2==0, dir=0,dir=1)); \\0-left,1-right
return(dir);
}
plotfibo... |
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... | #Lasso | Lasso | #!/usr/bin/lasso9
local(
path1 = '/home/user1/tmp/coverage/test' -> split('/'),
path2 = '/home/user1/tmp/covert/operator' -> split('/'),
path3 = '/home/user1/tmp/coven/members' -> split('/')
)
define commonpath(...) => {
local(shared = #rest -> get(1))
loop(#rest -> size - 1) => {
#shared = #shared -> inters... |
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... | #Liberty_BASIC | Liberty BASIC | path$(1) = "/home/user1/tmp/coverage/test"
path$(2) = "/home/user1/tmp/covert/operator"
path$(3) = "/home/user1/tmp/coven/members"
print samepath$(3,"/")
end
function samepath$(paths,sep$)
d = 1 'directory depth
n = 2 'path$(number)
while 1
if word$(path$(1),d,sep$) <> word$(path$(n),d,sep$) o... |
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.
| #C.23 | C# | ArrayList array = new ArrayList( new int[] { 1, 2, 3, 4, 5 } );
ArrayList evens = new ArrayList();
foreach( int i in array )
{
if( (i%2) == 0 )
evens.Add( i );
}
foreach( int i in evens )
System.Console.WriteLine( i.ToString() ); |
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.
| #Nim | Nim | proc recurse(i: int): int =
echo i
recurse(i+1)
echo 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.
| #OCaml | OCaml | # let last = ref 0 ;;
val last : int ref = {contents = 0}
# let rec f i =
last := i;
i + (f (i+1))
;;
val f : int -> int = <fun>
# f 0 ;;
stack overflow during evaluation (looping recursion?).
# !last ;;
- : int = 262067 |
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)
... | #Gambas | Gambas | Public Sub Main()
Dim siCount As Short
Dim sText As String
For siCount = 1 To 100
sText = ""
If siCount Mod 3 = 0 Then sText = "Fizz"
If siCount Mod 5 = 0 Then sText = "Buzz"
If siCount Mod 15 = 0 Then sText = "FizzBuzz"
If sText Then Print sText Else Print siCount
Next
End |
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.
| #JavaScript | JavaScript | var fso = new ActiveXObject("Scripting.FileSystemObject");
fso.GetFile('input.txt').Size;
fso.GetFile('c:/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.
| #jq | jq | jq -Rs length input.txt
jq -Rs length /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.
| #Julia | Julia | println(filesize("input.txt"))
println(filesize("/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 ... | #Delphi | Delphi | - Read(F,V1..Vn)
- ReadLn(F,V1..Vn)
- Write(F,V1[,V2..Vn])
- WriteLn(f,V1[,V2..Vn])
- BlockRead(F,Buff,BytesToRead[,BytesRead])
- BlockWrite(F,Buff,BytesToRead[,BytesWritten])
|
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 ... | #DIBOL-11 | DIBOL-11 |
START ;Simple File Input and Output
RECORD TEMP
INLINE, A72
PROC
OPEN (8,I,"input.txt")
OPEN (9,O,"output.txt")
LOOP,
READS(8,TEMP,END)
WRITES(9,TEMP)
GOTO LOOP
END,
CLOSE 8
CLOSE 9
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-... | #Delphi | Delphi |
(lib 'struct)
(struct FW ( count0 count1 length string)) ;; a fibonacci word
(define (F-word n) ;; generator
(define a (F-word (1- n)))
(define b (F-word (- n 2)))
(FW
(+ (FW-count0 a) (FW-count0 b))
(+ (FW-count1 a) (FW-count1 b))
(+ (FW-length a) (FW-length b))
(if (> n 9... |
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
... | #C.23 | C# | using System;
using System.Collections.Generic;
using System.IO;
using System.Text;
class Program
{
public class FastaEntry
{
public string Name { get; set; }
public StringBuilder Sequence { get; set; }
}
static IEnumerable<FastaEntry> ParseFasta(StreamReader fastaFile)
{
... |
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... | #C | C | #include <stdbool.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
int binomial(int n, int k) {
int num, denom, i;
if (n < 0 || k < 0 || n < k) return -1;
if (n == 0 || k == 0) return 1;
num = 1;
for (i = k + 1; i <= n; ++i) {
num = num * i;
}
denom = 1;
for ... |
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... | #C.2B.2B | C++ | #include <iostream>
#include <numeric>
#include <sstream>
#include <vector>
class Frac {
public:
Frac(long n, long d) {
if (d == 0) {
throw new std::runtime_error("d must not be zero");
}
long nn = n;
long dd = d;
if (nn == 0) {
dd = 1;
} else if (dd < 0) {
nn = -nn;
dd = -dd;
}
long ... |
http://rosettacode.org/wiki/Fermat_numbers | Fermat numbers | In mathematics, a Fermat number, named after Pierre de Fermat who first studied them, is a positive integer of the form Fn = 22n + 1 where n is a non-negative integer.
Despite the simplicity of generating Fermat numbers, they have some powerful mathematical properties and are extensively used in cryptography & pseudo-... | #langur | langur | val .fermat = f 2 ^ 2 ^ .n + 1
val .factors = f(var .x) {
for[.f=[]] .i, .s = 2, truncate .x ^/ 2; .i < .s; .i += 1 {
if .x div .i {
.f ~= [.i]
.x \= .i
.s = truncate .x ^/ 2
}
} ~ [.x]
}
writeln "first 10 Fermat numbers"
for .i in 0..9 {
writeln $"F\(... |
http://rosettacode.org/wiki/Fermat_numbers | Fermat numbers | In mathematics, a Fermat number, named after Pierre de Fermat who first studied them, is a positive integer of the form Fn = 22n + 1 where n is a non-negative integer.
Despite the simplicity of generating Fermat numbers, they have some powerful mathematical properties and are extensively used in cryptography & pseudo-... | #Mathematica_.2F_Wolfram_Language | Mathematica / Wolfram Language | ClearAll[Fermat]
Fermat[n_] := 2^(2^n) + 1
Fermat /@ Range[0, 9]
Scan[FactorInteger /* Print, %] |
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}}
... | #AppleScript | AppleScript | use AppleScript version "2.4"
use framework "Foundation"
use scripting additions
-- Start sequence -> Number of terms -> terms
-- takeNFibs :: [Int] -> Int -> [Int]
on takeNFibs(xs, n)
script go
on |λ|(xs, n)
if 0 < n and 0 < length of xs then
cons(head(xs), ¬
... |
http://rosettacode.org/wiki/Feigenbaum_constant_calculation | Feigenbaum constant calculation | Task
Calculate the Feigenbaum constant.
See
Details in the Wikipedia article: Feigenbaum constant.
| #Lambdatalk | Lambdatalk |
{feigenbaum 11} // on my computer stackoverflow for values greater than 11
-> [3.2185114220380866,4.3856775985683365,4.600949276538056,4.6551304953919646,4.666111947822846,
4.668548581451485,4.66906066077106,4.669171554514976,4.669195154039278,4.669200256503637]
with:
{def feigenbaum
{lambda {:maxi}
{f3 :maxi... |
http://rosettacode.org/wiki/File_extension_is_in_extensions_list | File extension is in extensions list | File extension is in extensions list
You are encouraged to solve this task according to the task description, using any language you may know.
Filename extensions are a rudimentary but commonly used way of identifying files types.
Task
Given an arbitrary filename and a list of extensions, tell whether the filename... | #Phix | Phix | with javascript_semantics
constant extensions = lower({"zip","rar","7z","gz","archive","A##","tar.bz2"})
global function get_known_extension(string filename)
for i=1 to length(filename) do
if filename[i]='.' then
string extension = lower(filename[i+1..$])
if find(extension,extensio... |
http://rosettacode.org/wiki/File_modification_time | File modification time | Task
Get and set the modification time of a file.
| #Oz | Oz | declare
[Path] = {Module.link ['x-oz://system/os/Path.ozf']}
Modified = {Path.mtime "input.txt"} %% posix time
in
{Show {OsTime.localtime Modified}} %% human readable record |
http://rosettacode.org/wiki/File_modification_time | File modification time | Task
Get and set the modification time of a file.
| #Pascal | Pascal | my $mtime = (stat($file))[9]; # seconds since the epoch
# you should use the more legible version below:
use File::stat qw(stat);
my $mtime = stat($file)->mtime; # seconds since the epoch
utime(stat($file)->atime, time, $file);
# keep atime unchanged
# set mtime to current time |
http://rosettacode.org/wiki/Fibonacci_word/fractal | Fibonacci word/fractal |
The Fibonacci word may be represented as a fractal as described here:
(Clicking on the above website (hal.archives-ouvertes.fr) will leave a cookie.)
For F_wordm start with F_wordCharn=1
Draw a segment forward
If current F_wordChar is 0
Turn left if n is even
Turn right if n is odd
next n and iterate until e... | #Perl | Perl | use strict;
use warnings;
use GD;
my @fword = ( undef, 1, 0 );
sub fword {
my $n = shift;
return $fword[$n] if $n<3;
return $fword[$n] //= fword($n-1).fword($n-2);
}
my $size = 3000;
my $im = new GD::Image($size,$size);
my $white = $im->colorAllocate(255,255,255);
my $black = $im->colorAllocate(0,0,0);
... |
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... | #Lingo | Lingo | on getCommonPath (pathes, sep)
_player.itemDelimiter = sep
-- find length of shortest path (in terms of items)
commonCnt = the maxInteger
repeat with p in pathes
if p.item.count<commonCnt then commonCnt=p.item.count
end repeat
pathCnt = pathes.count
repeat with i = 1 to commonCnt
repeat with j... |
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... | #MapBasic | MapBasic | Include "MapBasic.def"
DECLARE SUB Main
DECLARE FUNCTION commonPath(paths() AS STRING, BYVAL pathSep AS STRING) AS STRING
FUNCTION commonPath(paths() AS STRING, BYVAL pathSep AS STRING) AS STRING
DIM tmpint1 AS INTEGER, tmpint2 AS INTEGER, tmpstr1 AS STRING, tmpstr2 AS STRING
DIM L0 AS INTEGER, L1 AS INTEGE... |
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.
| #C.2B.2B | C++ | #include <vector>
#include <algorithm>
#include <functional>
#include <iterator>
#include <iostream>
int main() {
std::vector<int> ary;
for (int i = 0; i < 10; i++)
ary.push_back(i);
std::vector<int> evens;
std::remove_copy_if(ary.begin(), ary.end(), back_inserter(evens),
std::bind2n... |
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.
| #Oforth | Oforth | : limit 1+ dup . limit ;
0 limit |
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.
| #ooRexx | ooRexx | Using ooRexx for the program shown under Rexx:
rexx pgm 1>x1 2>x2
puts the numbers in x1 and the error messages in x2
...
2785
2786
8 *-* call self
....
8 *-* call self
3 *-* call self
Error 11 running C:\work.ooRexx\wc\main.4.1.1.release\Win32Rel\StreamClasses.orx line 366: Control stack full
Er... |
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)
... | #GAP | GAP | FizzBuzz := function()
local i;
for i in [1 .. 100] do
if RemInt(i, 15) = 0 then
Print("FizzBuzz\n");
elif RemInt(i, 3) = 0 then
Print("Fizz\n");
elif RemInt(i, 5) = 0 then
Print("Buzz\n");
else
Print(i, "\n");
fi;
od;
end; |
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.
| #K | K | _size "input.txt"
_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.
| #Kotlin | Kotlin | // version 1.0.6
import java.io.File
fun main(args: Array<String>) {
val paths = arrayOf("input.txt", "c:\\input.txt")
for (path in paths)
println("Length of $path is ${File(path).length()} bytes")
} |
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.
| #Lasso | Lasso | // local to current directory
local(f = file('input.txt'))
handle => { #f->close }
#f->size
// file at file system root
local(f = file('//input.txt'))
handle => { #f->close }
#f->size
|
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 ... | #E | E | <file:output.txt>.setText(<file:input.txt>.getText()) |
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 ... | #Eiffel | Eiffel | class
APPLICATION
create
make
feature {NONE} -- Initialization
make
-- Run application.
do
create input_file.make_open_read ("input.txt")
create output_file.make_open_write ("output.txt")
from
input_file.read_character
... |
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-... | #EchoLisp | EchoLisp |
(lib 'struct)
(struct FW ( count0 count1 length string)) ;; a fibonacci word
(define (F-word n) ;; generator
(define a (F-word (1- n)))
(define b (F-word (- n 2)))
(FW
(+ (FW-count0 a) (FW-count0 b))
(+ (FW-count1 a) (FW-count1 b))
(+ (FW-length a) (FW-length b))
(if (> n 9... |
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
... | #C.2B.2B | C++ | #include <iostream>
#include <fstream>
int main( int argc, char **argv ){
if( argc <= 1 ){
std::cerr << "Usage: "<<argv[0]<<" [infile]" << std::endl;
return -1;
}
std::ifstream input(argv[1]);
if(!input.good()){
std::cerr << "Error opening '"<<argv[1]<<"'. Bailing out." << st... |
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... | #C.23 | C# | using System;
namespace FaulhabersTriangle {
internal class Frac {
private long num;
private long denom;
public static readonly Frac ZERO = new Frac(0, 1);
public static readonly Frac ONE = new Frac(1, 1);
public Frac(long n, long d) {
if (d == 0) {
... |
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... | #D | D | import std.algorithm : fold;
import std.exception : enforce;
import std.format : formattedWrite;
import std.numeric : cmp, gcd;
import std.range : iota;
import std.stdio;
import std.traits;
auto abs(T)(T val)
if (isNumeric!T) {
if (val < 0) {
return -val;
}
return val;
}
struct Frac {
long n... |
http://rosettacode.org/wiki/Fermat_numbers | Fermat numbers | In mathematics, a Fermat number, named after Pierre de Fermat who first studied them, is a positive integer of the form Fn = 22n + 1 where n is a non-negative integer.
Despite the simplicity of generating Fermat numbers, they have some powerful mathematical properties and are extensively used in cryptography & pseudo-... | #Nim | Nim | import math
import bignum
import strformat
import strutils
import tables
import times
const Composite = {9: "5529", 10: "6078", 11: "1037", 12: "5488", 13: "2884"}.toTable
const Subscripts = ["₀", "₁", "₂", "₃", "₄", "₅", "₆", "₇", "₈", "₉"]
let One = newInt(1)
#-------------------------------------------------... |
http://rosettacode.org/wiki/Fermat_numbers | Fermat numbers | In mathematics, a Fermat number, named after Pierre de Fermat who first studied them, is a positive integer of the form Fn = 22n + 1 where n is a non-negative integer.
Despite the simplicity of generating Fermat numbers, they have some powerful mathematical properties and are extensively used in cryptography & pseudo-... | #Perl | Perl | use strict;
use warnings;
use feature 'say';
use bigint try=>"GMP";
use ntheory qw<factor>;
my @Fermats = map { 2**(2**$_) + 1 } 0..9;
my $sub = 0;
say 'First 10 Fermat numbers:';
printf "F%s = %s\n", $sub++, $_ for @Fermats;
$sub = 0;
say "\nFactors of first few Fermat numbers:";
for my $f (map { [factor($_)] } ... |
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}}
... | #AutoHotkey | AutoHotkey | for i, seq in ["nacci", "lucas"]
Loop, 9 {
Out .= seq "(" A_Index + 1 "): "
for key, val in NStepSequence(i, 1, A_Index + 1, 15)
Out .= val (A_Index = 15 ? "`n" : "`, ")
}
MsgBox, % Out
NStepSequence(v1, v2, n, k) {
a := [v1, v2]
Loop, % k - 2 {
a[j := A_Index + 2] ... |
http://rosettacode.org/wiki/Feigenbaum_constant_calculation | Feigenbaum constant calculation | Task
Calculate the Feigenbaum constant.
See
Details in the Wikipedia article: Feigenbaum constant.
| #Lua | Lua | function leftShift(n,p)
local r = n
while p>0 do
r = r * 2
p = p - 1
end
return r
end
-- main
local MAX_IT = 13
local MAX_IT_J = 10
local a1 = 1.0
local a2 = 0.0
local d1 = 3.2
print(" i d")
for i=2,MAX_IT do
local a = a1 + (a1 - a2) / d1
for j=1,MAX_IT_J do
l... |
http://rosettacode.org/wiki/Feigenbaum_constant_calculation | Feigenbaum constant calculation | Task
Calculate the Feigenbaum constant.
See
Details in the Wikipedia article: Feigenbaum constant.
| #Mathematica.2FWolfram_Language | Mathematica/Wolfram Language | maxit = 13;
maxitj = 10;
a1 = 1.0;
a2 = 0.0;
d1 = 3.2;
a = 0.0;
Table[
a = a1 + (a1 - a2)/d1;
Do[
x = 0.0;
y = 0.0;
Do[
y = 1.0 - 2.0 y x;
x = a - x x;
,
{k, 1, 2^i}
];
a = a - x/y
,
{j, maxitj}
];
d = (a1 - a2)/(a - a1);
d1 = d;
a2 = a1;
a1 = a;
{i, d}
,
{i, 2... |
http://rosettacode.org/wiki/File_extension_is_in_extensions_list | File extension is in extensions list | File extension is in extensions list
You are encouraged to solve this task according to the task description, using any language you may know.
Filename extensions are a rudimentary but commonly used way of identifying files types.
Task
Given an arbitrary filename and a list of extensions, tell whether the filename... | #Python | Python |
def isExt(fileName, extensions):
return True in map(fileName.lower().endswith, ("." + e.lower() for e in extensions))
|
http://rosettacode.org/wiki/File_extension_is_in_extensions_list | File extension is in extensions list | File extension is in extensions list
You are encouraged to solve this task according to the task description, using any language you may know.
Filename extensions are a rudimentary but commonly used way of identifying files types.
Task
Given an arbitrary filename and a list of extensions, tell whether the filename... | #Racket | Racket |
#lang racket
(define extensions '(".zip"
".rar"
".7z"
".gz"
".archive"
".a##"
".tar.bz2"))
(define filenames '("MyData.a##"
"MyData.tar.Gz"
"MyData.... |
http://rosettacode.org/wiki/File_modification_time | File modification time | Task
Get and set the modification time of a file.
| #Perl | Perl | my $mtime = (stat($file))[9]; # seconds since the epoch
# you should use the more legible version below:
use File::stat qw(stat);
my $mtime = stat($file)->mtime; # seconds since the epoch
utime(stat($file)->atime, time, $file);
# keep atime unchanged
# set mtime to current time |
http://rosettacode.org/wiki/File_modification_time | File modification time | Task
Get and set the modification time of a file.
| #Phix | Phix | without js -- file i/o
-- (however get as per the JavaScript entry above might be doable if needed)
constant filename = "test.txt"
?get_file_date(filename)
include timedate.e
?format_timedate(get_file_date(filename))
bool res = set_file_date(filename)
?format_timedate(get_file_date(filename))
|
http://rosettacode.org/wiki/Fibonacci_word/fractal | Fibonacci word/fractal |
The Fibonacci word may be represented as a fractal as described here:
(Clicking on the above website (hal.archives-ouvertes.fr) will leave a cookie.)
For F_wordm start with F_wordCharn=1
Draw a segment forward
If current F_wordChar is 0
Turn left if n is even
Turn right if n is odd
next n and iterate until e... | #Phix | Phix | --
-- demo\rosetta\FibonacciFractal.exw
--
with javascript_semantics
include pGUI.e
Ihandle dlg, canvas
cdCanvas cddbuffer, cdcanvas
procedure drawFibonacci(integer x, y, dx, dy, n)
string prev = "1", word = "0"
for i=3 to n do {prev,word} = {word,word&prev} end for
for i=1 to length(word) do
cdCa... |
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... | #Maple | Maple |
dirpath:=proc(a,b,c)
local dirtemp,dirnew,x;
use StringTools in
dirtemp:=LongestCommonSubString(c, LongestCommonSubString(a,b));
x:=FirstFromRight("/",dirtemp);
dirnew:=dirtemp[1..x];
return dirnew;
end use;
end proc;
|
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... | #Mathematica.2FWolfram_Language | Mathematica/Wolfram Language | FindCommonDirectory[x_] := If[StringTake[#, -1] != "/", StringTake[#, Max[StringPosition[#, "/"]]], #] &
[Fold[LongestCommonSubsequence, First[x] , Rest[x]]]
FindCommonDirectory[{"/home/user1/tmp/coverage/test", "/home/user1/tmp/covert/operator", "/home/user1/tmp/coven/members"}]
->"/home/user1/tmp/" |
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.
| #Clean | Clean | module SelectFromArray
import StdEnv |
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.
| #Oz | Oz | declare
proc {Recurse Number}
{Show Number}
{Recurse Number+1}
end
in
{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.
| #PARI.2FGP | PARI/GP | dive(n) = dive(n+1)
dive(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)
... | #Genyris | Genyris |
@prefix u "http://www.genyris.org/lang/utilities#"
def fizzbuzz (n)
map-left ^((3 = 'fizz') (5 = 'buzz'))
lambda (d)
cond
(equal? 0 (% n d!left))
d!right
else
''
for n in (range 1 100)
define fb (''(.join (fizzbu... |
http://rosettacode.org/wiki/File_size | File size | Verify the size of a file called input.txt for a file in the current working directory, and another one in the file system root.
| #Liberty_BASIC | Liberty BASIC | 'input.txt in current directory
OPEN DefaultDir$ + "/input.txt" FOR input AS #m
PRINT "File size: "; lof(#m)
CLOSE #m
'input.txt in root
OPEN "c:/input.txt" FOR input AS #m
PRINT "File size: "; lof(#m)
CLOSE #m |
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.
| #Lingo | Lingo | ----------------------------------------
-- Returns file size
-- @param {string} filename
-- @return {integer}
----------------------------------------
on getFileSize (filename)
fp = xtra("fileIO").new()
fp.openFile(filename, 1)
if fp.status() then return 0
len = fp.getLength()
fp.closeFile()
return len
end |
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.
| #LiveCode | LiveCode | // root folder
set the defaultfolder to "/"
repeat for each line fline in (the detailed files)
if item 1 of fline is "input.txt" then
put item 2 of fline --bytes
exit repeat
end if
end repeat
// current working dir of stack
put the effective filename of this stack into tPath
set the itemDelimi... |
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 ... | #Elena | Elena | import system'io;
public program()
{
var text := File.assign("input.txt").readContent();
File.assign("output.txt").saveContent(text);
} |
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 ... | #Elixir | Elixir | defmodule FileReadWrite do
def copy(path,new_path) do
case File.read(path) do
# In case of success, write to the new file
{:ok, body} ->
# Can replace with :write! to generate an error upon failure
File.write(new_path,body)
# If not successful, raise an error
{:error,reason... |
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-... | #Elixir | Elixir | defmodule RC do
def entropy(str) do
leng = String.length(str)
String.to_charlist(str)
|> Enum.reduce(Map.new, fn c,acc -> Map.update(acc, c, 1, &(&1+1)) end)
|> Map.values
|> Enum.reduce(0, fn count, entropy ->
freq = count / leng
entropy - freq * :math.log2(freq) # log2 was... |
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-... | #F.23 | F# | // include the code from /wiki/Entropy#F.23 for the entropy function
let fiboword =
Seq.unfold
(fun (state : string * string) ->
Some (fst state, (snd state, (snd state) + (fst state)))) ("1", "0")
printfn "%3s %10s %10s %s" "#" "Length" "Entropy" "Word (if length < 40)"
Seq.iteri (fun i... |
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
... | #Clojure | Clojure | (defn fasta [pathname]
(with-open [r (clojure.java.io/reader pathname)]
(doseq [line (line-seq r)]
(if (= (first line) \>)
(print (format "%n%s: " (subs line 1)))
(print line))))) |
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
... | #Common_Lisp | Common Lisp | ;; * The input file as a parameter
(defparameter *input* #p"fasta.txt"
"The input file name.")
;; * Reading the data
(with-open-file (data *input*)
(loop
:for line = (read-line data nil nil)
:while line
;; Check if we have a comment using a simple test instead of a RegEx
:if (char=... |
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... | #11l | 11l | F farey(n)
V a = 0
V b = 1
V c = 1
V d = n
V far = ‘0/1 ’
V farn = 1
L c <= n
V k = (n + b) I/ d
(a, b, c, d) = (c, d, k * c - a, k * d - b)
far ‘’= a‘/’b‘ ’
farn++
R (far, farn)
L(i) 1..11
print(i‘: ’farey(i)[0])
L(i) (100..1000).step(100)
print(i‘: ’farey(i)[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... | #11l | 11l | F _basechange_int(=num, b)
‘
Return list of ints representing positive num in base b
’
I num == 0
R [0]
[Int] result
L num != 0
(num, V d) = divmod(num, b)
result.append(d)
R reversed(result)
F fairshare(b, n)
[Int] r
L(i) 0..
r [+]= sum(_basechange_int(i, b)) % b
... |
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... | #C.2B.2B | C++ | #include <exception>
#include <iomanip>
#include <iostream>
#include <numeric>
#include <sstream>
#include <vector>
class Frac {
public:
Frac() : num(0), denom(1) {}
Frac(int n, int d) {
if (d == 0) {
throw std::runtime_error("d must not be zero");
}
int sign_of_d = d < 0 ? -1 : 1;
int g = std::gcd... |
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... | #EchoLisp | EchoLisp |
(lib 'math) ;; for bernoulli numbers
(string-delimiter "")
;; returns list of polynomial coefficients
(define (Faulhaber p)
(cons 0
(for/list ([k (in-range p -1 -1)])
(* (Cnp (1+ p) k) (bernoulli k)))))
;; prints formal polynomial
(define (task (pmax 10))
(for ((p pmax))
(writeln p '→ (/ 1 (1+ p)) '... |
http://rosettacode.org/wiki/Fermat_numbers | Fermat numbers | In mathematics, a Fermat number, named after Pierre de Fermat who first studied them, is a positive integer of the form Fn = 22n + 1 where n is a non-negative integer.
Despite the simplicity of generating Fermat numbers, they have some powerful mathematical properties and are extensively used in cryptography & pseudo-... | #Phix | Phix | with javascript_semantics
-- demo\rosetta\Fermat.exw
include mpfr.e
procedure fermat(mpz res, integer n)
integer pn = power(2,n)
mpz_ui_pow_ui(res,2,pn)
mpz_add_si(res,res,1)
end procedure
mpz fn = mpz_init()
constant lim = iff(platform()=JS?18:29), -- (see note)
print_lim = iff(platform()=JS?1... |
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}}
... | #AWK | AWK |
function sequence(values, howmany) {
init_length = length(values)
for (i=init_length + 1; i<=howmany; i++) {
values[i] = 0
for (j=1; j<=init_length; j++) {
values[i] += values[i-j]
}
}
result = ""
for (i in values) {
result = result values[i] " "
}
... |
http://rosettacode.org/wiki/Feigenbaum_constant_calculation | Feigenbaum constant calculation | Task
Calculate the Feigenbaum constant.
See
Details in the Wikipedia article: Feigenbaum constant.
| #Modula-2 | Modula-2 | MODULE Feigenbaum;
FROM FormatString IMPORT FormatString;
FROM LongStr IMPORT RealToStr;
FROM Terminal IMPORT WriteString,WriteLn,ReadChar;
VAR
buf : ARRAY[0..63] OF CHAR;
i,j,k,max_it,max_it_j : INTEGER;
a,x,y,d,a1,a2,d1 : LONGREAL;
BEGIN
max_it := 13;
max_it_j := 10;
a1 := 1.0;
a2 := 0... |
http://rosettacode.org/wiki/Feigenbaum_constant_calculation | Feigenbaum constant calculation | Task
Calculate the Feigenbaum constant.
See
Details in the Wikipedia article: Feigenbaum constant.
| #Nim | Nim | import strformat
iterator feigenbaum(): tuple[n: int; δ: float] =
## Yield successive approximations of Feigenbaum constant.
const
MaxI = 13
MaxJ = 10
var
a1 = 1.0
a2 = 0.0
δ = 3.2
for i in 2..MaxI:
var a = a1 + (a1 - a2) / δ
for j in 1..MaxJ:
var x, y = 0.0
for _ i... |
http://rosettacode.org/wiki/File_extension_is_in_extensions_list | File extension is in extensions list | File extension is in extensions list
You are encouraged to solve this task according to the task description, using any language you may know.
Filename extensions are a rudimentary but commonly used way of identifying files types.
Task
Given an arbitrary filename and a list of extensions, tell whether the filename... | #Raku | Raku | sub check-extension ($filename, *@extensions) {
so $filename ~~ /:i '.' @extensions $/
}
# Testing:
my @extensions = <zip rar 7z gz archive A## tar.bz2>;
my @files= <
MyData.a## MyData.tar.Gz MyData.gzip MyData.7z.backup MyData... MyData
MyData_v1.0.tar.bz2 MyData_v1.0.bz2
>;
say "{$_.fmt: '%-19s'... |
http://rosettacode.org/wiki/File_extension_is_in_extensions_list | File extension is in extensions list | File extension is in extensions list
You are encouraged to solve this task according to the task description, using any language you may know.
Filename extensions are a rudimentary but commonly used way of identifying files types.
Task
Given an arbitrary filename and a list of extensions, tell whether the filename... | #REXX | REXX | /*REXX pgm displays if a filename has a known extension (as per a list of extensions). */
$= 'zip rar 7z gz archive A## tar.bz2'; upper $ /*a list of "allowable" file extensions*/
parse arg fn /*obtain optional argument from the CL.*/
@.= ... |
http://rosettacode.org/wiki/File_modification_time | File modification time | Task
Get and set the modification time of a file.
| #PHP | PHP | <?php
$filename = 'input.txt';
$mtime = filemtime($filename); // seconds since the epoch
touch($filename,
time(), // set mtime to current time
fileatime($filename)); // keep atime unchanged
?> |
http://rosettacode.org/wiki/File_modification_time | File modification time | Task
Get and set the modification time of a file.
| #PicoLisp | PicoLisp | (let File "test.file"
(and
(info File)
(prinl (stamp (cadr @) (cddr @))) ) # Print date and time in UTC
(call 'touch File) ) # Set modification time to "now" |
http://rosettacode.org/wiki/File_modification_time | File modification time | Task
Get and set the modification time of a file.
| #Pop11 | Pop11 | ;;; Print modification time (seconds since Epoch)
sysmodtime('file') => |
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.