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use strict;
use base qw(Exporter);
use boolean qw(true);
use Carp qw(croak);
use List::MoreUtils qw(all);
use Params::Validate ':all';
use Scalar::Util qw(looks_like_number);
our ($VERSION, @EXPORT_OK, %EXPORT_TAGS);
$VERSION = '0.40';
@EXPORT_OK = qw(factors matches prime_factors count_prime_factors);
%EXPORT_TAGS = (all => \@EXPORT_OK);
validation_options(
on_fail => sub
{
my ($error) = @_;
chomp $error;
croak $error;
});
my $positive_nums = sub
{
all { looks_like_number($_) && ($_ >= 0) }
ref $_[0] ? @{$_[0]} : ($_[0]);
};
sub matches
{
validate_pos(@_,
{ type => SCALAR,
callbacks => {
'is a positive number' =>
$positive_nums,
},
},
{ type => ARRAYREF,
callbacks => {
'factors are positive numbers' => sub
{
my $factors = shift;
!@$factors or $positive_nums->($factors);
},
},
},
{ type => HASHREF,
optional => true,
},
);
return xs_matches(@_);
}
require XSLoader;
XSLoader::load(__PACKAGE__, $VERSION);
1;
__END__
=head1 NAME
Math::Factor::XS - Factorize numbers and calculate matching multiplications
=head1 SYNOPSIS
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] * $matches[0][1]\n";
=head1 DESCRIPTION
C<Math::Factor::XS> factorizes numbers by applying trial divisions.
=head1 FUNCTIONS
=head2 factors
Find all factors (ie. divisors) of a number.
@factors = factors($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);
=head2 prime_factors
Find prime factors of a number.
@factors = prime_factors($number);
The number is factorized and its prime factors are returned as a list.
Multiplying the list together gives C<$number>. For example,
@primes = prime_factors(90);
# @primes = (2, 3, 3, 5);
=head2 count_prime_factors
Return the count of prime factors of a number. This is the number of values
returned by C<prime_factors()>.
my $count = count_prime_factors($number);
=head2 matches
Calculates matching multiplications.
@matches = matches($number, \@factors, { skip_multiples => [0|1] });
The factors will be multiplied against each other and all combinations
that equal the number itself will be returned as a two-dimensional list.
The matches are accessible through the indexes; for example, the first
two numbers that matched the number may be accessed by C<$matches[0][0]>
and C<$matches[0][1]>, the second pair by C<$matches[1][0]> and
C<$matches[1][1]>, and so on.
The hashref provided at the end is optional. If C<skip_multiples>
is set to a true value, then matching multiplications that contain
multiplicated small factors will be discarded. Example:
11 * 2737 == 30107 # accepted
77 * 391 == 30107 # discarded
Direct use of C<$Math::Factor::XS::Skip_multiple> does no longer
have an effect as it has been superseded by C<skip_multiples>.
=head1 EXPORT
=head2 Functions
C<factors()>, C<matches()> and C<prime_factors()> are exportable.
=head2 Tags
C<:all - *()>
=head1 AUTHOR
Steven Schubiger <schubiger@cpan.org>
=head1 LICENSE
This program is free software; you may redistribute it and/or
modify it under the same terms as Perl itself.
=cut