01 /*
02 * JENES
03 * A time asnd memory efficient Java library for genetic algorithms and more
04 * Copyright (C) 2011 Intelligentia srl
05 *
06 * This program is free software: you can redistribute it and/or modify
07 * it under the terms of the GNU General Public License as published by
08 * the Free Software Foundation, either version 3 of the License, or
09 * (at your option) any later version.
10 *
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public License
17 * along with this program. If not, see <http://www.gnu.org/licenses/>.
18 */
19 package jenes.tutorials.old.problem2;
20
21 import jenes.GeneticAlgorithm;
22 import jenes.chromosome.IntegerChromosome;
23 import jenes.population.Individual;
24 import jenes.population.Population;
25
26 /**
27 * Tutorial showing how to extend <code>GeneticAlgorithm</code> and how to use
28 * the flexible and configurable breeding structure in Jenes.
29 * The problem consists in searching a pattern of integers with a given precision.
30 * Solutions flow through two different crossovers in parallel. Some are processed by
31 * a single point crossover, the other by a double point crossover.
32 * After solutions are mutated.
33 *
34 * This class implements the algorithm by extending <code>GeneticAlgorithm</code>.
35 *
36 * @author Luigi Troiano
37 * @author Pierpaolo Lombardi
38 *
39 * @version 1.0
40 *
41 * @since 1.0
42 */
43 public class PatternGA extends GeneticAlgorithm<IntegerChromosome>{
44
45 private int[] target;
46 private int precision;
47
48 public PatternGA(Population<IntegerChromosome> pop, int numGen) {
49 super(pop,numGen);
50 this.setBiggerIsBetter(false);
51 }
52
53 public void setTarget(int[] target) {
54 this.target = target;
55 }
56
57 public void setPrecision(int precision) {
58 this.precision = precision;
59 }
60
61 @Override
62 public void evaluateIndividual(Individual<IntegerChromosome> individual) {
63 IntegerChromosome chrom = individual.getChromosome();
64 int diff = 0;
65 int length=chrom.length();
66 for(int i=0;i<length;i++){
67 diff += Math.abs(chrom.getValue(i)-this.target[i]);
68 }
69 individual.setScore(diff);
70 }
71
72 @Override
73 protected boolean end(){
74 jenes.population.Population.Statistics stat = this.getCurrentPopulation().getStatistics();
75 return stat.getLegalLowestScore() <= this.precision;
76 }
77 }
|
|
|
