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http://rosettacode.org/wiki/Delete_a_file
Delete a file
Task Delete a file called "input.txt" and delete a directory called "docs". This should be done twice: once "here", i.e. in the current working directory and once in the filesystem root.
#Objective-C
Objective-C
NSFileManager *fm = [NSFileManager defaultManager];   // Pre-OS X 10.5 [fm removeFileAtPath:@"input.txt" handler:nil]; [fm removeFileAtPath:@"/input.txt" handler:nil]; [fm removeFileAtPath:@"docs" handler:nil]; [fm removeFileAtPath:@"/docs" handler:nil];   // OS X 10.5+ [fm removeItemAtPath:@"input.txt" error:NULL]; [fm removeItemAtPath:@"/input.txt" error:NULL]; [fm removeItemAtPath:@"docs" error:NULL]; [fm removeItemAtPath:@"/docs" error:NULL];
http://rosettacode.org/wiki/Detect_division_by_zero
Detect division by zero
Task Write a function to detect a   divide by zero error   without checking if the denominator is zero.
#Perl
Perl
sub div_check {local $@; eval {$_[0] / $_[1]}; $@ and $@ =~ /division by zero/;}
http://rosettacode.org/wiki/Detect_division_by_zero
Detect division by zero
Task Write a function to detect a   divide by zero error   without checking if the denominator is zero.
#Phix
Phix
try integer i = 1/0 catch e ?e[E_USER] end try puts(1,"still running...\n")
http://rosettacode.org/wiki/Determine_if_a_string_is_numeric
Determine if a string is numeric
Task Create a boolean function which takes in a string and tells whether it is a numeric string (floating point and negative numbers included) in the syntax the language uses for numeric literals or numbers converted from strings. Other tasks related to string operations: Metrics Array length String length Copy a string Empty string  (assignment) Counting Word frequency Letter frequency Jewels and stones I before E except after C Bioinformatics/base count Count occurrences of a substring Count how many vowels and consonants occur in a string Remove/replace XXXX redacted Conjugate a Latin verb Remove vowels from a string String interpolation (included) Strip block comments Strip comments from a string Strip a set of characters from a string Strip whitespace from a string -- top and tail Strip control codes and extended characters from a string Anagrams/Derangements/shuffling Word wheel ABC problem Sattolo cycle Knuth shuffle Ordered words Superpermutation minimisation Textonyms (using a phone text pad) Anagrams Anagrams/Deranged anagrams Permutations/Derangements Find/Search/Determine ABC words Odd words Word ladder Semordnilap Word search Wordiff  (game) String matching Tea cup rim text Alternade words Changeable words State name puzzle String comparison Unique characters Unique characters in each string Extract file extension Levenshtein distance Palindrome detection Common list elements Longest common suffix Longest common prefix Compare a list of strings Longest common substring Find common directory path Words from neighbour ones Change e letters to i in words Non-continuous subsequences Longest common subsequence Longest palindromic substrings Longest increasing subsequence Words containing "the" substring Sum of the digits of n is substring of n Determine if a string is numeric Determine if a string is collapsible Determine if a string is squeezable Determine if a string has all unique characters Determine if a string has all the same characters Longest substrings without repeating characters Find words which contains all the vowels Find words which contains most consonants Find words which contains more than 3 vowels Find words which first and last three letters are equals Find words which odd letters are consonants and even letters are vowels or vice_versa Formatting Substring Rep-string Word wrap String case Align columns Literals/String Repeat a string Brace expansion Brace expansion using ranges Reverse a string Phrase reversals Comma quibbling Special characters String concatenation Substring/Top and tail Commatizing numbers Reverse words in a string Suffixation of decimal numbers Long literals, with continuations Numerical and alphabetical suffixes Abbreviations, easy Abbreviations, simple Abbreviations, automatic Song lyrics/poems/Mad Libs/phrases Mad Libs Magic 8-ball 99 Bottles of Beer The Name Game (a song) The Old lady swallowed a fly The Twelve Days of Christmas Tokenize Text between Tokenize a string Word break problem Tokenize a string with escaping Split a character string based on change of character Sequences Show ASCII table De Bruijn sequences Self-referential sequences Generate lower case ASCII alphabet
#Maple
Maple
isNumeric := proc(s) try if type(parse(s), numeric) then printf("The string is numeric."): else printf("The string is not numeric."): end if: catch: printf("The string is not numeric."): end try: end proc:
http://rosettacode.org/wiki/Determine_if_a_string_is_numeric
Determine if a string is numeric
Task Create a boolean function which takes in a string and tells whether it is a numeric string (floating point and negative numbers included) in the syntax the language uses for numeric literals or numbers converted from strings. Other tasks related to string operations: Metrics Array length String length Copy a string Empty string  (assignment) Counting Word frequency Letter frequency Jewels and stones I before E except after C Bioinformatics/base count Count occurrences of a substring Count how many vowels and consonants occur in a string Remove/replace XXXX redacted Conjugate a Latin verb Remove vowels from a string String interpolation (included) Strip block comments Strip comments from a string Strip a set of characters from a string Strip whitespace from a string -- top and tail Strip control codes and extended characters from a string Anagrams/Derangements/shuffling Word wheel ABC problem Sattolo cycle Knuth shuffle Ordered words Superpermutation minimisation Textonyms (using a phone text pad) Anagrams Anagrams/Deranged anagrams Permutations/Derangements Find/Search/Determine ABC words Odd words Word ladder Semordnilap Word search Wordiff  (game) String matching Tea cup rim text Alternade words Changeable words State name puzzle String comparison Unique characters Unique characters in each string Extract file extension Levenshtein distance Palindrome detection Common list elements Longest common suffix Longest common prefix Compare a list of strings Longest common substring Find common directory path Words from neighbour ones Change e letters to i in words Non-continuous subsequences Longest common subsequence Longest palindromic substrings Longest increasing subsequence Words containing "the" substring Sum of the digits of n is substring of n Determine if a string is numeric Determine if a string is collapsible Determine if a string is squeezable Determine if a string has all unique characters Determine if a string has all the same characters Longest substrings without repeating characters Find words which contains all the vowels Find words which contains most consonants Find words which contains more than 3 vowels Find words which first and last three letters are equals Find words which odd letters are consonants and even letters are vowels or vice_versa Formatting Substring Rep-string Word wrap String case Align columns Literals/String Repeat a string Brace expansion Brace expansion using ranges Reverse a string Phrase reversals Comma quibbling Special characters String concatenation Substring/Top and tail Commatizing numbers Reverse words in a string Suffixation of decimal numbers Long literals, with continuations Numerical and alphabetical suffixes Abbreviations, easy Abbreviations, simple Abbreviations, automatic Song lyrics/poems/Mad Libs/phrases Mad Libs Magic 8-ball 99 Bottles of Beer The Name Game (a song) The Old lady swallowed a fly The Twelve Days of Christmas Tokenize Text between Tokenize a string Word break problem Tokenize a string with escaping Split a character string based on change of character Sequences Show ASCII table De Bruijn sequences Self-referential sequences Generate lower case ASCII alphabet
#Mathematica_.2F_Wolfram_Language
Mathematica / Wolfram Language
NumberQ[ToExpression["02553352000242"]]
http://rosettacode.org/wiki/Determine_if_a_string_has_all_unique_characters
Determine if a string has all unique characters
Task Given a character string   (which may be empty, or have a length of zero characters):   create a function/procedure/routine to:   determine if all the characters in the string are unique   indicate if or which character is duplicated and where   display each string and its length   (as the strings are being examined)   a zero─length (empty) string shall be considered as unique   process the strings from left─to─right   if       unique,   display a message saying such   if not unique,   then:   display a message saying such   display what character is duplicated   only the 1st non─unique character need be displayed   display where "both" duplicated characters are in the string   the above messages can be part of a single message   display the hexadecimal value of the duplicated character Use (at least) these five test values   (strings):   a string of length     0   (an empty string)   a string of length     1   which is a single period   (.)   a string of length     6   which contains:   abcABC   a string of length     7   which contains a blank in the middle:   XYZ  ZYX   a string of length   36   which   doesn't   contain the letter "oh": 1234567890ABCDEFGHIJKLMN0PQRSTUVWXYZ Show all output here on this page. Other tasks related to string operations: Metrics Array length String length Copy a string Empty string  (assignment) Counting Word frequency Letter frequency Jewels and stones I before E except after C Bioinformatics/base count Count occurrences of a substring Count how many vowels and consonants occur in a string Remove/replace XXXX redacted Conjugate a Latin verb Remove vowels from a string String interpolation (included) Strip block comments Strip comments from a string Strip a set of characters from a string Strip whitespace from a string -- top and tail Strip control codes and extended characters from a string Anagrams/Derangements/shuffling Word wheel ABC problem Sattolo cycle Knuth shuffle Ordered words Superpermutation minimisation Textonyms (using a phone text pad) Anagrams Anagrams/Deranged anagrams Permutations/Derangements Find/Search/Determine ABC words Odd words Word ladder Semordnilap Word search Wordiff  (game) String matching Tea cup rim text Alternade words Changeable words State name puzzle String comparison Unique characters Unique characters in each string Extract file extension Levenshtein distance Palindrome detection Common list elements Longest common suffix Longest common prefix Compare a list of strings Longest common substring Find common directory path Words from neighbour ones Change e letters to i in words Non-continuous subsequences Longest common subsequence Longest palindromic substrings Longest increasing subsequence Words containing "the" substring Sum of the digits of n is substring of n Determine if a string is numeric Determine if a string is collapsible Determine if a string is squeezable Determine if a string has all unique characters Determine if a string has all the same characters Longest substrings without repeating characters Find words which contains all the vowels Find words which contains most consonants Find words which contains more than 3 vowels Find words which first and last three letters are equals Find words which odd letters are consonants and even letters are vowels or vice_versa Formatting Substring Rep-string Word wrap String case Align columns Literals/String Repeat a string Brace expansion Brace expansion using ranges Reverse a string Phrase reversals Comma quibbling Special characters String concatenation Substring/Top and tail Commatizing numbers Reverse words in a string Suffixation of decimal numbers Long literals, with continuations Numerical and alphabetical suffixes Abbreviations, easy Abbreviations, simple Abbreviations, automatic Song lyrics/poems/Mad Libs/phrases Mad Libs Magic 8-ball 99 Bottles of Beer The Name Game (a song) The Old lady swallowed a fly The Twelve Days of Christmas Tokenize Text between Tokenize a string Word break problem Tokenize a string with escaping Split a character string based on change of character Sequences Show ASCII table De Bruijn sequences Self-referential sequences Generate lower case ASCII alphabet
#zkl
zkl
fcn stringUniqueness(str){ // Does not handle Unicode sz,unique,uz,counts := str.len(), str.unique(), unique.len(), str.counts(); println("Length %d: \"%s\"".fmt(sz,str)); if(sz==uz or uz==1) println("\tAll characters are unique"); else // counts is (char,count, char,count, ...) println("\tDuplicate: ", counts.pump(List,Void.Read,fcn(str,c,n){ if(n>1){ is,z:=List(),-1; do(n){ is.append(z=str.find(c,z+1)) } "'%s' (0x%x)[%s]".fmt(c,c.toAsc(),is.concat(",")) } else Void.Skip }.fp(str)).concat(", ")); }
http://rosettacode.org/wiki/Digital_root
Digital root
The digital root, X {\displaystyle X} , of a number, n {\displaystyle n} , is calculated: find X {\displaystyle X} as the sum of the digits of n {\displaystyle n} find a new X {\displaystyle X} by summing the digits of X {\displaystyle X} , repeating until X {\displaystyle X} has only one digit. The additive persistence is the number of summations required to obtain the single digit. The task is to calculate the additive persistence and the digital root of a number, e.g.: 627615 {\displaystyle 627615} has additive persistence 2 {\displaystyle 2} and digital root of 9 {\displaystyle 9} ; 39390 {\displaystyle 39390} has additive persistence 2 {\displaystyle 2} and digital root of 6 {\displaystyle 6} ; 588225 {\displaystyle 588225} has additive persistence 2 {\displaystyle 2} and digital root of 3 {\displaystyle 3} ; 393900588225 {\displaystyle 393900588225} has additive persistence 2 {\displaystyle 2} and digital root of 9 {\displaystyle 9} ; The digital root may be calculated in bases other than 10. See Casting out nines for this wiki's use of this procedure. Digital root/Multiplicative digital root Sum digits of an integer Digital root sequence on OEIS Additive persistence sequence on OEIS Iterated digits squaring
#Scheme
Scheme
; Convert an integer into a list of its digits.   (define integer->list (lambda (integer) (let loop ((list '()) (int integer)) (if (< int 10) (cons int list) (loop (cons (remainder int 10) list) (quotient int 10))))))   ; Return the sum of the digits of an integer.   (define integer-sum-digits (lambda (integer) (fold-left + 0 (integer->list integer))))   ; Compute the digital root (additive) and additive persistence of an integer. ; Return as a cons of (adr . ap).   (define adr-ap (lambda (integer) (let loop ((int integer) (cnt 0)) (if (< int 10) (cons int cnt) (loop (integer-sum-digits int) (1+ cnt))))))   ; Emit a table of integer, digital root (additive), and additive persistence ; for the example integers given.   (printf "~13@a ~6@a ~6@a~%" "Integer" "Root" "Pers.") (let rowloop ((intlist '(627615 39390 588225 393900588225 0 1 68010887038))) (when (pair? intlist) (let* ((int (car intlist)) (aa (adr-ap int))) (printf "~13@a ~6@a ~6@a~%" int (car aa) (cdr aa)) (rowloop (cdr intlist)))))
http://rosettacode.org/wiki/Dot_product
Dot product
Task Create a function/use an in-built function, to compute the   dot product,   also known as the   scalar product   of two vectors. If possible, make the vectors of arbitrary length. As an example, compute the dot product of the vectors:   [1,  3, -5]     and   [4, -2, -1] If implementing the dot product of two vectors directly:   each vector must be the same length   multiply corresponding terms from each vector   sum the products   (to produce the answer) Related task   Vector products
#PARI.2FGP
PARI/GP
dot(u,v)={ sum(i=1,#u,u[i]*v[i]) };
http://rosettacode.org/wiki/Department_numbers
Department numbers
There is a highly organized city that has decided to assign a number to each of their departments:   police department   sanitation department   fire department Each department can have a number between   1   and   7   (inclusive). The three department numbers are to be unique (different from each other) and must add up to   12. The Chief of the Police doesn't like odd numbers and wants to have an even number for his department. Task Write a computer program which outputs all valid combinations. Possible output   (for the 1st and 14th solutions): --police-- --sanitation-- --fire-- 2 3 7 6 5 1
#JavaScript
JavaScript
(function () { 'use strict';   // concatMap :: (a -> [b]) -> [a] -> [b] function concatMap(f, xs) { return [].concat.apply([], xs.map(f)); };   return '(Police, Sanitation, Fire)\n' + concatMap(function (x) { return concatMap(function (y) { return concatMap(function (z) { return z !== y && 1 <= z && z <= 7 ? [ [x, y, z] ] : []; }, [12 - (x + y)]); }, [1, 2, 3, 4, 5, 6, 7]); }, [2, 4, 6]) .map(JSON.stringify) .join('\n'); })();
http://rosettacode.org/wiki/Delete_a_file
Delete a file
Task Delete a file called "input.txt" and delete a directory called "docs". This should be done twice: once "here", i.e. in the current working directory and once in the filesystem root.
#OCaml
OCaml
Sys.remove "input.txt";; Sys.remove "/input.txt";;
http://rosettacode.org/wiki/Delete_a_file
Delete a file
Task Delete a file called "input.txt" and delete a directory called "docs". This should be done twice: once "here", i.e. in the current working directory and once in the filesystem root.
#ooRexx
ooRexx
/*REXX pgm deletes a file */ file= 'afile.txt' /*name of a file to be deleted.*/ res=sysFileDelete(file); Say file 'res='res File= 'bfile.txt' /*name of a file to be deleted.*/ res=sysFileDelete(file); Say file 'res='res
http://rosettacode.org/wiki/Detect_division_by_zero
Detect division by zero
Task Write a function to detect a   divide by zero error   without checking if the denominator is zero.
#PHP
PHP
function div_check($x, $y) { @trigger_error(''); // a dummy to detect when error didn't occur @($x / $y); $e = error_get_last(); return $e['message'] != ''; }
http://rosettacode.org/wiki/Detect_division_by_zero
Detect division by zero
Task Write a function to detect a   divide by zero error   without checking if the denominator is zero.
#PicoLisp
PicoLisp
(catch '("Div/0") (/ A B))
http://rosettacode.org/wiki/Detect_division_by_zero
Detect division by zero
Task Write a function to detect a   divide by zero error   without checking if the denominator is zero.
#PL.2FI
PL/I
Proc DivideDZ(a,b) Returns(Float Bin(33)); Dcl (a,b,c) Float Bin(33); On ZeroDivide GoTo MyError; c=a/b; Return(c); MyError: Put Skip List('Divide by Zero Detected!'); End DivideDZ;   xx=DivideDZ(1,0);
http://rosettacode.org/wiki/Determine_if_a_string_is_numeric
Determine if a string is numeric
Task Create a boolean function which takes in a string and tells whether it is a numeric string (floating point and negative numbers included) in the syntax the language uses for numeric literals or numbers converted from strings. Other tasks related to string operations: Metrics Array length String length Copy a string Empty string  (assignment) Counting Word frequency Letter frequency Jewels and stones I before E except after C Bioinformatics/base count Count occurrences of a substring Count how many vowels and consonants occur in a string Remove/replace XXXX redacted Conjugate a Latin verb Remove vowels from a string String interpolation (included) Strip block comments Strip comments from a string Strip a set of characters from a string Strip whitespace from a string -- top and tail Strip control codes and extended characters from a string Anagrams/Derangements/shuffling Word wheel ABC problem Sattolo cycle Knuth shuffle Ordered words Superpermutation minimisation Textonyms (using a phone text pad) Anagrams Anagrams/Deranged anagrams Permutations/Derangements Find/Search/Determine ABC words Odd words Word ladder Semordnilap Word search Wordiff  (game) String matching Tea cup rim text Alternade words Changeable words State name puzzle String comparison Unique characters Unique characters in each string Extract file extension Levenshtein distance Palindrome detection Common list elements Longest common suffix Longest common prefix Compare a list of strings Longest common substring Find common directory path Words from neighbour ones Change e letters to i in words Non-continuous subsequences Longest common subsequence Longest palindromic substrings Longest increasing subsequence Words containing "the" substring Sum of the digits of n is substring of n Determine if a string is numeric Determine if a string is collapsible Determine if a string is squeezable Determine if a string has all unique characters Determine if a string has all the same characters Longest substrings without repeating characters Find words which contains all the vowels Find words which contains most consonants Find words which contains more than 3 vowels Find words which first and last three letters are equals Find words which odd letters are consonants and even letters are vowels or vice_versa Formatting Substring Rep-string Word wrap String case Align columns Literals/String Repeat a string Brace expansion Brace expansion using ranges Reverse a string Phrase reversals Comma quibbling Special characters String concatenation Substring/Top and tail Commatizing numbers Reverse words in a string Suffixation of decimal numbers Long literals, with continuations Numerical and alphabetical suffixes Abbreviations, easy Abbreviations, simple Abbreviations, automatic Song lyrics/poems/Mad Libs/phrases Mad Libs Magic 8-ball 99 Bottles of Beer The Name Game (a song) The Old lady swallowed a fly The Twelve Days of Christmas Tokenize Text between Tokenize a string Word break problem Tokenize a string with escaping Split a character string based on change of character Sequences Show ASCII table De Bruijn sequences Self-referential sequences Generate lower case ASCII alphabet
#MATLAB
MATLAB
  function r = isnum(a) r = ~isnan(str2double(a)) end   % tests disp(isnum(123)) % 1 disp(isnum("123")) % 1 disp(isnum("foo123")) % 0 disp(isnum("123bar")) % 0 disp(isnum("3.1415")) % 1    
http://rosettacode.org/wiki/Determine_if_a_string_is_numeric
Determine if a string is numeric
Task Create a boolean function which takes in a string and tells whether it is a numeric string (floating point and negative numbers included) in the syntax the language uses for numeric literals or numbers converted from strings. Other tasks related to string operations: Metrics Array length String length Copy a string Empty string  (assignment) Counting Word frequency Letter frequency Jewels and stones I before E except after C Bioinformatics/base count Count occurrences of a substring Count how many vowels and consonants occur in a string Remove/replace XXXX redacted Conjugate a Latin verb Remove vowels from a string String interpolation (included) Strip block comments Strip comments from a string Strip a set of characters from a string Strip whitespace from a string -- top and tail Strip control codes and extended characters from a string Anagrams/Derangements/shuffling Word wheel ABC problem Sattolo cycle Knuth shuffle Ordered words Superpermutation minimisation Textonyms (using a phone text pad) Anagrams Anagrams/Deranged anagrams Permutations/Derangements Find/Search/Determine ABC words Odd words Word ladder Semordnilap Word search Wordiff  (game) String matching Tea cup rim text Alternade words Changeable words State name puzzle String comparison Unique characters Unique characters in each string Extract file extension Levenshtein distance Palindrome detection Common list elements Longest common suffix Longest common prefix Compare a list of strings Longest common substring Find common directory path Words from neighbour ones Change e letters to i in words Non-continuous subsequences Longest common subsequence Longest palindromic substrings Longest increasing subsequence Words containing "the" substring Sum of the digits of n is substring of n Determine if a string is numeric Determine if a string is collapsible Determine if a string is squeezable Determine if a string has all unique characters Determine if a string has all the same characters Longest substrings without repeating characters Find words which contains all the vowels Find words which contains most consonants Find words which contains more than 3 vowels Find words which first and last three letters are equals Find words which odd letters are consonants and even letters are vowels or vice_versa Formatting Substring Rep-string Word wrap String case Align columns Literals/String Repeat a string Brace expansion Brace expansion using ranges Reverse a string Phrase reversals Comma quibbling Special characters String concatenation Substring/Top and tail Commatizing numbers Reverse words in a string Suffixation of decimal numbers Long literals, with continuations Numerical and alphabetical suffixes Abbreviations, easy Abbreviations, simple Abbreviations, automatic Song lyrics/poems/Mad Libs/phrases Mad Libs Magic 8-ball 99 Bottles of Beer The Name Game (a song) The Old lady swallowed a fly The Twelve Days of Christmas Tokenize Text between Tokenize a string Word break problem Tokenize a string with escaping Split a character string based on change of character Sequences Show ASCII table De Bruijn sequences Self-referential sequences Generate lower case ASCII alphabet
#Maxima
Maxima
numberp(parse_string("170141183460469231731687303715884105727"));
http://rosettacode.org/wiki/Digital_root
Digital root
The digital root, X {\displaystyle X} , of a number, n {\displaystyle n} , is calculated: find X {\displaystyle X} as the sum of the digits of n {\displaystyle n} find a new X {\displaystyle X} by summing the digits of X {\displaystyle X} , repeating until X {\displaystyle X} has only one digit. The additive persistence is the number of summations required to obtain the single digit. The task is to calculate the additive persistence and the digital root of a number, e.g.: 627615 {\displaystyle 627615} has additive persistence 2 {\displaystyle 2} and digital root of 9 {\displaystyle 9} ; 39390 {\displaystyle 39390} has additive persistence 2 {\displaystyle 2} and digital root of 6 {\displaystyle 6} ; 588225 {\displaystyle 588225} has additive persistence 2 {\displaystyle 2} and digital root of 3 {\displaystyle 3} ; 393900588225 {\displaystyle 393900588225} has additive persistence 2 {\displaystyle 2} and digital root of 9 {\displaystyle 9} ; The digital root may be calculated in bases other than 10. See Casting out nines for this wiki's use of this procedure. Digital root/Multiplicative digital root Sum digits of an integer Digital root sequence on OEIS Additive persistence sequence on OEIS Iterated digits squaring
#Seed7
Seed7
$ include "seed7_05.s7i"; include "bigint.s7i";   const func bigInteger: digitalRoot (in var bigInteger: num, in bigInteger: base, inout bigInteger: persistence) is func result var bigInteger: sum is 0_; begin persistence := 0_; while num >= base do sum := 0_; while num > 0_ do sum +:= num rem base; num := num div base; end while; num := sum; incr(persistence); end while; end func;   const proc: main is func local var bigInteger: num is 0_; var bigInteger: root is 0_; var bigInteger: persistence is 0_; begin for num range [] (627615_, 39390_, 588225_, 393900588225_) do root := digitalRoot(num, 10_, persistence); writeln(num <& " has additive persistence " <& persistence <& " and digital root of " <& root); end for; end func;
http://rosettacode.org/wiki/Digital_root
Digital root
The digital root, X {\displaystyle X} , of a number, n {\displaystyle n} , is calculated: find X {\displaystyle X} as the sum of the digits of n {\displaystyle n} find a new X {\displaystyle X} by summing the digits of X {\displaystyle X} , repeating until X {\displaystyle X} has only one digit. The additive persistence is the number of summations required to obtain the single digit. The task is to calculate the additive persistence and the digital root of a number, e.g.: 627615 {\displaystyle 627615} has additive persistence 2 {\displaystyle 2} and digital root of 9 {\displaystyle 9} ; 39390 {\displaystyle 39390} has additive persistence 2 {\displaystyle 2} and digital root of 6 {\displaystyle 6} ; 588225 {\displaystyle 588225} has additive persistence 2 {\displaystyle 2} and digital root of 3 {\displaystyle 3} ; 393900588225 {\displaystyle 393900588225} has additive persistence 2 {\displaystyle 2} and digital root of 9 {\displaystyle 9} ; The digital root may be calculated in bases other than 10. See Casting out nines for this wiki's use of this procedure. Digital root/Multiplicative digital root Sum digits of an integer Digital root sequence on OEIS Additive persistence sequence on OEIS Iterated digits squaring
#Sidef
Sidef
func digroot (r, base = 10) { var root = r.base(base) var persistence = 0 while (root.len > 1) { root = root.chars.map{|n| Number(n, 36) }.sum(0).base(base) ++persistence } return(persistence, root) }   var nums = [5, 627615, 39390, 588225, 393900588225] var bases = [2, 3, 8, 10, 16, 36] var fmt = "%25s(%2s): persistance = %s, root = %2s\n"   nums << (550777011503 * 105564897893993412813307040538786690718089963180462913406682192479)   bases.each { |b| nums.each { |n| var x = n.base(b) x = 'BIG' if (x.len > 25) fmt.printf(x, b, digroot(n, b)) } print "\n" }
http://rosettacode.org/wiki/Dot_product
Dot product
Task Create a function/use an in-built function, to compute the   dot product,   also known as the   scalar product   of two vectors. If possible, make the vectors of arbitrary length. As an example, compute the dot product of the vectors:   [1,  3, -5]     and   [4, -2, -1] If implementing the dot product of two vectors directly:   each vector must be the same length   multiply corresponding terms from each vector   sum the products   (to produce the answer) Related task   Vector products
#Pascal
Pascal
sub dotprod { my($vec_a, $vec_b) = @_; die "they must have the same size\n" unless @$vec_a == @$vec_b; my $sum = 0; $sum += $vec_a->[$_] * $vec_b->[$_] for 0..$#$vec_a; return $sum; }   my @vec_a = (1,3,-5); my @vec_b = (4,-2,-1);   print dotprod(\@vec_a,\@vec_b), "\n"; # 3
http://rosettacode.org/wiki/Department_numbers
Department numbers
There is a highly organized city that has decided to assign a number to each of their departments:   police department   sanitation department   fire department Each department can have a number between   1   and   7   (inclusive). The three department numbers are to be unique (different from each other) and must add up to   12. The Chief of the Police doesn't like odd numbers and wants to have an even number for his department. Task Write a computer program which outputs all valid combinations. Possible output   (for the 1st and 14th solutions): --police-- --sanitation-- --fire-- 2 3 7 6 5 1
#jq
jq
{"fire":1,"police":4,"sanitation":7}
http://rosettacode.org/wiki/Department_numbers
Department numbers
There is a highly organized city that has decided to assign a number to each of their departments:   police department   sanitation department   fire department Each department can have a number between   1   and   7   (inclusive). The three department numbers are to be unique (different from each other) and must add up to   12. The Chief of the Police doesn't like odd numbers and wants to have an even number for his department. Task Write a computer program which outputs all valid combinations. Possible output   (for the 1st and 14th solutions): --police-- --sanitation-- --fire-- 2 3 7 6 5 1
#Julia
Julia
using Printf   function findsolution(rng=1:7) rst = Matrix{Int}(0, 3) for p in rng, f in rng, s in rng if p != s != f != p && p + s + f == 12 && iseven(p) rst = [rst; p s f] end end return rst end   function printsolutions(sol::Matrix{Int}) println(" Pol. Fire San.") println(" ---- ---- ----") for row in 1:size(sol, 1) @printf("%2i | %4i%7i%7i\n", row, sol[row, :]...) end end   printsolutions(findsolution())  
http://rosettacode.org/wiki/Delete_a_file
Delete a file
Task Delete a file called "input.txt" and delete a directory called "docs". This should be done twice: once "here", i.e. in the current working directory and once in the filesystem root.
#Oz
Oz
for Dir in ["/" "./"] do try {OS.unlink Dir#"output.txt"} catch _ then {System.showInfo "File does not exist."} end try {OS.rmDir Dir#"docs"} catch _ then {System.showInfo "Directory does not exist."} end end
http://rosettacode.org/wiki/Delete_a_file
Delete a file
Task Delete a file called "input.txt" and delete a directory called "docs". This should be done twice: once "here", i.e. in the current working directory and once in the filesystem root.
#PARI.2FGP
PARI/GP
system("rm -rf docs"); system("rm input.txt"); system("rm -rf /docs"); system("rm /input.txt");
http://rosettacode.org/wiki/Detect_division_by_zero
Detect division by zero
Task Write a function to detect a   divide by zero error   without checking if the denominator is zero.
#PL.2FSQL
PL/SQL
FUNCTION divide(n1 IN NUMBER, n2 IN NUMBER) RETURN BOOLEAN IS result NUMBER; BEGIN result := n1/n2; RETURN(FALSE); EXCEPTION WHEN ZERO_DIVIDE THEN RETURN(TRUE); END divide;
http://rosettacode.org/wiki/Detect_division_by_zero
Detect division by zero
Task Write a function to detect a   divide by zero error   without checking if the denominator is zero.
#PowerShell
PowerShell
  function div ($a, $b) { try{$a/$b} catch{"Bad parameters: `$a = $a and `$b = $b"} } div 10 2 div 1 0  
http://rosettacode.org/wiki/Determine_if_a_string_is_numeric
Determine if a string is numeric
Task Create a boolean function which takes in a string and tells whether it is a numeric string (floating point and negative numbers included) in the syntax the language uses for numeric literals or numbers converted from strings. Other tasks related to string operations: Metrics Array length String length Copy a string Empty string  (assignment) Counting Word frequency Letter frequency Jewels and stones I before E except after C Bioinformatics/base count Count occurrences of a substring Count how many vowels and consonants occur in a string Remove/replace XXXX redacted Conjugate a Latin verb Remove vowels from a string String interpolation (included) Strip block comments Strip comments from a string Strip a set of characters from a string Strip whitespace from a string -- top and tail Strip control codes and extended characters from a string Anagrams/Derangements/shuffling Word wheel ABC problem Sattolo cycle Knuth shuffle Ordered words Superpermutation minimisation Textonyms (using a phone text pad) Anagrams Anagrams/Deranged anagrams Permutations/Derangements Find/Search/Determine ABC words Odd words Word ladder Semordnilap Word search Wordiff  (game) String matching Tea cup rim text Alternade words Changeable words State name puzzle String comparison Unique characters Unique characters in each string Extract file extension Levenshtein distance Palindrome detection Common list elements Longest common suffix Longest common prefix Compare a list of strings Longest common substring Find common directory path Words from neighbour ones Change e letters to i in words Non-continuous subsequences Longest common subsequence Longest palindromic substrings Longest increasing subsequence Words containing "the" substring Sum of the digits of n is substring of n Determine if a string is numeric Determine if a string is collapsible Determine if a string is squeezable Determine if a string has all unique characters Determine if a string has all the same characters Longest substrings without repeating characters Find words which contains all the vowels Find words which contains most consonants Find words which contains more than 3 vowels Find words which first and last three letters are equals Find words which odd letters are consonants and even letters are vowels or vice_versa Formatting Substring Rep-string Word wrap String case Align columns Literals/String Repeat a string Brace expansion Brace expansion using ranges Reverse a string Phrase reversals Comma quibbling Special characters String concatenation Substring/Top and tail Commatizing numbers Reverse words in a string Suffixation of decimal numbers Long literals, with continuations Numerical and alphabetical suffixes Abbreviations, easy Abbreviations, simple Abbreviations, automatic Song lyrics/poems/Mad Libs/phrases Mad Libs Magic 8-ball 99 Bottles of Beer The Name Game (a song) The Old lady swallowed a fly The Twelve Days of Christmas Tokenize Text between Tokenize a string Word break problem Tokenize a string with escaping Split a character string based on change of character Sequences Show ASCII table De Bruijn sequences Self-referential sequences Generate lower case ASCII alphabet
#MAXScript
MAXScript
fn isNumeric str = ( try ( (str as integer) != undefined ) catch(false) )   isNumeric "123"
http://rosettacode.org/wiki/Determine_if_a_string_is_numeric
Determine if a string is numeric
Task Create a boolean function which takes in a string and tells whether it is a numeric string (floating point and negative numbers included) in the syntax the language uses for numeric literals or numbers converted from strings. Other tasks related to string operations: Metrics Array length String length Copy a string Empty string  (assignment) Counting Word frequency Letter frequency Jewels and stones I before E except after C Bioinformatics/base count Count occurrences of a substring Count how many vowels and consonants occur in a string Remove/replace XXXX redacted Conjugate a Latin verb Remove vowels from a string String interpolation (included) Strip block comments Strip comments from a string Strip a set of characters from a string Strip whitespace from a string -- top and tail Strip control codes and extended characters from a string Anagrams/Derangements/shuffling Word wheel ABC problem Sattolo cycle Knuth shuffle Ordered words Superpermutation minimisation Textonyms (using a phone text pad) Anagrams Anagrams/Deranged anagrams Permutations/Derangements Find/Search/Determine ABC words Odd words Word ladder Semordnilap Word search Wordiff  (game) String matching Tea cup rim text Alternade words Changeable words State name puzzle String comparison Unique characters Unique characters in each string Extract file extension Levenshtein distance Palindrome detection Common list elements Longest common suffix Longest common prefix Compare a list of strings Longest common substring Find common directory path Words from neighbour ones Change e letters to i in words Non-continuous subsequences Longest common subsequence Longest palindromic substrings Longest increasing subsequence Words containing "the" substring Sum of the digits of n is substring of n Determine if a string is numeric Determine if a string is collapsible Determine if a string is squeezable Determine if a string has all unique characters Determine if a string has all the same characters Longest substrings without repeating characters Find words which contains all the vowels Find words which contains most consonants Find words which contains more than 3 vowels Find words which first and last three letters are equals Find words which odd letters are consonants and even letters are vowels or vice_versa Formatting Substring Rep-string Word wrap String case Align columns Literals/String Repeat a string Brace expansion Brace expansion using ranges Reverse a string Phrase reversals Comma quibbling Special characters String concatenation Substring/Top and tail Commatizing numbers Reverse words in a string Suffixation of decimal numbers Long literals, with continuations Numerical and alphabetical suffixes Abbreviations, easy Abbreviations, simple Abbreviations, automatic Song lyrics/poems/Mad Libs/phrases Mad Libs Magic 8-ball 99 Bottles of Beer The Name Game (a song) The Old lady swallowed a fly The Twelve Days of Christmas Tokenize Text between Tokenize a string Word break problem Tokenize a string with escaping Split a character string based on change of character Sequences Show ASCII table De Bruijn sequences Self-referential sequences Generate lower case ASCII alphabet
#min
min
( dup (((int integer?) (pop false)) try) dip ((float float?) (pop false)) try or ) :numeric?
http://rosettacode.org/wiki/Digital_root
Digital root
The digital root, X {\displaystyle X} , of a number, n {\displaystyle n} , is calculated: find X {\displaystyle X} as the sum of the digits of n {\displaystyle n} find a new X {\displaystyle X} by summing the digits of X {\displaystyle X} , repeating until X {\displaystyle X} has only one digit. The additive persistence is the number of summations required to obtain the single digit. The task is to calculate the additive persistence and the digital root of a number, e.g.: 627615 {\displaystyle 627615} has additive persistence 2 {\displaystyle 2} and digital root of 9 {\displaystyle 9} ; 39390 {\displaystyle 39390} has additive persistence 2 {\displaystyle 2} and digital root of 6 {\displaystyle 6} ; 588225 {\displaystyle 588225} has additive persistence 2 {\displaystyle 2} and digital root of 3 {\displaystyle 3} ; 393900588225 {\displaystyle 393900588225} has additive persistence 2 {\displaystyle 2} and digital root of 9 {\displaystyle 9} ; The digital root may be calculated in bases other than 10. See Casting out nines for this wiki's use of this procedure. Digital root/Multiplicative digital root Sum digits of an integer Digital root sequence on OEIS Additive persistence sequence on OEIS Iterated digits squaring
#Smalltalk
Smalltalk
digitalRoot := [:nr :arIn | r := (nr printString asArray collect:#digitValue) sum. r > 9 ifTrue:[ digitalRoot value:r value:arIn+1. ] ifFalse:[ { arIn+1 . r } ]. ].   #( 627615 39390 588225 393900588225 10 199 1999999999999999999999999999999999999999999999999999999999999999999999999999999999999 ) do:[:nr | Transcript showCR:'%1 has digitalRoot %3 and Additive Resistance %2' withArguments:{nr},(digitalRoot value:nr value:0) ]
http://rosettacode.org/wiki/Digital_root
Digital root
The digital root, X {\displaystyle X} , of a number, n {\displaystyle n} , is calculated: find X {\displaystyle X} as the sum of the digits of n {\displaystyle n} find a new X {\displaystyle X} by summing the digits of X {\displaystyle X} , repeating until X {\displaystyle X} has only one digit. The additive persistence is the number of summations required to obtain the single digit. The task is to calculate the additive persistence and the digital root of a number, e.g.: 627615 {\displaystyle 627615} has additive persistence 2 {\displaystyle 2} and digital root of 9 {\displaystyle 9} ; 39390 {\displaystyle 39390} has additive persistence 2 {\displaystyle 2} and digital root of 6 {\displaystyle 6} ; 588225 {\displaystyle 588225} has additive persistence 2 {\displaystyle 2} and digital root of 3 {\displaystyle 3} ; 393900588225 {\displaystyle 393900588225} has additive persistence 2 {\displaystyle 2} and digital root of 9 {\displaystyle 9} ; The digital root may be calculated in bases other than 10. See Casting out nines for this wiki's use of this procedure. Digital root/Multiplicative digital root Sum digits of an integer Digital root sequence on OEIS Additive persistence sequence on OEIS Iterated digits squaring
#SmileBASIC
SmileBASIC
DEF DIGITAL_ROOT N OUT DR,AP AP=0 DR=N WHILE DR>9 INC AP STRDR$=STR$(DR) NEWDR=0 FOR I=0 TO LEN(STRDR$)-1 INC NEWDR,VAL(MID$(STRDR$,I,1)) NEXT DR=NEWDR WEND END
http://rosettacode.org/wiki/Dot_product
Dot product
Task Create a function/use an in-built function, to compute the   dot product,   also known as the   scalar product   of two vectors. If possible, make the vectors of arbitrary length. As an example, compute the dot product of the vectors:   [1,  3, -5]     and   [4, -2, -1] If implementing the dot product of two vectors directly:   each vector must be the same length   multiply corresponding terms from each vector   sum the products   (to produce the answer) Related task   Vector products
#Perl
Perl
sub dotprod { my($vec_a, $vec_b) = @_; die "they must have the same size\n" unless @$vec_a == @$vec_b; my $sum = 0; $sum += $vec_a->[$_] * $vec_b->[$_] for 0..$#$vec_a; return $sum; }   my @vec_a = (1,3,-5); my @vec_b = (4,-2,-1);   print dotprod(\@vec_a,\@vec_b), "\n"; # 3
http://rosettacode.org/wiki/Department_numbers
Department numbers
There is a highly organized city that has decided to assign a number to each of their departments:   police department   sanitation department   fire department Each department can have a number between   1   and   7   (inclusive). The three department numbers are to be unique (different from each other) and must add up to   12. The Chief of the Police doesn't like odd numbers and wants to have an even number for his department. Task Write a computer program which outputs all valid combinations. Possible output   (for the 1st and 14th solutions): --police-- --sanitation-- --fire-- 2 3 7 6 5 1
#Kotlin
Kotlin
// version 1.1.2   fun main(args: Array<String>) { println("Police Sanitation Fire") println("------ ---------- ----") var count = 0 for (i in 2..6 step 2) { for (j in 1..7) { if (j == i) continue for (k in 1..7) { if (k == i || k == j) continue if (i + j + k != 12) continue println(" $i $j $k") count++ } } } println("\n$count valid combinations") }
http://rosettacode.org/wiki/Delete_a_file
Delete a file
Task Delete a file called "input.txt" and delete a directory called "docs". This should be done twice: once "here", i.e. in the current working directory and once in the filesystem root.
#Pascal
Pascal
use File::Spec::Functions qw(catfile rootdir); # here unlink 'input.txt'; rmdir 'docs'; # root dir unlink catfile rootdir, 'input.txt'; rmdir catfile rootdir, 'docs';
http://rosettacode.org/wiki/Delete_a_file
Delete a file
Task Delete a file called "input.txt" and delete a directory called "docs". This should be done twice: once "here", i.e. in the current working directory and once in the filesystem root.
#Perl
Perl
use File::Spec::Functions qw(catfile rootdir); # here unlink 'input.txt'; rmdir 'docs'; # root dir unlink catfile rootdir, 'input.txt'; rmdir catfile rootdir, 'docs';
http://rosettacode.org/wiki/Detect_division_by_zero
Detect division by zero
Task Write a function to detect a   divide by zero error   without checking if the denominator is zero.
#Prolog
Prolog
  div(A, B, C, Ex) :- catch((C is A/B), Ex, (C = infinity)).  
http://rosettacode.org/wiki/Detect_division_by_zero
Detect division by zero
Task Write a function to detect a   divide by zero error   without checking if the denominator is zero.
#Pure
Pure
> 1/0, -1/0, 0/0; inf,-inf,nan
http://rosettacode.org/wiki/Determine_if_a_string_is_numeric
Determine if a string is numeric
Task Create a boolean function which takes in a string and tells whether it is a numeric string (floating point and negative numbers included) in the syntax the language uses for numeric literals or numbers converted from strings. Other tasks related to string operations: Metrics Array length String length Copy a string Empty string  (assignment) Counting Word frequency Letter frequency Jewels and stones I before E except after C Bioinformatics/base count Count occurrences of a substring Count how many vowels and consonants occur in a string Remove/replace XXXX redacted Conjugate a Latin verb Remove vowels from a string String interpolation (included) Strip block comments Strip comments from a string Strip a set of characters from a string Strip whitespace from a string -- top and tail Strip control codes and extended characters from a string Anagrams/Derangements/shuffling Word wheel ABC problem Sattolo cycle Knuth shuffle Ordered words Superpermutation minimisation Textonyms (using a phone text pad) Anagrams Anagrams/Deranged anagrams Permutations/Derangements Find/Search/Determine ABC words Odd words Word ladder Semordnilap Word search Wordiff  (game) String matching Tea cup rim text Alternade words Changeable words State name puzzle String comparison Unique characters Unique characters in each string Extract file extension Levenshtein distance Palindrome detection Common list elements Longest common suffix Longest common prefix Compare a list of strings Longest common substring Find common directory path Words from neighbour ones Change e letters to i in words Non-continuous subsequences Longest common subsequence Longest palindromic substrings Longest increasing subsequence Words containing "the" substring Sum of the digits of n is substring of n Determine if a string is numeric Determine if a string is collapsible Determine if a string is squeezable Determine if a string has all unique characters Determine if a string has all the same characters Longest substrings without repeating characters Find words which contains all the vowels Find words which contains most consonants Find words which contains more than 3 vowels Find words which first and last three letters are equals Find words which odd letters are consonants and even letters are vowels or vice_versa Formatting Substring Rep-string Word wrap String case Align columns Literals/String Repeat a string Brace expansion Brace expansion using ranges Reverse a string Phrase reversals Comma quibbling Special characters String concatenation Substring/Top and tail Commatizing numbers Reverse words in a string Suffixation of decimal numbers Long literals, with continuations Numerical and alphabetical suffixes Abbreviations, easy Abbreviations, simple Abbreviations, automatic Song lyrics/poems/Mad Libs/phrases Mad Libs Magic 8-ball 99 Bottles of Beer The Name Game (a song) The Old lady swallowed a fly The Twelve Days of Christmas Tokenize Text between Tokenize a string Word break problem Tokenize a string with escaping Split a character string based on change of character Sequences Show ASCII table De Bruijn sequences Self-referential sequences Generate lower case ASCII alphabet
#MiniScript
MiniScript
isNumeric = function(s) return s == "0" or s == "-0" or val(s) != 0 end function   print isNumeric("0") print isNumeric("42") print isNumeric("-3.14157") print isNumeric("5@*#!") print isNumeric("spam")
http://rosettacode.org/wiki/Determine_if_a_string_is_numeric
Determine if a string is numeric
Task Create a boolean function which takes in a string and tells whether it is a numeric string (floating point and negative numbers included) in the syntax the language uses for numeric literals or numbers converted from strings. Other tasks related to string operations: Metrics Array length String length Copy a string Empty string  (assignment) Counting Word frequency Letter frequency Jewels and stones I before E except after C Bioinformatics/base count Count occurrences of a substring Count how many vowels and consonants occur in a string Remove/replace XXXX redacted Conjugate a Latin verb Remove vowels from a string String interpolation (included) Strip block comments Strip comments from a string Strip a set of characters from a string Strip whitespace from a string -- top and tail Strip control codes and extended characters from a string Anagrams/Derangements/shuffling Word wheel ABC problem Sattolo cycle Knuth shuffle Ordered words Superpermutation minimisation Textonyms (using a phone text pad) Anagrams Anagrams/Deranged anagrams Permutations/Derangements Find/Search/Determine ABC words Odd words Word ladder Semordnilap Word search Wordiff  (game) String matching Tea cup rim text Alternade words Changeable words State name puzzle String comparison Unique characters Unique characters in each string Extract file extension Levenshtein distance Palindrome detection Common list elements Longest common suffix Longest common prefix Compare a list of strings Longest common substring Find common directory path Words from neighbour ones Change e letters to i in words Non-continuous subsequences Longest common subsequence Longest palindromic substrings Longest increasing subsequence Words containing "the" substring Sum of the digits of n is substring of n Determine if a string is numeric Determine if a string is collapsible Determine if a string is squeezable Determine if a string has all unique characters Determine if a string has all the same characters Longest substrings without repeating characters Find words which contains all the vowels Find words which contains most consonants Find words which contains more than 3 vowels Find words which first and last three letters are equals Find words which odd letters are consonants and even letters are vowels or vice_versa Formatting Substring Rep-string Word wrap String case Align columns Literals/String Repeat a string Brace expansion Brace expansion using ranges Reverse a string Phrase reversals Comma quibbling Special characters String concatenation Substring/Top and tail Commatizing numbers Reverse words in a string Suffixation of decimal numbers Long literals, with continuations Numerical and alphabetical suffixes Abbreviations, easy Abbreviations, simple Abbreviations, automatic Song lyrics/poems/Mad Libs/phrases Mad Libs Magic 8-ball 99 Bottles of Beer The Name Game (a song) The Old lady swallowed a fly The Twelve Days of Christmas Tokenize Text between Tokenize a string Word break problem Tokenize a string with escaping Split a character string based on change of character Sequences Show ASCII table De Bruijn sequences Self-referential sequences Generate lower case ASCII alphabet
#MIPS_Assembly
MIPS Assembly
  # $a0 char val # $a1 address pointer # $a2 PERIOD_HIT_FLAG # $a3 HAS_DIGITS_FLAG   .data ### CHANGE THIS STRING TO TEST DIFFERENT ONES... ### string: .asciiz "-.1236" s_false: .asciiz "False" s_true: .asciiz "True" .text main: set_up: #test for 0th char == 45 or 46 or 48...57 la $a1,string lb $a0,($a1) beq $a0,45,loop # == '-' beq $a0,46,loop # == '.' blt $a0,48,exit_false # isn't below the ascii range for chars '0'...'9' bgt $a0,57,exit_false # isn't above the ascii range for chars '0'...'9' loop: addi $a1,$a1,1 lb $a0,($a1) beqz $a0,exit_true # test for \0 null char beq $a0,46,period_test #test for a duplicate period blt $a0,48,exit_false #test for bgt $a0,57,exit_false la $a3,1 #set the HAS_DIGITS flag. This line is only reached because the # tests for period and - both jump back to start. j loop   exit_true: beqz $a3,exit_false la $a0,s_true la $v0,4 syscall   li $v0,10 syscall   exit_false: la $a0,s_false la $v0,4 syscall   li $v0,10 syscall   period_test: beq $a2,1,exit_false li $a2,1 j loop  
http://rosettacode.org/wiki/Digital_root
Digital root
The digital root, X {\displaystyle X} , of a number, n {\displaystyle n} , is calculated: find X {\displaystyle X} as the sum of the digits of n {\displaystyle n} find a new X {\displaystyle X} by summing the digits of X {\displaystyle X} , repeating until X {\displaystyle X} has only one digit. The additive persistence is the number of summations required to obtain the single digit. The task is to calculate the additive persistence and the digital root of a number, e.g.: 627615 {\displaystyle 627615} has additive persistence 2 {\displaystyle 2} and digital root of 9 {\displaystyle 9} ; 39390 {\displaystyle 39390} has additive persistence 2 {\displaystyle 2} and digital root of 6 {\displaystyle 6} ; 588225 {\displaystyle 588225} has additive persistence 2 {\displaystyle 2} and digital root of 3 {\displaystyle 3} ; 393900588225 {\displaystyle 393900588225} has additive persistence 2 {\displaystyle 2} and digital root of 9 {\displaystyle 9} ; The digital root may be calculated in bases other than 10. See Casting out nines for this wiki's use of this procedure. Digital root/Multiplicative digital root Sum digits of an integer Digital root sequence on OEIS Additive persistence sequence on OEIS Iterated digits squaring
#Tcl
Tcl
package require Tcl 8.5 proc digitalroot num { for {set p 0} {[string length $num] > 1} {incr p} { set num [::tcl::mathop::+ {*}[split $num ""]] } list $p $num }   foreach n {627615 39390 588225 393900588225} { lassign [digitalroot $n] p r puts [format "$n has additive persistence $p and digital root of $r"] }
http://rosettacode.org/wiki/Dot_product
Dot product
Task Create a function/use an in-built function, to compute the   dot product,   also known as the   scalar product   of two vectors. If possible, make the vectors of arbitrary length. As an example, compute the dot product of the vectors:   [1,  3, -5]     and   [4, -2, -1] If implementing the dot product of two vectors directly:   each vector must be the same length   multiply corresponding terms from each vector   sum the products   (to produce the answer) Related task   Vector products
#Phix
Phix
?sum(sq_mul({1,3,-5},{4,-2,-1}))
http://rosettacode.org/wiki/Department_numbers
Department numbers
There is a highly organized city that has decided to assign a number to each of their departments:   police department   sanitation department   fire department Each department can have a number between   1   and   7   (inclusive). The three department numbers are to be unique (different from each other) and must add up to   12. The Chief of the Police doesn't like odd numbers and wants to have an even number for his department. Task Write a computer program which outputs all valid combinations. Possible output   (for the 1st and 14th solutions): --police-- --sanitation-- --fire-- 2 3 7 6 5 1
#Lua
Lua
  print( "Fire", "Police", "Sanitation" ) sol = 0 for f = 1, 7 do for p = 1, 7 do for s = 1, 7 do if s + p + f == 12 and p % 2 == 0 and f ~= p and f ~= s and p ~= s then print( f, p, s ); sol = sol + 1 end end end end print( string.format( "\n%d solutions found", sol ) )  
http://rosettacode.org/wiki/Delete_a_file
Delete a file
Task Delete a file called "input.txt" and delete a directory called "docs". This should be done twice: once "here", i.e. in the current working directory and once in the filesystem root.
#Phix
Phix
without js -- (file i/o) constant root = iff(platform()=LINUX?"/":"C:\\") ?delete_file("input.txt") ?delete_file(root&"input.txt") ?remove_directory("docs") ?remove_directory(root&"docs")
http://rosettacode.org/wiki/Delete_a_file
Delete a file
Task Delete a file called "input.txt" and delete a directory called "docs". This should be done twice: once "here", i.e. in the current working directory and once in the filesystem root.
#PHP
PHP
<?php unlink('input.txt'); unlink('/input.txt'); rmdir('docs'); rmdir('/docs'); ?>
http://rosettacode.org/wiki/Detect_division_by_zero
Detect division by zero
Task Write a function to detect a   divide by zero error   without checking if the denominator is zero.
#Python
Python
def div_check(x, y): try: x / y except ZeroDivisionError: return True else: return False
http://rosettacode.org/wiki/Detect_division_by_zero
Detect division by zero
Task Write a function to detect a   divide by zero error   without checking if the denominator is zero.
#Q
Q
r:x%0 ?[1=sum r=(0n;0w;-0w);"division by zero detected";()]
http://rosettacode.org/wiki/Detect_division_by_zero
Detect division by zero
Task Write a function to detect a   divide by zero error   without checking if the denominator is zero.
#R
R
d <- 5/0 if ( !is.finite(d) ) { # it is Inf, -Inf, or NaN }
http://rosettacode.org/wiki/Determine_if_a_string_is_numeric
Determine if a string is numeric
Task Create a boolean function which takes in a string and tells whether it is a numeric string (floating point and negative numbers included) in the syntax the language uses for numeric literals or numbers converted from strings. Other tasks related to string operations: Metrics Array length String length Copy a string Empty string  (assignment) Counting Word frequency Letter frequency Jewels and stones I before E except after C Bioinformatics/base count Count occurrences of a substring Count how many vowels and consonants occur in a string Remove/replace XXXX redacted Conjugate a Latin verb Remove vowels from a string String interpolation (included) Strip block comments Strip comments from a string Strip a set of characters from a string Strip whitespace from a string -- top and tail Strip control codes and extended characters from a string Anagrams/Derangements/shuffling Word wheel ABC problem Sattolo cycle Knuth shuffle Ordered words Superpermutation minimisation Textonyms (using a phone text pad) Anagrams Anagrams/Deranged anagrams Permutations/Derangements Find/Search/Determine ABC words Odd words Word ladder Semordnilap Word search Wordiff  (game) String matching Tea cup rim text Alternade words Changeable words State name puzzle String comparison Unique characters Unique characters in each string Extract file extension Levenshtein distance Palindrome detection Common list elements Longest common suffix Longest common prefix Compare a list of strings Longest common substring Find common directory path Words from neighbour ones Change e letters to i in words Non-continuous subsequences Longest common subsequence Longest palindromic substrings Longest increasing subsequence Words containing "the" substring Sum of the digits of n is substring of n Determine if a string is numeric Determine if a string is collapsible Determine if a string is squeezable Determine if a string has all unique characters Determine if a string has all the same characters Longest substrings without repeating characters Find words which contains all the vowels Find words which contains most consonants Find words which contains more than 3 vowels Find words which first and last three letters are equals Find words which odd letters are consonants and even letters are vowels or vice_versa Formatting Substring Rep-string Word wrap String case Align columns Literals/String Repeat a string Brace expansion Brace expansion using ranges Reverse a string Phrase reversals Comma quibbling Special characters String concatenation Substring/Top and tail Commatizing numbers Reverse words in a string Suffixation of decimal numbers Long literals, with continuations Numerical and alphabetical suffixes Abbreviations, easy Abbreviations, simple Abbreviations, automatic Song lyrics/poems/Mad Libs/phrases Mad Libs Magic 8-ball 99 Bottles of Beer The Name Game (a song) The Old lady swallowed a fly The Twelve Days of Christmas Tokenize Text between Tokenize a string Word break problem Tokenize a string with escaping Split a character string based on change of character Sequences Show ASCII table De Bruijn sequences Self-referential sequences Generate lower case ASCII alphabet
#Mirah
Mirah
import java.text.NumberFormat import java.text.ParsePosition import java.util.Scanner   # this first example relies on catching an exception, # which is bad style and poorly performing in Java def is_numeric?(s:string) begin Double.parseDouble(s) return true rescue return false end end   puts '123 is numeric' if is_numeric?('123') puts '-123 is numeric' if is_numeric?('-123') puts '123.1 is numeric' if is_numeric?('123.1')   puts 'nil is not numeric' unless is_numeric?(nil) puts "'' is not numeric" unless is_numeric?('') puts 'abc is not numeric' unless is_numeric?('abc') puts '123- is not numeric' unless is_numeric?('123-') puts '1.2.3 is not numeric' unless is_numeric?('1.2.3')     # check every element of the string def is_numeric2?(s: string) if (s == nil || s.isEmpty()) return false end if (!s.startsWith('-')) if s.contains('-') return false end end   0.upto(s.length()-1) do |x| c = s.charAt(x) if ((x == 0) && (c == '-'.charAt(0))) # negative number elsif (c == '.'.charAt(0)) if (s.indexOf('.', x) > -1) return false # more than one period end elsif (!Character.isDigit(c)) return false end end true end     puts '123 is numeric' if is_numeric2?('123') puts '-123 is numeric' if is_numeric2?('-123') puts '123.1 is numeric' if is_numeric2?('123.1')   puts 'nil is not numeric' unless is_numeric2?(nil) puts "'' is not numeric" unless is_numeric2?('') puts 'abc is not numeric' unless is_numeric2?('abc') puts '123- is not numeric' unless is_numeric2?('123-') puts '1.2.3 is not numeric' unless is_numeric2?('1.2.3')       # use a regular expression def is_numeric3?(s:string) s == nil || s.matches("[-+]?\\d+(\\.\\d+)?") end   puts '123 is numeric' if is_numeric3?('123') puts '-123 is numeric' if is_numeric3?('-123') puts '123.1 is numeric' if is_numeric3?('123.1')   puts 'nil is not numeric' unless is_numeric3?(nil) puts "'' is not numeric" unless is_numeric3?('') puts 'abc is not numeric' unless is_numeric3?('abc') puts '123- is not numeric' unless is_numeric3?('123-') puts '1.2.3 is not numeric' unless is_numeric3?('1.2.3')     # use the positional parser in the java.text.NumberFormat object # (a more robust solution). If, after parsing, the parse position is at # the end of the string, we can deduce that the entire string was a # valid number. def is_numeric4?(s:string) return false if s == nil formatter = NumberFormat.getInstance() pos = ParsePosition.new(0) formatter.parse(s, pos) s.length() == pos.getIndex() end     puts '123 is numeric' if is_numeric4?('123') puts '-123 is numeric' if is_numeric4?('-123') puts '123.1 is numeric' if is_numeric4?('123.1')   puts 'nil is not numeric' unless is_numeric4?(nil) puts "'' is not numeric" unless is_numeric4?('') puts 'abc is not numeric' unless is_numeric4?('abc') puts '123- is not numeric' unless is_numeric4?('123-') puts '1.2.3 is not numeric' unless is_numeric4?('1.2.3')     # use the java.util.Scanner object. Very useful if you have to # scan multiple entries. Scanner also has similar methods for longs, # shorts, bytes, doubles, floats, BigIntegers, and BigDecimals as well # as methods for integral types where you may input a base/radix other than # 10 (10 is the default, which can be changed using the useRadix method). def is_numeric5?(s:string) return false if s == nil Scanner sc = Scanner.new(s) sc.hasNextDouble() end   puts '123 is numeric' if is_numeric5?('123') puts '-123 is numeric' if is_numeric5?('-123') puts '123.1 is numeric' if is_numeric5?('123.1')   puts 'nil is not numeric' unless is_numeric5?(nil) puts "'' is not numeric" unless is_numeric5?('') puts 'abc is not numeric' unless is_numeric5?('abc') puts '123- is not numeric' unless is_numeric5?('123-') puts '1.2.3 is not numeric' unless is_numeric5?('1.2.3')
http://rosettacode.org/wiki/Determine_if_a_string_is_numeric
Determine if a string is numeric
Task Create a boolean function which takes in a string and tells whether it is a numeric string (floating point and negative numbers included) in the syntax the language uses for numeric literals or numbers converted from strings. Other tasks related to string operations: Metrics Array length String length Copy a string Empty string  (assignment) Counting Word frequency Letter frequency Jewels and stones I before E except after C Bioinformatics/base count Count occurrences of a substring Count how many vowels and consonants occur in a string Remove/replace XXXX redacted Conjugate a Latin verb Remove vowels from a string String interpolation (included) Strip block comments Strip comments from a string Strip a set of characters from a string Strip whitespace from a string -- top and tail Strip control codes and extended characters from a string Anagrams/Derangements/shuffling Word wheel ABC problem Sattolo cycle Knuth shuffle Ordered words Superpermutation minimisation Textonyms (using a phone text pad) Anagrams Anagrams/Deranged anagrams Permutations/Derangements Find/Search/Determine ABC words Odd words Word ladder Semordnilap Word search Wordiff  (game) String matching Tea cup rim text Alternade words Changeable words State name puzzle String comparison Unique characters Unique characters in each string Extract file extension Levenshtein distance Palindrome detection Common list elements Longest common suffix Longest common prefix Compare a list of strings Longest common substring Find common directory path Words from neighbour ones Change e letters to i in words Non-continuous subsequences Longest common subsequence Longest palindromic substrings Longest increasing subsequence Words containing "the" substring Sum of the digits of n is substring of n Determine if a string is numeric Determine if a string is collapsible Determine if a string is squeezable Determine if a string has all unique characters Determine if a string has all the same characters Longest substrings without repeating characters Find words which contains all the vowels Find words which contains most consonants Find words which contains more than 3 vowels Find words which first and last three letters are equals Find words which odd letters are consonants and even letters are vowels or vice_versa Formatting Substring Rep-string Word wrap String case Align columns Literals/String Repeat a string Brace expansion Brace expansion using ranges Reverse a string Phrase reversals Comma quibbling Special characters String concatenation Substring/Top and tail Commatizing numbers Reverse words in a string Suffixation of decimal numbers Long literals, with continuations Numerical and alphabetical suffixes Abbreviations, easy Abbreviations, simple Abbreviations, automatic Song lyrics/poems/Mad Libs/phrases Mad Libs Magic 8-ball 99 Bottles of Beer The Name Game (a song) The Old lady swallowed a fly The Twelve Days of Christmas Tokenize Text between Tokenize a string Word break problem Tokenize a string with escaping Split a character string based on change of character Sequences Show ASCII table De Bruijn sequences Self-referential sequences Generate lower case ASCII alphabet
#mIRC_Scripting_Language
mIRC Scripting Language
var %value = 3 if (%value isnum) { echo -s %value is numeric. }
http://rosettacode.org/wiki/Digital_root
Digital root
The digital root, X {\displaystyle X} , of a number, n {\displaystyle n} , is calculated: find X {\displaystyle X} as the sum of the digits of n {\displaystyle n} find a new X {\displaystyle X} by summing the digits of X {\displaystyle X} , repeating until X {\displaystyle X} has only one digit. The additive persistence is the number of summations required to obtain the single digit. The task is to calculate the additive persistence and the digital root of a number, e.g.: 627615 {\displaystyle 627615} has additive persistence 2 {\displaystyle 2} and digital root of 9 {\displaystyle 9} ; 39390 {\displaystyle 39390} has additive persistence 2 {\displaystyle 2} and digital root of 6 {\displaystyle 6} ; 588225 {\displaystyle 588225} has additive persistence 2 {\displaystyle 2} and digital root of 3 {\displaystyle 3} ; 393900588225 {\displaystyle 393900588225} has additive persistence 2 {\displaystyle 2} and digital root of 9 {\displaystyle 9} ; The digital root may be calculated in bases other than 10. See Casting out nines for this wiki's use of this procedure. Digital root/Multiplicative digital root Sum digits of an integer Digital root sequence on OEIS Additive persistence sequence on OEIS Iterated digits squaring
#TI-83_BASIC
TI-83 BASIC
:ClrHome ­:1→X :Input ">",Str1 :Str1→Str2 :Repeat L≤1 :Disp Str1 :length(Str1→L :L→dim(L₁ :seq(expr(sub(Str1,A,1)),A,1,L)→L₁ :sum(L₁→N :{0,.5,1→L₂ :NL₂→L₃ :Med-Med L₂,L₃,Y₁ :Equ►String(Y₁,Str1 :sub(Str1,1,length(Str1)-3→Str1 :X+1→X :End :Pause :ClrHome :Disp Str2,"DIGITAL ROOT",expr(Str1),"ADDITIVE","PERSISTENCE",X :Pause
http://rosettacode.org/wiki/Digital_root
Digital root
The digital root, X {\displaystyle X} , of a number, n {\displaystyle n} , is calculated: find X {\displaystyle X} as the sum of the digits of n {\displaystyle n} find a new X {\displaystyle X} by summing the digits of X {\displaystyle X} , repeating until X {\displaystyle X} has only one digit. The additive persistence is the number of summations required to obtain the single digit. The task is to calculate the additive persistence and the digital root of a number, e.g.: 627615 {\displaystyle 627615} has additive persistence 2 {\displaystyle 2} and digital root of 9 {\displaystyle 9} ; 39390 {\displaystyle 39390} has additive persistence 2 {\displaystyle 2} and digital root of 6 {\displaystyle 6} ; 588225 {\displaystyle 588225} has additive persistence 2 {\displaystyle 2} and digital root of 3 {\displaystyle 3} ; 393900588225 {\displaystyle 393900588225} has additive persistence 2 {\displaystyle 2} and digital root of 9 {\displaystyle 9} ; The digital root may be calculated in bases other than 10. See Casting out nines for this wiki's use of this procedure. Digital root/Multiplicative digital root Sum digits of an integer Digital root sequence on OEIS Additive persistence sequence on OEIS Iterated digits squaring
#TypeScript
TypeScript
// Digital root   function rootAndPers(n: number, bas: number): [number, number] { var pers = 0; while (n >= bas) { var s = 0; do { s += n % bas; n = Math.floor(n / bas); } while (n > 0); pers++; n = s; } return [n, pers]; }   function intToString(n: number, wdth: number): string { sn = (Math.floor(n)).toString(); len = sn.length; return (wdth < len ? "#".repeat(wdth) : " ".repeat(wdth - len) + sn); }   for (var a of [1, 14, 267, 8128, 39390, 588225, 627615]) { var rp = rootAndPers(a, 10); console.log(intToString(a, 7) + intToString(rp[1], 6) + intToString(rp[0], 6)); }  
http://rosettacode.org/wiki/Dot_product
Dot product
Task Create a function/use an in-built function, to compute the   dot product,   also known as the   scalar product   of two vectors. If possible, make the vectors of arbitrary length. As an example, compute the dot product of the vectors:   [1,  3, -5]     and   [4, -2, -1] If implementing the dot product of two vectors directly:   each vector must be the same length   multiply corresponding terms from each vector   sum the products   (to produce the answer) Related task   Vector products
#Phixmonti
Phixmonti
def sq_mul 0 tolist var c len for var i i get rot i get rot * c swap 0 put var c endfor c enddef   def sq_sum 0 swap len for get rot + swap endfor swap enddef   1 3 -5 3 tolist 4 -2 -1 3 tolist sq_mul sq_sum pstack
http://rosettacode.org/wiki/Dot_product
Dot product
Task Create a function/use an in-built function, to compute the   dot product,   also known as the   scalar product   of two vectors. If possible, make the vectors of arbitrary length. As an example, compute the dot product of the vectors:   [1,  3, -5]     and   [4, -2, -1] If implementing the dot product of two vectors directly:   each vector must be the same length   multiply corresponding terms from each vector   sum the products   (to produce the answer) Related task   Vector products
#PHP
PHP
<?php function dot_product($v1, $v2) { if (count($v1) != count($v2)) throw new Exception('Arrays have different lengths'); return array_sum(array_map('bcmul', $v1, $v2)); }   echo dot_product(array(1, 3, -5), array(4, -2, -1)), "\n"; ?>
http://rosettacode.org/wiki/Department_numbers
Department numbers
There is a highly organized city that has decided to assign a number to each of their departments:   police department   sanitation department   fire department Each department can have a number between   1   and   7   (inclusive). The three department numbers are to be unique (different from each other) and must add up to   12. The Chief of the Police doesn't like odd numbers and wants to have an even number for his department. Task Write a computer program which outputs all valid combinations. Possible output   (for the 1st and 14th solutions): --police-- --sanitation-- --fire-- 2 3 7 6 5 1
#MAD
MAD
NORMAL MODE IS INTEGER PRINT COMMENT $ POLICE SANITATION FIRE$ THROUGH LOOP, FOR P=2, 2, P.G.7 THROUGH LOOP, FOR S=1, 1, S.G.7 THROUGH LOOP, FOR F=1, 1, F.G.7 WHENEVER P.E.S .OR. P.E.F .OR. S.E.F, TRANSFER TO LOOP WHENEVER P+S+F .E. 12, PRINT FORMAT OCC, P, S, F LOOP CONTINUE VECTOR VALUES OCC = $I6,S2,I10,S2,I4*$ END OF PROGRAM
http://rosettacode.org/wiki/Department_numbers
Department numbers
There is a highly organized city that has decided to assign a number to each of their departments:   police department   sanitation department   fire department Each department can have a number between   1   and   7   (inclusive). The three department numbers are to be unique (different from each other) and must add up to   12. The Chief of the Police doesn't like odd numbers and wants to have an even number for his department. Task Write a computer program which outputs all valid combinations. Possible output   (for the 1st and 14th solutions): --police-- --sanitation-- --fire-- 2 3 7 6 5 1
#Maple
Maple
#determines if i, j, k are exclusive numbers exclusive_numbers := proc(i, j, k) if (i = j) or (i = k) or (j = k) then return false; end if; return true; end proc;   #outputs all possible combinations of numbers that statisfy given conditions department_numbers := proc() local i, j, k; printf("Police Sanitation Fire\n"); for i to 7 do for j to 7 do k := 12 - i - j; if (k <= 7) and (k >= 1) and (i mod 2 = 0) and exclusive_numbers(i,j,k) then printf("%d %d %d\n", i, j, k); end if; end do; end do; end proc;   department_numbers();  
http://rosettacode.org/wiki/Delete_a_file
Delete a file
Task Delete a file called "input.txt" and delete a directory called "docs". This should be done twice: once "here", i.e. in the current working directory and once in the filesystem root.
#Picat
Picat
  import os.   del(Arg), directory(Arg) => rmdir(Arg).   del(Arg), file(Arg) => rm(Arg).   main(Args) => foreach (Arg in Args) del(Arg) end.  
http://rosettacode.org/wiki/Delete_a_file
Delete a file
Task Delete a file called "input.txt" and delete a directory called "docs". This should be done twice: once "here", i.e. in the current working directory and once in the filesystem root.
#PicoLisp
PicoLisp
(call 'rm "input.txt") (call 'rmdir "docs") (call 'rm "/input.txt") (call 'rmdir "/docs")
http://rosettacode.org/wiki/Delete_a_file
Delete a file
Task Delete a file called "input.txt" and delete a directory called "docs". This should be done twice: once "here", i.e. in the current working directory and once in the filesystem root.
#Pike
Pike
int main(){ rm("input.txt"); rm("/input.txt"); rm("docs"); rm("/docs"); }
http://rosettacode.org/wiki/Detect_division_by_zero
Detect division by zero
Task Write a function to detect a   divide by zero error   without checking if the denominator is zero.
#Racket
Racket
  #lang racket   (with-handlers ([exn:fail:contract:divide-by-zero? (λ (e) (displayln "Divided by zero"))]) (/ 1 0))  
http://rosettacode.org/wiki/Detect_division_by_zero
Detect division by zero
Task Write a function to detect a   divide by zero error   without checking if the denominator is zero.
#Raku
Raku
sub div($a, $b) { my $r; try { $r = $a / $b; CATCH { default { note "Unexpected exception, $_" } } } return $r // Nil; } say div(10,2); say div(1, sin(0));
http://rosettacode.org/wiki/Detect_division_by_zero
Detect division by zero
Task Write a function to detect a   divide by zero error   without checking if the denominator is zero.
#REBOL
REBOL
rebol [ Title: "Detect Divide by Zero" URL: http://rosettacode.org/wiki/Divide_by_Zero_Detection ]   ; The 'try' word returns an error object if the operation fails for ; whatever reason. The 'error?' word detects an error object and ; 'disarm' keeps it from triggering so I can analyze it to print the ; appropriate message. Otherwise, any reference to the error object ; will stop the program.   div-check: func [ "Attempt to divide two numbers, report result or errors as needed." x y /local result ] [ either error? result: try [x / y][ result: disarm result print ["Caught" result/type "error:" result/id] ] [ print [x "/" y "=" result] ] ]   div-check 12 2 ; An ordinary calculation. div-check 6 0 ; This will detect divide by zero. div-check "7" 0.0001 ; Other errors can be caught as well.
http://rosettacode.org/wiki/Determine_if_a_string_is_numeric
Determine if a string is numeric
Task Create a boolean function which takes in a string and tells whether it is a numeric string (floating point and negative numbers included) in the syntax the language uses for numeric literals or numbers converted from strings. Other tasks related to string operations: Metrics Array length String length Copy a string Empty string  (assignment) Counting Word frequency Letter frequency Jewels and stones I before E except after C Bioinformatics/base count Count occurrences of a substring Count how many vowels and consonants occur in a string Remove/replace XXXX redacted Conjugate a Latin verb Remove vowels from a string String interpolation (included) Strip block comments Strip comments from a string Strip a set of characters from a string Strip whitespace from a string -- top and tail Strip control codes and extended characters from a string Anagrams/Derangements/shuffling Word wheel ABC problem Sattolo cycle Knuth shuffle Ordered words Superpermutation minimisation Textonyms (using a phone text pad) Anagrams Anagrams/Deranged anagrams Permutations/Derangements Find/Search/Determine ABC words Odd words Word ladder Semordnilap Word search Wordiff  (game) String matching Tea cup rim text Alternade words Changeable words State name puzzle String comparison Unique characters Unique characters in each string Extract file extension Levenshtein distance Palindrome detection Common list elements Longest common suffix Longest common prefix Compare a list of strings Longest common substring Find common directory path Words from neighbour ones Change e letters to i in words Non-continuous subsequences Longest common subsequence Longest palindromic substrings Longest increasing subsequence Words containing "the" substring Sum of the digits of n is substring of n Determine if a string is numeric Determine if a string is collapsible Determine if a string is squeezable Determine if a string has all unique characters Determine if a string has all the same characters Longest substrings without repeating characters Find words which contains all the vowels Find words which contains most consonants Find words which contains more than 3 vowels Find words which first and last three letters are equals Find words which odd letters are consonants and even letters are vowels or vice_versa Formatting Substring Rep-string Word wrap String case Align columns Literals/String Repeat a string Brace expansion Brace expansion using ranges Reverse a string Phrase reversals Comma quibbling Special characters String concatenation Substring/Top and tail Commatizing numbers Reverse words in a string Suffixation of decimal numbers Long literals, with continuations Numerical and alphabetical suffixes Abbreviations, easy Abbreviations, simple Abbreviations, automatic Song lyrics/poems/Mad Libs/phrases Mad Libs Magic 8-ball 99 Bottles of Beer The Name Game (a song) The Old lady swallowed a fly The Twelve Days of Christmas Tokenize Text between Tokenize a string Word break problem Tokenize a string with escaping Split a character string based on change of character Sequences Show ASCII table De Bruijn sequences Self-referential sequences Generate lower case ASCII alphabet
#Modula-3
Modula-3
MODULE Numeric EXPORTS Main;   IMPORT IO, Fmt, Text;   PROCEDURE isNumeric(s: TEXT): BOOLEAN = BEGIN FOR i := 0 TO Text.Length(s) DO WITH char = Text.GetChar(s, i) DO IF i = 0 AND char = '-' THEN EXIT; END; IF char >= '0' AND char <= '9' THEN EXIT; END; RETURN FALSE; END; END; RETURN TRUE; END isNumeric;   BEGIN IO.Put("isNumeric(152) = " & Fmt.Bool(isNumeric("152")) & "\n"); IO.Put("isNumeric(-3.1415926) = " & Fmt.Bool(isNumeric("-3.1415926")) & "\n"); IO.Put("isNumeric(Foo123) = " & Fmt.Bool(isNumeric("Foo123")) & "\n"); END Numeric.
http://rosettacode.org/wiki/Digital_root
Digital root
The digital root, X {\displaystyle X} , of a number, n {\displaystyle n} , is calculated: find X {\displaystyle X} as the sum of the digits of n {\displaystyle n} find a new X {\displaystyle X} by summing the digits of X {\displaystyle X} , repeating until X {\displaystyle X} has only one digit. The additive persistence is the number of summations required to obtain the single digit. The task is to calculate the additive persistence and the digital root of a number, e.g.: 627615 {\displaystyle 627615} has additive persistence 2 {\displaystyle 2} and digital root of 9 {\displaystyle 9} ; 39390 {\displaystyle 39390} has additive persistence 2 {\displaystyle 2} and digital root of 6 {\displaystyle 6} ; 588225 {\displaystyle 588225} has additive persistence 2 {\displaystyle 2} and digital root of 3 {\displaystyle 3} ; 393900588225 {\displaystyle 393900588225} has additive persistence 2 {\displaystyle 2} and digital root of 9 {\displaystyle 9} ; The digital root may be calculated in bases other than 10. See Casting out nines for this wiki's use of this procedure. Digital root/Multiplicative digital root Sum digits of an integer Digital root sequence on OEIS Additive persistence sequence on OEIS Iterated digits squaring
#uBasic.2F4tH
uBasic/4tH
PRINT "Digital root of 627615 is "; FUNC(_FNdigitalroot(627615, 10)) ; PRINT " (additive persistence " ; Pop(); ")"   PRINT "Digital root of 39390 is "; FUNC(_FNdigitalroot(39390, 10)) ; PRINT " (additive persistence " ; Pop(); ")"   PRINT "Digital root of 588225 is "; FUNC(_FNdigitalroot(588225, 10)) ; PRINT " (additive persistence " ; Pop(); ")"   PRINT "Digital root of 9992 is "; FUNC(_FNdigitalroot(9992, 10)) ; PRINT " (additive persistence " ; Pop(); ")" END     _FNdigitalroot Param(2) Local (1) c@ = 0 Do Until a@ < b@ c@ = c@ + 1 a@ = FUNC(_FNdigitsum (a@, b@)) Loop Push (c@) ' That's how uBasic handles an extra Return (a@) ' return value: on the stack   _FNdigitsum Param (2) Local (2) d@ =0 Do While a@ # 0 c@ = a@ / b@ d@ = d@ + a@ - (c@ * b@) a@ = c@ Loop Return (d@)
http://rosettacode.org/wiki/Digital_root
Digital root
The digital root, X {\displaystyle X} , of a number, n {\displaystyle n} , is calculated: find X {\displaystyle X} as the sum of the digits of n {\displaystyle n} find a new X {\displaystyle X} by summing the digits of X {\displaystyle X} , repeating until X {\displaystyle X} has only one digit. The additive persistence is the number of summations required to obtain the single digit. The task is to calculate the additive persistence and the digital root of a number, e.g.: 627615 {\displaystyle 627615} has additive persistence 2 {\displaystyle 2} and digital root of 9 {\displaystyle 9} ; 39390 {\displaystyle 39390} has additive persistence 2 {\displaystyle 2} and digital root of 6 {\displaystyle 6} ; 588225 {\displaystyle 588225} has additive persistence 2 {\displaystyle 2} and digital root of 3 {\displaystyle 3} ; 393900588225 {\displaystyle 393900588225} has additive persistence 2 {\displaystyle 2} and digital root of 9 {\displaystyle 9} ; The digital root may be calculated in bases other than 10. See Casting out nines for this wiki's use of this procedure. Digital root/Multiplicative digital root Sum digits of an integer Digital root sequence on OEIS Additive persistence sequence on OEIS Iterated digits squaring
#UNIX_Shell
UNIX Shell
#!/usr/bin/env bash   numbers=(627615 39390 588225 393900588225 55) declare root   for number in "${numbers[@]}"; do declare -i iterations root="${number}" while [[ "${#root}" -ne 1 ]]; do root="$(( $(fold -w1 <<<"${root}" | xargs | sed 's/ /+/g') ))" iterations+=1 done echo -e "${number} has additive persistence ${iterations} and digital root ${root}" unset iterations done | column -t
http://rosettacode.org/wiki/Dot_product
Dot product
Task Create a function/use an in-built function, to compute the   dot product,   also known as the   scalar product   of two vectors. If possible, make the vectors of arbitrary length. As an example, compute the dot product of the vectors:   [1,  3, -5]     and   [4, -2, -1] If implementing the dot product of two vectors directly:   each vector must be the same length   multiply corresponding terms from each vector   sum the products   (to produce the answer) Related task   Vector products
#Picat
Picat
go => L1 = [1, 3, -5], L2 = [4, -2, -1],   println(dot_product=dot_product(L1,L2)), catch(println(dot_product([1,2,3,4],[1,2,3])),E, println(E)), nl.   dot_product(L1,L2) = _, L1.length != L2.length => throw($dot_product_not_same_length(L1,L2)). dot_product(L1,L2) = sum([L1[I]*L2[I] : I in 1..L1.length]).
http://rosettacode.org/wiki/Dot_product
Dot product
Task Create a function/use an in-built function, to compute the   dot product,   also known as the   scalar product   of two vectors. If possible, make the vectors of arbitrary length. As an example, compute the dot product of the vectors:   [1,  3, -5]     and   [4, -2, -1] If implementing the dot product of two vectors directly:   each vector must be the same length   multiply corresponding terms from each vector   sum the products   (to produce the answer) Related task   Vector products
#PicoLisp
PicoLisp
(de dotProduct (A B) (sum * A B) )   (dotProduct (1 3 -5) (4 -2 -1))
http://rosettacode.org/wiki/Department_numbers
Department numbers
There is a highly organized city that has decided to assign a number to each of their departments:   police department   sanitation department   fire department Each department can have a number between   1   and   7   (inclusive). The three department numbers are to be unique (different from each other) and must add up to   12. The Chief of the Police doesn't like odd numbers and wants to have an even number for his department. Task Write a computer program which outputs all valid combinations. Possible output   (for the 1st and 14th solutions): --police-- --sanitation-- --fire-- 2 3 7 6 5 1
#Mathematica.2FWolfram_Language
Mathematica/Wolfram Language
Select[Permutations[Range[7], {3}], Total[#] == 12 && EvenQ[First[#]] &]
http://rosettacode.org/wiki/Department_numbers
Department numbers
There is a highly organized city that has decided to assign a number to each of their departments:   police department   sanitation department   fire department Each department can have a number between   1   and   7   (inclusive). The three department numbers are to be unique (different from each other) and must add up to   12. The Chief of the Police doesn't like odd numbers and wants to have an even number for his department. Task Write a computer program which outputs all valid combinations. Possible output   (for the 1st and 14th solutions): --police-- --sanitation-- --fire-- 2 3 7 6 5 1
#Modula-2
Modula-2
MODULE DepartmentNumbers; FROM Conversions IMPORT IntToStr; FROM Terminal IMPORT WriteString,WriteLn,ReadChar;   PROCEDURE WriteInt(num : INTEGER); VAR str : ARRAY[0..16] OF CHAR; BEGIN IntToStr(num,str); WriteString(str); END WriteInt;   VAR i,j,k,count : INTEGER; BEGIN count:=0;   WriteString("Police Sanitation Fire"); WriteLn; WriteString("------ ---------- ----"); WriteLn;   FOR i:=2 TO 6 BY 2 DO FOR j:=1 TO 7 DO IF j=i THEN CONTINUE; END; FOR k:=1 TO 7 DO IF (k=i) OR (k=j) THEN CONTINUE; END; IF i+j+k # 12 THEN CONTINUE; END; WriteString(" "); WriteInt(i); WriteString(" "); WriteInt(j); WriteString(" "); WriteInt(k); WriteLn; INC(count); END; END; END;   WriteLn; WriteInt(count); WriteString(" valid combinations"); WriteLn;   ReadChar; END DepartmentNumbers.
http://rosettacode.org/wiki/Delete_a_file
Delete a file
Task Delete a file called "input.txt" and delete a directory called "docs". This should be done twice: once "here", i.e. in the current working directory and once in the filesystem root.
#PowerShell
PowerShell
# possible aliases for Remove-Item: rm, del, ri Remove-Item input.txt Remove-Item \input.txt # file system root   Remove-Item -Recurse docs # recurse for deleting folders including content Remove-Item -Recurse \docs
http://rosettacode.org/wiki/Delete_a_file
Delete a file
Task Delete a file called "input.txt" and delete a directory called "docs". This should be done twice: once "here", i.e. in the current working directory and once in the filesystem root.
#ProDOS
ProDOS
deletedirectory docs
http://rosettacode.org/wiki/Detect_division_by_zero
Detect division by zero
Task Write a function to detect a   divide by zero error   without checking if the denominator is zero.
#REXX
REXX
/*REXX program demonstrates detection and handling division by zero. */ signal on syntax /*handle all REXX syntax errors. */ x = sourceline() /*being cute, x=is the size of this pgm*/ y = x - x /*setting to zero the obtuse way. */ z = x / y /*this'll trigger it, furrrr shurrre. */ exit /*We're kaput. Ja vohl ! */ /*──────────────────────────────────────────────────────────────────────────────────────*/ err: if rc==42 then do; say /*first, check for a specific error. */ say center(' ***error*** ', 79, "═") say 'Division by zero detected at line ' @ , " and the REXX statement is:" say sourceLine(@) say exit 42 end say say center(' error! ', 79, "*") do #=1 for arg(); say; say arg(#); say end /*#*/ exit 13 /*──────────────────────────────────────────────────────────────────────────────────────*/ syntax: @=sigl; call err 'REXX program' condition("C") 'error', condition('D'), , 'REXX source statement (line' sigl"):", sourceLine(sigl)
http://rosettacode.org/wiki/Detect_division_by_zero
Detect division by zero
Task Write a function to detect a   divide by zero error   without checking if the denominator is zero.
#Ring
Ring
  Try see 9/0 Catch see "Catch!" + nl + cCatchError Done  
http://rosettacode.org/wiki/Determine_if_a_string_is_numeric
Determine if a string is numeric
Task Create a boolean function which takes in a string and tells whether it is a numeric string (floating point and negative numbers included) in the syntax the language uses for numeric literals or numbers converted from strings. Other tasks related to string operations: Metrics Array length String length Copy a string Empty string  (assignment) Counting Word frequency Letter frequency Jewels and stones I before E except after C Bioinformatics/base count Count occurrences of a substring Count how many vowels and consonants occur in a string Remove/replace XXXX redacted Conjugate a Latin verb Remove vowels from a string String interpolation (included) Strip block comments Strip comments from a string Strip a set of characters from a string Strip whitespace from a string -- top and tail Strip control codes and extended characters from a string Anagrams/Derangements/shuffling Word wheel ABC problem Sattolo cycle Knuth shuffle Ordered words Superpermutation minimisation Textonyms (using a phone text pad) Anagrams Anagrams/Deranged anagrams Permutations/Derangements Find/Search/Determine ABC words Odd words Word ladder Semordnilap Word search Wordiff  (game) String matching Tea cup rim text Alternade words Changeable words State name puzzle String comparison Unique characters Unique characters in each string Extract file extension Levenshtein distance Palindrome detection Common list elements Longest common suffix Longest common prefix Compare a list of strings Longest common substring Find common directory path Words from neighbour ones Change e letters to i in words Non-continuous subsequences Longest common subsequence Longest palindromic substrings Longest increasing subsequence Words containing "the" substring Sum of the digits of n is substring of n Determine if a string is numeric Determine if a string is collapsible Determine if a string is squeezable Determine if a string has all unique characters Determine if a string has all the same characters Longest substrings without repeating characters Find words which contains all the vowels Find words which contains most consonants Find words which contains more than 3 vowels Find words which first and last three letters are equals Find words which odd letters are consonants and even letters are vowels or vice_versa Formatting Substring Rep-string Word wrap String case Align columns Literals/String Repeat a string Brace expansion Brace expansion using ranges Reverse a string Phrase reversals Comma quibbling Special characters String concatenation Substring/Top and tail Commatizing numbers Reverse words in a string Suffixation of decimal numbers Long literals, with continuations Numerical and alphabetical suffixes Abbreviations, easy Abbreviations, simple Abbreviations, automatic Song lyrics/poems/Mad Libs/phrases Mad Libs Magic 8-ball 99 Bottles of Beer The Name Game (a song) The Old lady swallowed a fly The Twelve Days of Christmas Tokenize Text between Tokenize a string Word break problem Tokenize a string with escaping Split a character string based on change of character Sequences Show ASCII table De Bruijn sequences Self-referential sequences Generate lower case ASCII alphabet
#MUMPS
MUMPS
USER>WRITE +"1" 1 USER>WRITE +"1A" 1 USER>WRITE +"A1" 0 USER>WRITE +"1E" 1 USER>WRITE +"1E2" 100 USER>WRITE +"1EA24" 1 USER>WRITE +"1E3A" 1000 USER>WRITE +"1E-3" .001
http://rosettacode.org/wiki/Determine_if_a_string_is_numeric
Determine if a string is numeric
Task Create a boolean function which takes in a string and tells whether it is a numeric string (floating point and negative numbers included) in the syntax the language uses for numeric literals or numbers converted from strings. Other tasks related to string operations: Metrics Array length String length Copy a string Empty string  (assignment) Counting Word frequency Letter frequency Jewels and stones I before E except after C Bioinformatics/base count Count occurrences of a substring Count how many vowels and consonants occur in a string Remove/replace XXXX redacted Conjugate a Latin verb Remove vowels from a string String interpolation (included) Strip block comments Strip comments from a string Strip a set of characters from a string Strip whitespace from a string -- top and tail Strip control codes and extended characters from a string Anagrams/Derangements/shuffling Word wheel ABC problem Sattolo cycle Knuth shuffle Ordered words Superpermutation minimisation Textonyms (using a phone text pad) Anagrams Anagrams/Deranged anagrams Permutations/Derangements Find/Search/Determine ABC words Odd words Word ladder Semordnilap Word search Wordiff  (game) String matching Tea cup rim text Alternade words Changeable words State name puzzle String comparison Unique characters Unique characters in each string Extract file extension Levenshtein distance Palindrome detection Common list elements Longest common suffix Longest common prefix Compare a list of strings Longest common substring Find common directory path Words from neighbour ones Change e letters to i in words Non-continuous subsequences Longest common subsequence Longest palindromic substrings Longest increasing subsequence Words containing "the" substring Sum of the digits of n is substring of n Determine if a string is numeric Determine if a string is collapsible Determine if a string is squeezable Determine if a string has all unique characters Determine if a string has all the same characters Longest substrings without repeating characters Find words which contains all the vowels Find words which contains most consonants Find words which contains more than 3 vowels Find words which first and last three letters are equals Find words which odd letters are consonants and even letters are vowels or vice_versa Formatting Substring Rep-string Word wrap String case Align columns Literals/String Repeat a string Brace expansion Brace expansion using ranges Reverse a string Phrase reversals Comma quibbling Special characters String concatenation Substring/Top and tail Commatizing numbers Reverse words in a string Suffixation of decimal numbers Long literals, with continuations Numerical and alphabetical suffixes Abbreviations, easy Abbreviations, simple Abbreviations, automatic Song lyrics/poems/Mad Libs/phrases Mad Libs Magic 8-ball 99 Bottles of Beer The Name Game (a song) The Old lady swallowed a fly The Twelve Days of Christmas Tokenize Text between Tokenize a string Word break problem Tokenize a string with escaping Split a character string based on change of character Sequences Show ASCII table De Bruijn sequences Self-referential sequences Generate lower case ASCII alphabet
#Nanoquery
Nanoquery
def isNum(str) try double(str) return true catch return false end end
http://rosettacode.org/wiki/Digital_root
Digital root
The digital root, X {\displaystyle X} , of a number, n {\displaystyle n} , is calculated: find X {\displaystyle X} as the sum of the digits of n {\displaystyle n} find a new X {\displaystyle X} by summing the digits of X {\displaystyle X} , repeating until X {\displaystyle X} has only one digit. The additive persistence is the number of summations required to obtain the single digit. The task is to calculate the additive persistence and the digital root of a number, e.g.: 627615 {\displaystyle 627615} has additive persistence 2 {\displaystyle 2} and digital root of 9 {\displaystyle 9} ; 39390 {\displaystyle 39390} has additive persistence 2 {\displaystyle 2} and digital root of 6 {\displaystyle 6} ; 588225 {\displaystyle 588225} has additive persistence 2 {\displaystyle 2} and digital root of 3 {\displaystyle 3} ; 393900588225 {\displaystyle 393900588225} has additive persistence 2 {\displaystyle 2} and digital root of 9 {\displaystyle 9} ; The digital root may be calculated in bases other than 10. See Casting out nines for this wiki's use of this procedure. Digital root/Multiplicative digital root Sum digits of an integer Digital root sequence on OEIS Additive persistence sequence on OEIS Iterated digits squaring
#VBA
VBA
Option Base 1 Private Sub digital_root(n As Variant) Dim s As String, t() As Integer s = CStr(n) ReDim t(Len(s)) For i = 1 To Len(s) t(i) = Mid(s, i, 1) Next i Do dr = WorksheetFunction.Sum(t) s = CStr(dr) ReDim t(Len(s)) For i = 1 To Len(s) t(i) = Mid(s, i, 1) Next i persistence = persistence + 1 Loop Until Len(s) = 1 Debug.Print n; "has additive persistence"; persistence; "and digital root of "; dr & ";" End Sub Public Sub main() digital_root 627615 digital_root 39390 digital_root 588225 digital_root 393900588225# End Sub
http://rosettacode.org/wiki/Digital_root
Digital root
The digital root, X {\displaystyle X} , of a number, n {\displaystyle n} , is calculated: find X {\displaystyle X} as the sum of the digits of n {\displaystyle n} find a new X {\displaystyle X} by summing the digits of X {\displaystyle X} , repeating until X {\displaystyle X} has only one digit. The additive persistence is the number of summations required to obtain the single digit. The task is to calculate the additive persistence and the digital root of a number, e.g.: 627615 {\displaystyle 627615} has additive persistence 2 {\displaystyle 2} and digital root of 9 {\displaystyle 9} ; 39390 {\displaystyle 39390} has additive persistence 2 {\displaystyle 2} and digital root of 6 {\displaystyle 6} ; 588225 {\displaystyle 588225} has additive persistence 2 {\displaystyle 2} and digital root of 3 {\displaystyle 3} ; 393900588225 {\displaystyle 393900588225} has additive persistence 2 {\displaystyle 2} and digital root of 9 {\displaystyle 9} ; The digital root may be calculated in bases other than 10. See Casting out nines for this wiki's use of this procedure. Digital root/Multiplicative digital root Sum digits of an integer Digital root sequence on OEIS Additive persistence sequence on OEIS Iterated digits squaring
#VBScript
VBScript
Function digital_root(n) ap = 0 Do Until Len(n) = 1 x = 0 For i = 1 To Len(n) x = x + CInt(Mid(n,i,1)) Next n = x ap = ap + 1 Loop digital_root = "Additive Persistence = " & ap & vbCrLf &_ "Digital Root = " & n & vbCrLf End Function   WScript.StdOut.Write digital_root(WScript.Arguments(0))
http://rosettacode.org/wiki/Dot_product
Dot product
Task Create a function/use an in-built function, to compute the   dot product,   also known as the   scalar product   of two vectors. If possible, make the vectors of arbitrary length. As an example, compute the dot product of the vectors:   [1,  3, -5]     and   [4, -2, -1] If implementing the dot product of two vectors directly:   each vector must be the same length   multiply corresponding terms from each vector   sum the products   (to produce the answer) Related task   Vector products
#PL.2FI
PL/I
get (n); begin; declare (A(n), B(n)) float; declare dot_product float;   get list (A); get list (B); dot_product = sum(a*b); put (dot_product); end;
http://rosettacode.org/wiki/Dot_product
Dot product
Task Create a function/use an in-built function, to compute the   dot product,   also known as the   scalar product   of two vectors. If possible, make the vectors of arbitrary length. As an example, compute the dot product of the vectors:   [1,  3, -5]     and   [4, -2, -1] If implementing the dot product of two vectors directly:   each vector must be the same length   multiply corresponding terms from each vector   sum the products   (to produce the answer) Related task   Vector products
#Plain_English
Plain English
To run: Start up. Make an example vector and another example vector. Compute a dot product of the example vector and the other example vector. Destroy the example vector. Destroy the other example vector. Convert the dot product to a string. Write the string on the console. Wait for the escape key. Shut down.   An element is a thing with a number.   A vector is some elements.   To add a number to a vector: Allocate memory for an element. Put the number into the element's number. Append the element to the vector.   To multiply a vector by another vector: If the vector's count is not the other vector's count, exit. Get an element from the vector. Get another element from the other vector. Loop. If the element is nil, exit. Multiply the element's number by the other element's number. Put the element's next into the element. Put the other element's next into the other element. Repeat.   A sum is a number.   To find a sum of a vector: Get an element from the vector. Loop. If the element is nil, exit. Add the element's number to the sum. Put the element's next into the element. Repeat.   A product is a number.   To compute a dot product of a vector and another vector: If the vector's count is not the other vector's count, exit. Multiply the vector by the other vector. Find a sum of the vector. Put the sum into the dot product.   To make an example vector and another example vector: Add 1 to the example vector. Add 3 to the example vector. Add -5 to the example vector. Add 4 to the other example vector. Add -2 to the other example vector. Add -1 to the other example vector.
http://rosettacode.org/wiki/Department_numbers
Department numbers
There is a highly organized city that has decided to assign a number to each of their departments:   police department   sanitation department   fire department Each department can have a number between   1   and   7   (inclusive). The three department numbers are to be unique (different from each other) and must add up to   12. The Chief of the Police doesn't like odd numbers and wants to have an even number for his department. Task Write a computer program which outputs all valid combinations. Possible output   (for the 1st and 14th solutions): --police-- --sanitation-- --fire-- 2 3 7 6 5 1
#Mercury
Mercury
:- module department_numbers. :- interface.   :- import_module io. :- pred main(io::di, io::uo) is cc_multi.   :- implementation.   :- import_module int, list, solutions, string.   main(!IO) :- io.print_line("P S F", !IO), unsorted_aggregate(department_number, print_solution, !IO).   :- pred print_solution({int, int, int}::in, io::di, io::uo) is det.   print_solution({P, S, F}, !IO) :- io.format("%d %d %d\n", [i(P), i(S), i(F)], !IO).   :- pred department_number({int, int, int}::out) is nondet.   department_number({Police, Sanitation, Fire}) :- list.member(Police, [2, 4, 6]), list.member(Sanitation, 1 .. 7), list.member(Fire, 1 .. 7), Police \= Sanitation, Police \= Fire, Sanitation \= Fire, Police + Sanitation + Fire = 12.
http://rosettacode.org/wiki/Department_numbers
Department numbers
There is a highly organized city that has decided to assign a number to each of their departments:   police department   sanitation department   fire department Each department can have a number between   1   and   7   (inclusive). The three department numbers are to be unique (different from each other) and must add up to   12. The Chief of the Police doesn't like odd numbers and wants to have an even number for his department. Task Write a computer program which outputs all valid combinations. Possible output   (for the 1st and 14th solutions): --police-- --sanitation-- --fire-- 2 3 7 6 5 1
#Nim
Nim
type Solution = tuple[p, s, f: int]   iterator solutions(max, total: Positive): Solution = for p in countup(2, max, 2): for s in 1..max: if s == p: continue let f = total - p - s if f notin [p, s] and f in 1..max: yield (p, s, f)   echo "P S F" for sol in solutions(7, 12): echo sol.p, " ", sol.s, " ", sol.f
http://rosettacode.org/wiki/Delete_a_file
Delete a file
Task Delete a file called "input.txt" and delete a directory called "docs". This should be done twice: once "here", i.e. in the current working directory and once in the filesystem root.
#PureBasic
PureBasic
DeleteFile("input.txt") DeleteDirectory("docs","") ; needs to delete all included files DeleteFile("/input.txt") DeleteDirectory("/docs","*.*") ; deletes all files according to a pattern   DeleteDirectory("/docs","",#PB_FileSystem_Recursive) ; deletes all files and directories recursive
http://rosettacode.org/wiki/Delete_a_file
Delete a file
Task Delete a file called "input.txt" and delete a directory called "docs". This should be done twice: once "here", i.e. in the current working directory and once in the filesystem root.
#Python
Python
import os # current directory os.remove("output.txt") os.rmdir("docs") # root directory os.remove("/output.txt") os.rmdir("/docs")
http://rosettacode.org/wiki/Detect_division_by_zero
Detect division by zero
Task Write a function to detect a   divide by zero error   without checking if the denominator is zero.
#RPGIV
RPGIV
  dcl-c DIVIDE_BY_ZERO 00102;   dcl-s result zoned(5:2); dcl-s value1 zoned(5:2); dcl-s value2 zoned(5:2);   value1 = 10; value2 = 0;   monitor; eval(h) result = value1 / value2; // Using half rounding here for the eval result on-error DIVIDE_BY_ZERO; // Initialise the result to 0. Consider other messaging perhaps. result = 0; endmon;   *inlr = *on;  
http://rosettacode.org/wiki/Detect_division_by_zero
Detect division by zero
Task Write a function to detect a   divide by zero error   without checking if the denominator is zero.
#Ruby
Ruby
def div_check(x, y) begin x / y rescue ZeroDivisionError true else false end end
http://rosettacode.org/wiki/Detect_division_by_zero
Detect division by zero
Task Write a function to detect a   divide by zero error   without checking if the denominator is zero.
#Rust
Rust
fn test_division(numerator: u32, denominator: u32) { match numerator.checked_div(denominator) { Some(result) => println!("{} / {} = {}", numerator, denominator, result), None => println!("{} / {} results in a division by zero", numerator, denominator) } }   fn main() { test_division(5, 4); test_division(4, 0); }
http://rosettacode.org/wiki/Determine_if_a_string_is_numeric
Determine if a string is numeric
Task Create a boolean function which takes in a string and tells whether it is a numeric string (floating point and negative numbers included) in the syntax the language uses for numeric literals or numbers converted from strings. Other tasks related to string operations: Metrics Array length String length Copy a string Empty string  (assignment) Counting Word frequency Letter frequency Jewels and stones I before E except after C Bioinformatics/base count Count occurrences of a substring Count how many vowels and consonants occur in a string Remove/replace XXXX redacted Conjugate a Latin verb Remove vowels from a string String interpolation (included) Strip block comments Strip comments from a string Strip a set of characters from a string Strip whitespace from a string -- top and tail Strip control codes and extended characters from a string Anagrams/Derangements/shuffling Word wheel ABC problem Sattolo cycle Knuth shuffle Ordered words Superpermutation minimisation Textonyms (using a phone text pad) Anagrams Anagrams/Deranged anagrams Permutations/Derangements Find/Search/Determine ABC words Odd words Word ladder Semordnilap Word search Wordiff  (game) String matching Tea cup rim text Alternade words Changeable words State name puzzle String comparison Unique characters Unique characters in each string Extract file extension Levenshtein distance Palindrome detection Common list elements Longest common suffix Longest common prefix Compare a list of strings Longest common substring Find common directory path Words from neighbour ones Change e letters to i in words Non-continuous subsequences Longest common subsequence Longest palindromic substrings Longest increasing subsequence Words containing "the" substring Sum of the digits of n is substring of n Determine if a string is numeric Determine if a string is collapsible Determine if a string is squeezable Determine if a string has all unique characters Determine if a string has all the same characters Longest substrings without repeating characters Find words which contains all the vowels Find words which contains most consonants Find words which contains more than 3 vowels Find words which first and last three letters are equals Find words which odd letters are consonants and even letters are vowels or vice_versa Formatting Substring Rep-string Word wrap String case Align columns Literals/String Repeat a string Brace expansion Brace expansion using ranges Reverse a string Phrase reversals Comma quibbling Special characters String concatenation Substring/Top and tail Commatizing numbers Reverse words in a string Suffixation of decimal numbers Long literals, with continuations Numerical and alphabetical suffixes Abbreviations, easy Abbreviations, simple Abbreviations, automatic Song lyrics/poems/Mad Libs/phrases Mad Libs Magic 8-ball 99 Bottles of Beer The Name Game (a song) The Old lady swallowed a fly The Twelve Days of Christmas Tokenize Text between Tokenize a string Word break problem Tokenize a string with escaping Split a character string based on change of character Sequences Show ASCII table De Bruijn sequences Self-referential sequences Generate lower case ASCII alphabet
#Nemerle
Nemerle
using System; using System.Console;   module IsNumeric { IsNumeric( input : string) : bool { mutable meh = 0.0; // I don't want it, not going to use it, why force me to declare it? double.TryParse(input, out meh) }   Main() : void { def num = "-1.2345E6"; def not = "abc45"; WriteLine($"$num is numeric: $(IsNumeric(num))"); WriteLine($"$not is numeric: $(IsNumeric(not))"); } }
http://rosettacode.org/wiki/Determine_if_a_string_is_numeric
Determine if a string is numeric
Task Create a boolean function which takes in a string and tells whether it is a numeric string (floating point and negative numbers included) in the syntax the language uses for numeric literals or numbers converted from strings. Other tasks related to string operations: Metrics Array length String length Copy a string Empty string  (assignment) Counting Word frequency Letter frequency Jewels and stones I before E except after C Bioinformatics/base count Count occurrences of a substring Count how many vowels and consonants occur in a string Remove/replace XXXX redacted Conjugate a Latin verb Remove vowels from a string String interpolation (included) Strip block comments Strip comments from a string Strip a set of characters from a string Strip whitespace from a string -- top and tail Strip control codes and extended characters from a string Anagrams/Derangements/shuffling Word wheel ABC problem Sattolo cycle Knuth shuffle Ordered words Superpermutation minimisation Textonyms (using a phone text pad) Anagrams Anagrams/Deranged anagrams Permutations/Derangements Find/Search/Determine ABC words Odd words Word ladder Semordnilap Word search Wordiff  (game) String matching Tea cup rim text Alternade words Changeable words State name puzzle String comparison Unique characters Unique characters in each string Extract file extension Levenshtein distance Palindrome detection Common list elements Longest common suffix Longest common prefix Compare a list of strings Longest common substring Find common directory path Words from neighbour ones Change e letters to i in words Non-continuous subsequences Longest common subsequence Longest palindromic substrings Longest increasing subsequence Words containing "the" substring Sum of the digits of n is substring of n Determine if a string is numeric Determine if a string is collapsible Determine if a string is squeezable Determine if a string has all unique characters Determine if a string has all the same characters Longest substrings without repeating characters Find words which contains all the vowels Find words which contains most consonants Find words which contains more than 3 vowels Find words which first and last three letters are equals Find words which odd letters are consonants and even letters are vowels or vice_versa Formatting Substring Rep-string Word wrap String case Align columns Literals/String Repeat a string Brace expansion Brace expansion using ranges Reverse a string Phrase reversals Comma quibbling Special characters String concatenation Substring/Top and tail Commatizing numbers Reverse words in a string Suffixation of decimal numbers Long literals, with continuations Numerical and alphabetical suffixes Abbreviations, easy Abbreviations, simple Abbreviations, automatic Song lyrics/poems/Mad Libs/phrases Mad Libs Magic 8-ball 99 Bottles of Beer The Name Game (a song) The Old lady swallowed a fly The Twelve Days of Christmas Tokenize Text between Tokenize a string Word break problem Tokenize a string with escaping Split a character string based on change of character Sequences Show ASCII table De Bruijn sequences Self-referential sequences Generate lower case ASCII alphabet
#NetRexx
NetRexx
/* NetRexx */ options replace format comments java crossref symbols nobinary   numeric digits 20   loop n_ over getTestData() -- could have used n_.datatype('N') directly here... if isNumeric(n_) then msg = 'numeric' else msg = 'not numeric' say ('"'n_'"').right(25)':' msg end n_   return   -- ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ -- Pointless in NetRexx; the DATATYPE built-in-function is more powerful! method isNumeric(testString) public static returns boolean return testString.datatype('N')   -- ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ method getTestData() private static returns Rexx[]   -- Coercing numbers into the Rexx type has the effect of converting them to strings. -- NetRexx will still perform arithmetic on Rexx strings if those strings represent numbers. -- Notice that whitespace between the sign and the number are ignored even when inside a string constant testData = [ Rexx - ' one and a half', 1, 1.5, 1.5e+27, ' 1 ', ' 1.5 ', ' 1.5e+27 ', - '-one and a half', - 1, - 1.5, - 1.5e-27, ' - 1 ', '- 1.5 ', '- 1.5e-27 ', - '+one and a half', + 1, + 1.5, + 1.5e+27, ' + 1 ', '+ 1.5 ', '+ 1.5e+27 ', - 'Math Constants', - Math.PI, Math.E, - -Math.PI, -Math.E, - +Math.PI, +Math.E, - 'Numeric Constants', - Double.NaN, Double.POSITIVE_INFINITY, Double.NEGATIVE_INFINITY - ] return testData  
http://rosettacode.org/wiki/Digital_root
Digital root
The digital root, X {\displaystyle X} , of a number, n {\displaystyle n} , is calculated: find X {\displaystyle X} as the sum of the digits of n {\displaystyle n} find a new X {\displaystyle X} by summing the digits of X {\displaystyle X} , repeating until X {\displaystyle X} has only one digit. The additive persistence is the number of summations required to obtain the single digit. The task is to calculate the additive persistence and the digital root of a number, e.g.: 627615 {\displaystyle 627615} has additive persistence 2 {\displaystyle 2} and digital root of 9 {\displaystyle 9} ; 39390 {\displaystyle 39390} has additive persistence 2 {\displaystyle 2} and digital root of 6 {\displaystyle 6} ; 588225 {\displaystyle 588225} has additive persistence 2 {\displaystyle 2} and digital root of 3 {\displaystyle 3} ; 393900588225 {\displaystyle 393900588225} has additive persistence 2 {\displaystyle 2} and digital root of 9 {\displaystyle 9} ; The digital root may be calculated in bases other than 10. See Casting out nines for this wiki's use of this procedure. Digital root/Multiplicative digital root Sum digits of an integer Digital root sequence on OEIS Additive persistence sequence on OEIS Iterated digits squaring
#Visual_Basic_.NET
Visual Basic .NET
Module Module1   Function DigitalRoot(num As Long) As Tuple(Of Integer, Integer) Dim additivepersistence = 0 While num > 9 num = num.ToString().ToCharArray().Sum(Function(x) Integer.Parse(x)) additivepersistence = additivepersistence + 1 End While Return Tuple.Create(additivepersistence, CType(num, Integer)) End Function   Sub Main() Dim nums = {627615, 39390, 588225, 393900588225} For Each num In nums Dim t = DigitalRoot(num) Console.WriteLine("{0} has additive persistence {1} and digital root {2}", num, t.Item1, t.Item2) Next End Sub   End Module
http://rosettacode.org/wiki/Dot_product
Dot product
Task Create a function/use an in-built function, to compute the   dot product,   also known as the   scalar product   of two vectors. If possible, make the vectors of arbitrary length. As an example, compute the dot product of the vectors:   [1,  3, -5]     and   [4, -2, -1] If implementing the dot product of two vectors directly:   each vector must be the same length   multiply corresponding terms from each vector   sum the products   (to produce the answer) Related task   Vector products
#PostScript
PostScript
/dotproduct{ /x exch def /y exch def /sum 0 def /i 0 def x length y length eq %Check if both arrays have the same length { x length{ /sum x i get y i get mul sum add def /i i 1 add def }repeat sum == } { -1 == }ifelse }def
http://rosettacode.org/wiki/Dot_product
Dot product
Task Create a function/use an in-built function, to compute the   dot product,   also known as the   scalar product   of two vectors. If possible, make the vectors of arbitrary length. As an example, compute the dot product of the vectors:   [1,  3, -5]     and   [4, -2, -1] If implementing the dot product of two vectors directly:   each vector must be the same length   multiply corresponding terms from each vector   sum the products   (to produce the answer) Related task   Vector products
#PowerShell
PowerShell
  function dotproduct( $a, $b) { $a | foreach -Begin {$i = $res = 0} -Process { $res += $_*$b[$i++] } -End{$res} } dotproduct (1..2) (1..2) dotproduct (1..10) (11..20)  
http://rosettacode.org/wiki/Department_numbers
Department numbers
There is a highly organized city that has decided to assign a number to each of their departments:   police department   sanitation department   fire department Each department can have a number between   1   and   7   (inclusive). The three department numbers are to be unique (different from each other) and must add up to   12. The Chief of the Police doesn't like odd numbers and wants to have an even number for his department. Task Write a computer program which outputs all valid combinations. Possible output   (for the 1st and 14th solutions): --police-- --sanitation-- --fire-- 2 3 7 6 5 1
#Objeck
Objeck
class Program { function : Main(args : String[]) ~ Nil { sol := 1; "\t\tFIRE\tPOLICE\tSANITATION"->PrintLine(); for( f := 1; f < 8; f+=1; ) { for( p := 1; p < 8; p+=1; ) { for( s:= 1; s < 8; s+=1; ) { if( f <> p & f <> s & p <> s & ( p and 1 ) = 0 & ( f + s + p = 12 ) ) { "SOLUTION #{$sol}: \t{$f}\t{$p}\t{$s}"->PrintLine(); sol += 1; }; }; }; }; } }
http://rosettacode.org/wiki/Delete_a_file
Delete a file
Task Delete a file called "input.txt" and delete a directory called "docs". This should be done twice: once "here", i.e. in the current working directory and once in the filesystem root.
#R
R
file.remove("input.txt") file.remove("/input.txt")   # or file.remove("input.txt", "/input.txt")   # or unlink("input.txt"); unlink("/input.txt")   # directories needs the recursive flag unlink("docs", recursive = TRUE) unlink("/docs", recursive = TRUE)
http://rosettacode.org/wiki/Delete_a_file
Delete a file
Task Delete a file called "input.txt" and delete a directory called "docs". This should be done twice: once "here", i.e. in the current working directory and once in the filesystem root.
#Racket
Racket
  #lang racket   ;; here (delete-file "input.txt") (delete-directory "docs") (delete-directory/files "docs") ; recursive deletion   ;; in the root (delete-file "/input.txt") (delete-directory "/docs") (delete-directory/files "/docs")   ;; or in the root with relative paths (parameterize ([current-directory "/"]) (delete-file "input.txt") (delete-directory "docs") (delete-directory/files "docs"))  
http://rosettacode.org/wiki/Delete_a_file
Delete a file
Task Delete a file called "input.txt" and delete a directory called "docs". This should be done twice: once "here", i.e. in the current working directory and once in the filesystem root.
#Raku
Raku
unlink 'input.txt'; unlink '/input.txt'; rmdir 'docs'; rmdir '/docs';
http://rosettacode.org/wiki/Detect_division_by_zero
Detect division by zero
Task Write a function to detect a   divide by zero error   without checking if the denominator is zero.
#Scala
Scala
object DivideByZero extends Application {   def check(x: Int, y: Int): Boolean = { try { val result = x / y println(result) return false } catch { case x: ArithmeticException => { return true } } }   println("divided by zero = " + check(1, 0))   def check1(x: Int, y: Int): Boolean = { import scala.util.Try Try(y/x).isFailure } println("divided by zero = " + check1(1, 0))   }
http://rosettacode.org/wiki/Detect_division_by_zero
Detect division by zero
Task Write a function to detect a   divide by zero error   without checking if the denominator is zero.
#Seed7
Seed7
$ include "seed7_05.s7i"; include "float.s7i";   const proc: doDivide (in integer: numer, in integer: denom) is func begin block writeln(numer <& " div " <& denom <& " = " <& numer div denom); exception catch NUMERIC_ERROR: writeln("Division by zero detected."); end block; end func;   const proc: doDivide (in float: numer, in float: denom) is func local var float: quotient is 0.0; begin quotient := numer / denom; if quotient <> Infinity and quotient <> -Infinity then writeln(numer <& " / " <& denom <& " = " <& quotient); else writeln("Division by zero detected."); end if; end func;   const proc: main is func begin doDivide(10, 8); doDivide(1, 0); doDivide(10.0, 8.0); doDivide(1.0, 0.0); end func;
http://rosettacode.org/wiki/Determine_if_a_string_is_numeric
Determine if a string is numeric
Task Create a boolean function which takes in a string and tells whether it is a numeric string (floating point and negative numbers included) in the syntax the language uses for numeric literals or numbers converted from strings. Other tasks related to string operations: Metrics Array length String length Copy a string Empty string  (assignment) Counting Word frequency Letter frequency Jewels and stones I before E except after C Bioinformatics/base count Count occurrences of a substring Count how many vowels and consonants occur in a string Remove/replace XXXX redacted Conjugate a Latin verb Remove vowels from a string String interpolation (included) Strip block comments Strip comments from a string Strip a set of characters from a string Strip whitespace from a string -- top and tail Strip control codes and extended characters from a string Anagrams/Derangements/shuffling Word wheel ABC problem Sattolo cycle Knuth shuffle Ordered words Superpermutation minimisation Textonyms (using a phone text pad) Anagrams Anagrams/Deranged anagrams Permutations/Derangements Find/Search/Determine ABC words Odd words Word ladder Semordnilap Word search Wordiff  (game) String matching Tea cup rim text Alternade words Changeable words State name puzzle String comparison Unique characters Unique characters in each string Extract file extension Levenshtein distance Palindrome detection Common list elements Longest common suffix Longest common prefix Compare a list of strings Longest common substring Find common directory path Words from neighbour ones Change e letters to i in words Non-continuous subsequences Longest common subsequence Longest palindromic substrings Longest increasing subsequence Words containing "the" substring Sum of the digits of n is substring of n Determine if a string is numeric Determine if a string is collapsible Determine if a string is squeezable Determine if a string has all unique characters Determine if a string has all the same characters Longest substrings without repeating characters Find words which contains all the vowels Find words which contains most consonants Find words which contains more than 3 vowels Find words which first and last three letters are equals Find words which odd letters are consonants and even letters are vowels or vice_versa Formatting Substring Rep-string Word wrap String case Align columns Literals/String Repeat a string Brace expansion Brace expansion using ranges Reverse a string Phrase reversals Comma quibbling Special characters String concatenation Substring/Top and tail Commatizing numbers Reverse words in a string Suffixation of decimal numbers Long literals, with continuations Numerical and alphabetical suffixes Abbreviations, easy Abbreviations, simple Abbreviations, automatic Song lyrics/poems/Mad Libs/phrases Mad Libs Magic 8-ball 99 Bottles of Beer The Name Game (a song) The Old lady swallowed a fly The Twelve Days of Christmas Tokenize Text between Tokenize a string Word break problem Tokenize a string with escaping Split a character string based on change of character Sequences Show ASCII table De Bruijn sequences Self-referential sequences Generate lower case ASCII alphabet
#Nim
Nim
import strutils   proc isNumeric(s: string): bool = try: discard s.parseFloat() result = true except ValueError: result = false   const Strings = ["1", "3.14", "-100", "1e2", "Inf", "rose"]   for s in Strings: echo s, " is ", if s.isNumeric(): "" else: "not ", "numeric"
http://rosettacode.org/wiki/Determine_if_a_string_is_numeric
Determine if a string is numeric
Task Create a boolean function which takes in a string and tells whether it is a numeric string (floating point and negative numbers included) in the syntax the language uses for numeric literals or numbers converted from strings. Other tasks related to string operations: Metrics Array length String length Copy a string Empty string  (assignment) Counting Word frequency Letter frequency Jewels and stones I before E except after C Bioinformatics/base count Count occurrences of a substring Count how many vowels and consonants occur in a string Remove/replace XXXX redacted Conjugate a Latin verb Remove vowels from a string String interpolation (included) Strip block comments Strip comments from a string Strip a set of characters from a string Strip whitespace from a string -- top and tail Strip control codes and extended characters from a string Anagrams/Derangements/shuffling Word wheel ABC problem Sattolo cycle Knuth shuffle Ordered words Superpermutation minimisation Textonyms (using a phone text pad) Anagrams Anagrams/Deranged anagrams Permutations/Derangements Find/Search/Determine ABC words Odd words Word ladder Semordnilap Word search Wordiff  (game) String matching Tea cup rim text Alternade words Changeable words State name puzzle String comparison Unique characters Unique characters in each string Extract file extension Levenshtein distance Palindrome detection Common list elements Longest common suffix Longest common prefix Compare a list of strings Longest common substring Find common directory path Words from neighbour ones Change e letters to i in words Non-continuous subsequences Longest common subsequence Longest palindromic substrings Longest increasing subsequence Words containing "the" substring Sum of the digits of n is substring of n Determine if a string is numeric Determine if a string is collapsible Determine if a string is squeezable Determine if a string has all unique characters Determine if a string has all the same characters Longest substrings without repeating characters Find words which contains all the vowels Find words which contains most consonants Find words which contains more than 3 vowels Find words which first and last three letters are equals Find words which odd letters are consonants and even letters are vowels or vice_versa Formatting Substring Rep-string Word wrap String case Align columns Literals/String Repeat a string Brace expansion Brace expansion using ranges Reverse a string Phrase reversals Comma quibbling Special characters String concatenation Substring/Top and tail Commatizing numbers Reverse words in a string Suffixation of decimal numbers Long literals, with continuations Numerical and alphabetical suffixes Abbreviations, easy Abbreviations, simple Abbreviations, automatic Song lyrics/poems/Mad Libs/phrases Mad Libs Magic 8-ball 99 Bottles of Beer The Name Game (a song) The Old lady swallowed a fly The Twelve Days of Christmas Tokenize Text between Tokenize a string Word break problem Tokenize a string with escaping Split a character string based on change of character Sequences Show ASCII table De Bruijn sequences Self-referential sequences Generate lower case ASCII alphabet
#Objeck
Objeck
  class Numeric { function : Main(args : String[]) ~ Nil { if(args->Size() = 1) { IsNumeric(args[0])->PrintLine(); }; }   function : IsNumeric(str : String) ~ Bool { return str->IsFloat(); } }
http://rosettacode.org/wiki/Digital_root
Digital root
The digital root, X {\displaystyle X} , of a number, n {\displaystyle n} , is calculated: find X {\displaystyle X} as the sum of the digits of n {\displaystyle n} find a new X {\displaystyle X} by summing the digits of X {\displaystyle X} , repeating until X {\displaystyle X} has only one digit. The additive persistence is the number of summations required to obtain the single digit. The task is to calculate the additive persistence and the digital root of a number, e.g.: 627615 {\displaystyle 627615} has additive persistence 2 {\displaystyle 2} and digital root of 9 {\displaystyle 9} ; 39390 {\displaystyle 39390} has additive persistence 2 {\displaystyle 2} and digital root of 6 {\displaystyle 6} ; 588225 {\displaystyle 588225} has additive persistence 2 {\displaystyle 2} and digital root of 3 {\displaystyle 3} ; 393900588225 {\displaystyle 393900588225} has additive persistence 2 {\displaystyle 2} and digital root of 9 {\displaystyle 9} ; The digital root may be calculated in bases other than 10. See Casting out nines for this wiki's use of this procedure. Digital root/Multiplicative digital root Sum digits of an integer Digital root sequence on OEIS Additive persistence sequence on OEIS Iterated digits squaring
#Vlang
Vlang
import strconv   fn sum(ii u64, base int) int { mut s := 0 mut i := ii b64 := u64(base) for ; i > 0; i /= b64 { s += int(i % b64) } return s }   fn digital_root(n u64, base int) (int, int) { mut persistence := 0 mut root := int(n) for x := n; x >= u64(base); x = u64(root) { root = sum(x, base) persistence++ } return persistence, root }   // Normally the below would be moved to a *_test.go file and // use the testing package to be runnable as a regular test.   struct Test{ n string base int persistence int root int }   const test_cases = [ Test{"627615", 10, 2, 9}, Test{"39390", 10, 2, 6}, Test{"588225", 10, 2, 3}, Test{"393900588225", 10, 2, 9}, Test{"1", 10, 0, 1}, Test{"11", 10, 1, 2}, Test{"e", 16, 0, 0xe}, Test{"87", 16, 1, 0xf}, // From Applesoft BASIC example: Test{"DigitalRoot", 30, 2, 26}, // 26 is Q base 30 // From C++ example: Test{"448944221089", 10, 3, 1}, Test{"7e0", 16, 2, 0x6}, Test{"14e344", 16, 2, 0xf}, Test{"d60141", 16, 2, 0xa}, Test{"12343210", 16, 2, 0x1}, // From the D example: Test{"1101122201121110011000000", 3, 3, 1}, ]   fn main() { for tc in test_cases { n, err := strconv.common_parse_uint2(tc.n, tc.base, 64) if err != 0 { panic('ERROR') } p, r := digital_root(n, tc.base) println("${tc.n:12} (base ${tc.base:2}) has additive persistence $p and digital root ${strconv.format_int(i64(r), tc.base)}",) if p != tc.persistence || r != tc.root { panic("bad result: $tc $p $r") } } }
http://rosettacode.org/wiki/Digital_root
Digital root
The digital root, X {\displaystyle X} , of a number, n {\displaystyle n} , is calculated: find X {\displaystyle X} as the sum of the digits of n {\displaystyle n} find a new X {\displaystyle X} by summing the digits of X {\displaystyle X} , repeating until X {\displaystyle X} has only one digit. The additive persistence is the number of summations required to obtain the single digit. The task is to calculate the additive persistence and the digital root of a number, e.g.: 627615 {\displaystyle 627615} has additive persistence 2 {\displaystyle 2} and digital root of 9 {\displaystyle 9} ; 39390 {\displaystyle 39390} has additive persistence 2 {\displaystyle 2} and digital root of 6 {\displaystyle 6} ; 588225 {\displaystyle 588225} has additive persistence 2 {\displaystyle 2} and digital root of 3 {\displaystyle 3} ; 393900588225 {\displaystyle 393900588225} has additive persistence 2 {\displaystyle 2} and digital root of 9 {\displaystyle 9} ; The digital root may be calculated in bases other than 10. See Casting out nines for this wiki's use of this procedure. Digital root/Multiplicative digital root Sum digits of an integer Digital root sequence on OEIS Additive persistence sequence on OEIS Iterated digits squaring
#Wortel
Wortel
@let { sumDigits ^(@sum @arr) drootl &\@rangef [. sumDigits ^(\~>1 #@arr)]   droot ^(@last drootl) apers ^(#-drootl)   [  !console.log "[number]: [digital root] [additive persistence] [intermediate sums]" ~@each [627615 39390 588225 393900588225] &n !console.log "{n}: {!droot n} {!apers n} {@str !drootl n}" ] }
http://rosettacode.org/wiki/Dot_product
Dot product
Task Create a function/use an in-built function, to compute the   dot product,   also known as the   scalar product   of two vectors. If possible, make the vectors of arbitrary length. As an example, compute the dot product of the vectors:   [1,  3, -5]     and   [4, -2, -1] If implementing the dot product of two vectors directly:   each vector must be the same length   multiply corresponding terms from each vector   sum the products   (to produce the answer) Related task   Vector products
#Prolog
Prolog
dot_product(L1, L2, N) :- maplist(mult, L1, L2, P), sumlist(P, N).   mult(A,B,C) :- C is A*B.
http://rosettacode.org/wiki/Dot_product
Dot product
Task Create a function/use an in-built function, to compute the   dot product,   also known as the   scalar product   of two vectors. If possible, make the vectors of arbitrary length. As an example, compute the dot product of the vectors:   [1,  3, -5]     and   [4, -2, -1] If implementing the dot product of two vectors directly:   each vector must be the same length   multiply corresponding terms from each vector   sum the products   (to produce the answer) Related task   Vector products
#PureBasic
PureBasic
Procedure dotProduct(Array a(1),Array b(1)) Protected i, sum, length = ArraySize(a())   If ArraySize(a()) = ArraySize(b()) For i = 0 To length sum + a(i) * b(i) Next EndIf   ProcedureReturn sum EndProcedure   If OpenConsole() Dim a(2) Dim b(2)   a(0) = 1 : a(1) = 3 : a(2) = -5 b(0) = 4 : b(1) = -2 : b(2) = -1   PrintN(Str(dotProduct(a(),b())))   Print(#CRLF$ + #CRLF$ + "Press ENTER to exit"): Input() CloseConsole() EndIf