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Genetic Algorithm Library

, 7 Apr 2012 GPL3
A framework for genetic algorithms
galdemoapps.zip
TSP.exe
GeneticLibrary.dll
TestApp1.exe
TestApp2.exe
GaSchedule.exe
GaSchedule.cfg
GalDemoSource.zip
TestApp1
TestApp1.vcxproj.filters
TestApp2
TestApp2.vcxproj.filters
TSP
res
.svn
entries
prop-base
Toolbar.bmp.svn-base
TSP.ico.svn-base
props
text-base
Toolbar.bmp.svn-base
TSP.ico.svn-base
TSP.rc2.svn-base
tmp
prop-base
props
text-base
Toolbar.bmp
TSP.ico
TSP.vcxproj.filters
GaSchedule
Algorithm
GaSchedule.cfg
GaSchedule.vcxproj.filters
res
GaSchedule.ico
galdocumentation.zip
doxygen.png
Graphic
ab_cp.png
alg_st.png
a_cr.png
c_cp.png
i_cp.png
mp_cr.png
mv_cr.png
r_cp.png
s_cp.png
s_cr.png
galsource.zip
GeneticLibrary
build
release
gcc_bsd
gcc_linux
gcc_macos
gcc_solaris
icc_linux
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icc_win
mingw
msvc
scc_solaris
makefiles
gcc_bsd_debug
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gcc_linux_debug
gcc_linux_release
gcc_macos_debug
gcc_macos_release
gcc_solaris_debug
gcc_solaris_release
icc_linux_debug
icc_linux_release
icc_macos_debug
icc_macos_release
scc_solaris_debug
scc_solaris_release
source
vs
/*! \file ScalingOperations.cpp
    \brief This file contains implementation of scaling operations classes.
*/

/*
 * 
 * website: http://www.coolsoft-sd.com/
 * contact: support@coolsoft-sd.com
 *
 */

/*
 * Genetic Algorithm Library
 * Copyright (C) 2007-2008 Coolsoft Software Development
 * 
 * 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., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
 *
 */

#include "Population.h"
#include "ScalingOperations.h"

#include <math.h>

namespace Population
{
	namespace ScalingOperations
	{

		// Scales chromosome fitness value based on passed parameters
		float GaWindowScaling::operator ()(const GaScaledChromosome& chromosome,
			const GaPopulation& population,
			const GaScalingParams& parameters) const
		{
			float best = population.GetStatistics().GetValue( GSV_BEST_FITNESS_SCALED ).GetPrevious();
			float worst = population.GetStatistics().GetValue( GSV_WORST_FITNESS_SCALED ).GetPrevious();
			return chromosome.GetChromosome()->GetFitness() - ( best >= worst ? worst : best ) ;
		}

		// Returns TRUE if rescaling is needed for all chromosomes in population
		bool GaWindowScaling::NeedRescaling(const GaPopulation& population,
			const GaScalingParams& parameters) const
		{
			return population.GetStatistics().GetValue( GSV_WORST_FITNESS ).Changed();
		}

		// Scales chromosome fitness value based on passed parameters
		float GaExponentialScaling::operator ()(const GaScaledChromosome& chromosome,
			const GaPopulation& population,
			const GaScalingParams& parameters) const
		{
			float factor = ( (const GaScaleFactorParams&) parameters ).GetFactor();

			if( chromosome.GetChromosome()->GetFitness() == 0 && factor < 0 )
				return 0;

			return pow( chromosome.GetChromosome()->GetFitness(), factor );
		}

		// Returns TRUE if rescaling is needed for all chromosomes in population
		bool GaExponentialScaling::NeedRescaling(const GaPopulation& population,
			const GaScalingParams& parameters) const
		{
			GaScaledChromosome& c1 = population.GetAt( 0 );
			if( c1.GetScaledFitness() != (*this)( c1, population, parameters ) )
				return true;

			GaScaledChromosome& c2 = population.GetAt( 0 );
			if( c2.GetScaledFitness() != (*this)( c2, population, parameters ) )
				return true;

			return false;
		}

		// Scales chromosome fitness value based on passed parameters
		float GaLinearScaling::operator ()(const GaScaledChromosome& chromosome,
			const GaPopulation& population,
			const GaScalingParams& parameters) const
		{
			float a, b, d;

			float max = population.GetStatistics().GetValue( GSV_BEST_FITNESS ).GetPrevious();
			float avg = population.GetStatistics().GetValue( GSV_AVG_FITNESS ).GetPrevious();
			float min = population.GetStatistics().GetValue( GSV_WORST_FITNESS ).GetPrevious();

			float f = ( (const GaScaleFactorParams&)parameters ).GetFactor();

			if( min > ( f * avg - max ) / ( f - 1 ) )
			{
				d = max - avg;

				if( fabs( d ) < 0.00001 )
					a = 1, b = 0;
				else
				{
					a = avg / d;
					b = a * ( max - f * avg );
					a *= ( f - 1 );
				}
			}
			else
			{
				d = avg - min;

				if( fabs( d ) < 0.00001 )
					a = 1, b = 0;
				else
				{
					a = avg / d;
					b = -min * a;
				}
			}

			return a * chromosome.GetChromosome()->GetFitness() + b;
		}

		// Returns TRUE if rescaling is needed for all chromosomes in population
		bool GaLinearScaling::NeedRescaling(const GaPopulation& population,
			const GaScalingParams& parameters) const
		{
			if( population.GetStatistics().GetValue( GSV_BEST_FITNESS ).Changed() )
				return true;

			if( population.GetStatistics().GetValue( GSV_AVG_FITNESS ).Changed() )
				return true;

			if( population.GetStatistics().GetValue( GSV_WORST_FITNESS ).Changed() )
				return true;

			GaScaledChromosome& c = population.GetAt( 0 );
			return c.GetScaledFitness() != (*this)( c, population, parameters );
		}

		// Scales chromosome fitness value based on passed parameters
		float GaNormalizationScaling::operator ()(const GaScaledChromosome& chromosome,
			const GaPopulation& population,
			const GaScalingParams& parameters) const
		{
			return (float)( population.GetCurrentSize() - chromosome.GetIndex() );
		}

		// Returns TRUE if rescaling is needed for all chromosomes in population
		bool GaNormalizationScaling::NeedRescaling(const GaPopulation& population,
			const GaScalingParams& parameters) const
		{
			return population.GetStatistics().GetValue( GSV_POPULATION_SIZE ).Changed();
		}

	} // ScalingOperations
} // Population

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This article, along with any associated source code and files, is licensed under The GNU General Public License (GPLv3)

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About the Author

Mladen Janković
Software Developer
Serbia Serbia
No Biography provided

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