++ed by:
Kevin Ryde


Math::Factor::XS - Factorize numbers and calculate matching multiplications


 use Math::Factor::XS ':all';
 # or
 use Math::Factor::XS qw(factors prime_factors matches);

 $number = 30107;

 @factors = factors($number);
 @primes = prime_factors($number);
 @matches = matches($number, \@factors);

 print "$factors[1]\n";
 print "$number == $matches[0][0] * $matches[0][1]\n";


Math::Factor::XS factorizes numbers by applying trial divisions.



Find all factors (ie. divisors) of a number.

 @factors = factors($number);

The number is factorized and its factors are returned as a list. For example,

 @factors = factors(30);
 #  @factors = (2, 3, 5, 6, 10, 15);


Find prime factors of a number.

 @factors = prime_factors($number);

The number is factorized and its prime factors are returned as a list. Multiplying the list together gives $number. For example,

 @primes = prime_factors(90);
 #  @primes = (2, 3, 3, 5);


Return the count of prime factors of a number. This is the number of values returned by prime_factors().

 my $count = count_prime_factors($number);


Calculates matching multiplications.

 @matches = matches($number, \@factors, { skip_multiples => [0|1] });

The factors will be multiplied against each other and all combinations that equal the number itself will be returned as a two-dimensional list. The matches are accessible through the indexes; for example, the first two numbers that matched the number may be accessed by $matches[0][0] and $matches[0][1], the second pair by $matches[1][0] and $matches[1][1], and so on.

The hashref provided at the end is optional. If skip_multiples is set to a true value, then matching multiplications that contain multiplicated small factors will be discarded. Example:

 11 * 2737 == 30107 # accepted
 77 * 391  == 30107 # discarded

Direct use of $Math::Factor::XS::Skip_multiple does no longer have an effect as it has been superseded by skip_multiples.



factors(), matches() and prime_factors() are exportable.


:all - *()


Steven Schubiger <schubiger@cpan.org>


This program is free software; you may redistribute it and/or modify it under the same terms as Perl itself.

See http://dev.perl.org/licenses/

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