use strict;
use warnings;
=head1 NAME
Algorithm::Evolutionary::Op::QuadXOver - N-point crossover operator that changes operands
=head1 SYNOPSIS
my $xmlStr3=<<EOC;
<op name='QuadXOver' type='binary' rate='1'>
<param name='numPoints' value='2' /> #Max is 2, anyways
</op>
EOC
my $ref3 = XMLin($xmlStr3);
my $op3 = Algorithm::Evolutionary::Op::Base->fromXML( $ref3 );
print $op3->asXML(), "\n";
my $indi = new Algorithm::Evolutionary::Individual::BitString 10;
my $indi2 = $indi->clone();
my $indi3 = $indi->clone(); #Operands are modified, so better to clone them
$op3->apply( $indi2, $indi3 );
my $op4 = new Algorithm::Evolutionary::Op::QuadXOver 1; #QuadXOver with 1 crossover points
=head1 Base Class
L<Algorithm::Evolutionary::Op::Base|Algorithm::Evolutionary::Op::Base>
=head1 DESCRIPTION
Crossover operator for a GA, takes args by reference and issues two
children from two parents
=head1 METHODS
=cut
package Algorithm::Evolutionary::Op::QuadXOver;
use lib qw( ../../.. );
our $VERSION = sprintf "%d.1%02d", q$Revision: 3.4 $ =~ /(\d+)\.(\d+)/g; # Hack for avoiding version mismatch
use Carp;
use base 'Algorithm::Evolutionary::Op::Crossover';
#Class-wide constants
our $APPLIESTO = 'Algorithm::Evolutionary::Individual::String';
our $ARITY = 2;
=head2 apply( $parent_1, $parent_2 )
Same as L<Algorithm::Evolutionary::Op::Crossover>, but changes
parents, does not return anything; that is, $parent_1 and $parent_2
interchange genetic material.
=cut
sub apply ($$){
my $self = shift;
my $victim = shift || croak "No victim here!";
my $victim2 = shift || croak "No victim here!";
# croak "Incorrect type ".(ref $victim) if !$self->check($victim);
# croak "Incorrect type ".(ref $victim2) if !$self->check($victim2);
my $minlen = ( length( $victim->{_str} ) > length( $victim2->{_str} ) )?
length( $victim2->{_str} ): length( $victim->{_str} );
my $pt1 = 1+int( rand( $minlen - 1 ) ); # first crossover point shouldn't be 0
my $range;
if ( $self->{_numPoints} > 1 ) {
$range= 1 + int( rand( $minlen - $pt1 ) );
} else {
$range = $minlen - $pt1;
}
# print "Puntos: $pt1, $range \n";
my $str = $victim->{_str};
substr( $victim->{_str}, $pt1, $range ) = substr( $victim2->{_str}, $pt1, $range );
substr( $victim2->{_str}, $pt1, $range ) = substr( $str, $pt1, $range );
$victim->Fitness( undef );
$victim2->Fitness( undef );
return undef; #As a warning that you should not expect anything
}
=head1 Copyright
This file is released under the GPL. See the LICENSE file included in this distribution,
or go to http://www.fsf.org/licenses/gpl.txt
CVS Info: $Date: 2010/12/08 17:34:22 $
$Header: /media/Backup/Repos/opeal/opeal/Algorithm-Evolutionary/lib/Algorithm/Evolutionary/Op/QuadXOver.pm,v 3.4 2010/12/08 17:34:22 jmerelo Exp $
$Author: jmerelo $
$Revision: 3.4 $
$Name $
=cut