incest.h

free library of genetic algorithms

/*
    cpplibga, free library of genetic algorithms.
    Copyright (C) 2003  Burger Y.A. (aka Jo Kruger)

    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation; either version 2 of the License, or
    (at your option) any later version.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with this program; if not, write to the Free Software
    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

Contacts:

   address: planet Terra
   e-mail:  [e-mail]
            [e-mail]
*/

#ifndef __CPPLIBGA_MUTATION_INCEST_H__
#define __CPPLIBGA_MUTATION_INCEST_H__

#include <stdlib.h>

#include <cpplibga/Types.h>

namespace cpplibga
{
    namespace mutation
    {
	class Incest
	{
	    public:

                Incest()
                {
                    setMutationProbability(0.1);
                    setMutationDensity(0.1);
                }
            
		void setMutationProbability(double x) {probability=x;probabilityMulRAND_MAX=x*RAND_MAX;}
		double getMutationProbability() const {return probability;}
		
                void setMutationDensity(double x) {density=x;densityMulRAND_MAX=x*RAND_MAX;}
                double getMutationDensity() const {return density;}
                
		template<typename S, typename P>
		void mutate(S* solution,
			    const P& pair)
		{
		    if(rand() < probabilityMulRAND_MAX)
		    {
                        genotype_size_type size=S::size();
                        genotype_size_type count=0;
                        genotype_size_type i;
                        
                        for(i=0; i<size; ++i)
                        {
                            if(pair.first->getGene(i) == pair.second->getGene(i)){++count;}
                        }
                        
                        int p=static_cast<int>(densityMulRAND_MAX*count/size);
                        for(i=0; i<size; ++i)
                        {
			    if(rand() < p){solution->invertGene(i);}
                        }
		    }
		}
	    
	    private:

		double probability;
                double probabilityMulRAND_MAX;
                
                double density;
                double densityMulRAND_MAX;
	};
    }
}

#endif