home | career | drupal | java | mac | mysql | perl | scala | uml | unix  

Java example source code file (NPointCrossoverTest.java)

This example Java source code file (NPointCrossoverTest.java) is included in the alvinalexander.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" TM.

Learn more about this Java project at its project page.

Java - Java tags/keywords

binarychromosome, chromosomepair, crossoverpolicy, dummybinarychromosome, integer, list, npointcrossover, npointcrossovertest, test, util

The NPointCrossoverTest.java Java example source code

/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package org.apache.commons.math3.genetics;

import java.util.List;

import org.apache.commons.math3.exception.DimensionMismatchException;
import org.apache.commons.math3.exception.MathIllegalArgumentException;
import org.apache.commons.math3.exception.NumberIsTooLargeException;
import org.junit.Assert;
import org.junit.Test;

public class NPointCrossoverTest {

    @Test(expected = DimensionMismatchException.class)
    public void testCrossoverDimensionMismatchException() {
        final Integer[] p1 = new Integer[] {1,0,1,0,0,1,0,1,1};
        final Integer[] p2 = new Integer[] {0,1,1,0,1};

        final BinaryChromosome p1c = new DummyBinaryChromosome(p1);
        final BinaryChromosome p2c = new DummyBinaryChromosome(p2);

        final CrossoverPolicy cp = new NPointCrossover<Integer>(1);
        cp.crossover(p1c,p2c);
    }

    @Test(expected = NumberIsTooLargeException.class)
    public void testNumberIsTooLargeException() {
        final Integer[] p1 = new Integer[] {1,0,1,0,0,1,0,1,1};
        final Integer[] p2 = new Integer[] {0,1,1,0,1,0,1,1,1};

        final BinaryChromosome p1c = new DummyBinaryChromosome(p1);
        final BinaryChromosome p2c = new DummyBinaryChromosome(p2);

        final CrossoverPolicy cp = new NPointCrossover<Integer>(15);
        cp.crossover(p1c,p2c);
    }

    @Test(expected = MathIllegalArgumentException.class)
    public void testCrossoverInvalidFixedLengthChromosomeFirst() {
        final Integer[] p1 = new Integer[] {1,0,1,0,0,1,0,1,1};
        final BinaryChromosome p1c = new DummyBinaryChromosome(p1);
        final Chromosome p2c = new Chromosome() {
            public double fitness() {
                // Not important
                return 0;
            }
        };

        final CrossoverPolicy cp = new NPointCrossover<Integer>(1);
        cp.crossover(p1c,p2c);
    }

    @Test(expected = MathIllegalArgumentException.class)
    public void testCrossoverInvalidFixedLengthChromosomeSecond() {
        final Integer[] p1 = new Integer[] {1,0,1,0,0,1,0,1,1};
        final BinaryChromosome p2c = new DummyBinaryChromosome(p1);
        final Chromosome p1c = new Chromosome() {
            public double fitness() {
                // Not important
                return 0;
            }
        };

        final CrossoverPolicy cp = new NPointCrossover<Integer>(1);
        cp.crossover(p1c,p2c);
    }

    @Test
    public void testCrossover() {
        Integer[] p1 = new Integer[] {1,0,1,0,1,0,1,0,1};
        Integer[] p2 = new Integer[] {0,1,0,1,0,1,0,1,0};

        BinaryChromosome p1c = new DummyBinaryChromosome(p1);
        BinaryChromosome p2c = new DummyBinaryChromosome(p2);

        final int order = 3;
        NPointCrossover<Integer> npc = new NPointCrossover(order);

        // the two parent chromosomes are different at each position, so it is easy to detect
        // the number of crossovers that happened for each child
        for (int i=0; i<20; i++) {
            ChromosomePair pair = npc.crossover(p1c,p2c);

            Integer[] c1 = new Integer[p1.length];
            Integer[] c2 = new Integer[p2.length];

            c1 = ((BinaryChromosome) pair.getFirst()).getRepresentation().toArray(c1);
            c2 = ((BinaryChromosome) pair.getSecond()).getRepresentation().toArray(c2);

            Assert.assertEquals(order, detectCrossoverPoints(p1c, p2c, (BinaryChromosome) pair.getFirst()));
            Assert.assertEquals(order, detectCrossoverPoints(p2c, p1c, (BinaryChromosome) pair.getSecond()));
        }
    }

    private int detectCrossoverPoints(BinaryChromosome p1, BinaryChromosome p2, BinaryChromosome c) {
        int crossovers = 0;
        final int length = p1.getLength();

        final List<Integer> p1Rep = p1.getRepresentation();
        final List<Integer> p2Rep = p2.getRepresentation();
        final List<Integer> cRep = c.getRepresentation();

        List<Integer> rep = p1Rep;
        for (int i = 0; i < length; i++) {
            if (rep.get(i) != cRep.get(i)) {
                crossovers++;
                rep = rep == p1Rep ? p2Rep : p1Rep;
            }
        }

        return crossovers;
    }

}

Other Java examples (source code examples)

Here is a short list of links related to this Java NPointCrossoverTest.java source code file:



my book on functional programming

 

new blog posts

 

Copyright 1998-2019 Alvin Alexander, alvinalexander.com
All Rights Reserved.

A percentage of advertising revenue from
pages under the /java/jwarehouse URI on this website is
paid back to open source projects.