/*
* RapidMiner
*
* Copyright (C) 2001-2011 by Rapid-I and the contributors
*
* Complete list of developers available at our web site:
*
* http://rapid-i.com
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU Affero General Public License as published by
* the Free Software Foundation, either version 3 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 Affero General Public License for more details.
*
* You should have received a copy of the GNU Affero General Public License
* along with this program. If not, see http://www.gnu.org/licenses/.
*/
package com.rapidminer.operator.features.construction;
import java.util.LinkedList;
import java.util.List;
import com.rapidminer.example.Attribute;
import com.rapidminer.example.ExampleSet;
import com.rapidminer.generator.FeatureGenerator;
import com.rapidminer.operator.OperatorDescription;
import com.rapidminer.operator.OperatorException;
import com.rapidminer.parameter.ParameterType;
import com.rapidminer.parameter.ParameterTypeBoolean;
import com.rapidminer.parameter.ParameterTypeDouble;
import com.rapidminer.parameter.ParameterTypeInt;
import com.rapidminer.parameter.UndefinedParameterError;
import com.rapidminer.parameter.conditions.BooleanParameterCondition;
/**
* YAGGA is an acronym for Yet Another Generating Genetic Algorithm. Its
* approach to generating new attributes differs from the original one. The
* (generating) mutation can do one of the following things with different
* probabilities:
* <ul>
* <li>Probability {@rapidminer.math p/4}: Add a newly generated attribute to the
* feature vector</li>
* <li>Probability {@rapidminer.math p/4}: Add a randomly chosen original attribute
* to the feature vector</li>
* <li>Probability {@rapidminer.math p/2}: Remove a randomly chosen attribute from
* the feature vector</li>
* </ul>
* Thus it is guaranteed that the length of the feature vector can both grow and
* shrink. On average it will keep its original length, unless longer or shorter
* individuals prove to have a better fitness.
*
* Since this operator does not contain algorithms to extract features from
* value series, it is restricted to example sets with only single attributes.
* For (automatic) feature extraction from values series the value series plugin
* for RapidMiner written by Ingo Mierswa should be used. It is available at <a
* href="http://rapid-i.com">http://rapid-i.com</a>.
*
* @author Ingo Mierswa, Simon Fischer
*/
public class YAGGA extends AbstractGeneratingGeneticAlgorithm {
/** The parameter name for "Probability for mutation (-1: 1/n)." */
public static final String PARAMETER_P_MUTATION = "p_mutation";
public static final String PARAMETER_USE_HEURISTIC_MUTATION_PROBABILITY = "use_heuristic_mutation_probability";
/** The parameter name for "Max total number of attributes in all generations (-1: no maximum)." */
public static final String PARAMETER_MAX_TOTAL_NUMBER_OF_ATTRIBUTES = "max_total_number_of_attributes";
public static final String PARAMETER_LIMIT_MAX_TOTAL_NUMBER_OF_ATTRIBUTES = "limit_max_total_number_of_attributes";
public YAGGA(OperatorDescription description) {
super(description);
}
/**
* Since the mutation of YAGGA also creates new attributes this method
* returns null.
*/
@Override
protected ExampleSetBasedPopulationOperator getGeneratingPopulationOperator(ExampleSet exampleSet) {
return null;
}
/** Returns the generating mutation <code>PopulationOperator</code>. */
@Override
protected ExampleSetBasedPopulationOperator getMutationPopulationOperator(ExampleSet eSet) throws OperatorException {
List<FeatureGenerator> generators = getGenerators();
if (generators.size() == 0) {
getLogger().warning("No FeatureGenerators specified for " + getName() + ".");
} else {
getLogger().fine("YAGGA Generators: "+generators);
}
List<Attribute> attributes = new LinkedList<Attribute>();
for (Attribute attribute : eSet.getAttributes()) {
attributes.add(attribute);
}
double pMutation = getParameterAsBoolean(PARAMETER_USE_HEURISTIC_MUTATION_PROBABILITY) ? -1d : getParameterAsDouble(PARAMETER_P_MUTATION);
int maxNumberOfAttributes = getParameterAsBoolean(PARAMETER_LIMIT_MAX_TOTAL_NUMBER_OF_ATTRIBUTES)? getParameterAsInt(PARAMETER_MAX_TOTAL_NUMBER_OF_ATTRIBUTES) : -1;
return new GeneratingMutation(attributes, pMutation, maxNumberOfAttributes, generators, getRandom());
}
/** Creates a initial population. */
@Override
public ExampleSetBasedPopulation createInitialPopulation(ExampleSet es) throws UndefinedParameterError {
ExampleSetBasedPopulation population = super.createInitialPopulation(es);
ExampleSetBasedPopulation popRemovedDeselected = new ExampleSetBasedPopulation();
for (int i = 0; i < population.getNumberOfIndividuals(); i++) {
popRemovedDeselected.add(new ExampleSetBasedIndividual(population.get(i).getExampleSet().createCleanClone()));
}
return popRemovedDeselected;
}
@Override
public List<ParameterType> getParameterTypes() {
List<ParameterType> types = new LinkedList<ParameterType>();
ParameterType type = new ParameterTypeBoolean(PARAMETER_LIMIT_MAX_TOTAL_NUMBER_OF_ATTRIBUTES, "Indicates if the total number of attributes in all generations should be limited.", false);
types.add(type);
type = new ParameterTypeInt(PARAMETER_MAX_TOTAL_NUMBER_OF_ATTRIBUTES, "Max total number of attributes in all generations.", 1, Integer.MAX_VALUE, 1);
type.registerDependencyCondition(new BooleanParameterCondition(this, PARAMETER_LIMIT_MAX_TOTAL_NUMBER_OF_ATTRIBUTES, false, true));
types.add(type);
types.addAll(super.getParameterTypes());
types.add(new ParameterTypeBoolean(PARAMETER_USE_HEURISTIC_MUTATION_PROBABILITY, "If checked the probability for mutations will be chosen as 1/number of attributes.", true));
type = new ParameterTypeDouble(PARAMETER_P_MUTATION, "Probability for mutation.", 0, 1, true);
type.registerDependencyCondition(new BooleanParameterCondition(this, PARAMETER_USE_HEURISTIC_MUTATION_PROBABILITY, true, false));
types.add(type);
return types;
}
}