List of usage examples for org.apache.commons.math3.genetics Population getPopulationLimit
int getPopulationLimit();
From source file:eu.tsp.sal.SensorGeneticAlgorithm.java
/** * Evolve the given population into the next generation. * <p>//from w ww . j a v a2s. c o m * <ol> * <li>Get nextGeneration population to fill from <code>current</code> * generation, using its nextGeneration method</li> * <li>Loop until new generation is filled:</li> * <ul><li>Apply configured SelectionPolicy to select a pair of parents * from <code>current</code></li> * <li>With probability = {@link #getCrossoverRate()}, apply * configured {@link CrossoverPolicy} to parents</li> * <li>With probability = {@link #getMutationRate()}, apply * configured {@link MutationPolicy} to each of the offspring</li> * <li>Add offspring individually to nextGeneration, * space permitting</li> * </ul> * <li>Return nextGeneration</li> * </ol> * * @param current the current population. * @return the population for the next generation. */ public Population nextGeneration(final Population current) { Population nextGeneration = current.nextGeneration(); RandomGenerator randGen = getRandomGenerator(); while (nextGeneration.getPopulationSize() < nextGeneration.getPopulationLimit()) { // select parent chromosomes ChromosomePair pair = getSelectionPolicy().select(current); //System.out.println("*****" + pair); // crossover? if (randGen.nextDouble() < getCrossoverRate()) { // apply crossover policy to create two offspring pair = getCrossoverPolicy().crossover(pair.getFirst(), pair.getSecond()); } // mutation? if (randGen.nextDouble() < getMutationRate()) { // apply mutation policy to the chromosomes pair = new ChromosomePair(getMutationPolicy().mutate(pair.getFirst()), getMutationPolicy().mutate(pair.getSecond())); } // add the first chromosome to the population nextGeneration.addChromosome(pair.getFirst()); // is there still a place for the second chromosome? if (nextGeneration.getPopulationSize() < nextGeneration.getPopulationLimit()) { // add the second chromosome to the population nextGeneration.addChromosome(pair.getSecond()); } } System.out.println("\nGeneration (iteration): " + (generationsEvolved + 1)); WSN.printPopulation(nextGeneration); return nextGeneration; }