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1 non-PAUSE user.

J. J. Merelo-Guervós
and 1 contributors

NAME Algorithm::Evolutionary::Op::Breeder_Diverser - Like Breeder, only it tries to cross only individuals that are different


    use Algorithm::Evolutionary qw( Individual::BitString 
      Op::Mutation Op::Crossover

    use Algorithm::Evolutionary::Utils qw(average);

    my @pop;
    my $number_of_bits = 20;
    my $population_size = 20;
    my $replacement_rate = 0.5;
    for ( 1..$population_size ) {
      my $indi = new Algorithm::Evolutionary::Individual::BitString $number_of_bits ; #Creates random individual
      $indi->evaluate( $onemax );
      push( @pop, $indi );

    my $m =  new Algorithm::Evolutionary::Op::Mutation 0.5;
    my $c = new Algorithm::Evolutionary::Op::Crossover; #Classical 2-point crossover

    my $selector = new Algorithm::Evolutionary::Op::RouletteWheel $population_size; #One of the possible selectors

    my $generation = 
      new Algorithm::Evolutionary::Op::Breeder_Diverser( $selector, [$m, $c] );

    my @sortPop = sort { $b->Fitness() <=> $a->Fitness() } @pop;
    my $bestIndi = $sortPop[0];
    my $previous_average = average( \@sortPop );
    $generation->apply( \@sortPop );

Base Class



Breeder part of the evolutionary algorithm; takes a population and returns another created from the first. Different from Algorithm::Evolutionary::Op::Breeder: tries to avoid crossover among the same individuals and also re-creating an individual already in the pool. In that sense it "diverses", tries to diversify the population. In general, it works better in environments where high diversity is needed (like, for instance, in Algorithm::MasterMind.


new( $ref_to_operator_array[, $selector = new Algorithm::Evolutionary::Op::Tournament_Selection 2 ] )

Creates a breeder, with a selector and array of operators

apply( $population[, $how_many || $population_size] )

Applies the algorithm to the population, which should have been evaluated first; checks that it receives a ref-to-array as input, croaks if it does not. Returns a sorted, culled, evaluated population for next generation.

It is valid only for string-denominated chromosomes. Checks that the offspring is different from parents before inserting it.


More or less in the same ballpark, alternatives to this one


  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: 2013/01/07 13:54:20 $ 
  $Header: /media/Backup/Repos/opeal/opeal/Algorithm-Evolutionary/lib/Algorithm/Evolutionary/Op/Breeder_Diverser.pm,v 1.7 2013/01/07 13:54:20 jmerelo Exp $ 
  $Author: jmerelo $ 
  $Revision: 1.7 $