/** * Write report on eveluation to the given stream. * * @param a_fitnessFunction p_SupergeneChangeFitnessFunction * @param a_population Genotype * @return Chromosome */ public IChromosome report( SupergeneChangeFitnessFunction a_fitnessFunction, Genotype a_population) { IChromosome bestSolutionSoFar = a_population.getFittestChromosome(); if (!REPORT_ENABLED) { return bestSolutionSoFar; } System.out.println( "\nThe best solution has a fitness value of " + bestSolutionSoFar.getFitnessValue()); System.out.println("It contained the following: "); System.out.println( "\t" + a_fitnessFunction.getNumberOfCoinsAtGene(bestSolutionSoFar, QUARTERS) + " quarters."); System.out.println( "\t" + a_fitnessFunction.getNumberOfCoinsAtGene(bestSolutionSoFar, DIMES) + " dimes."); System.out.println( "\t" + a_fitnessFunction.getNumberOfCoinsAtGene(bestSolutionSoFar, NICKELS) + " nickels."); System.out.println( "\t" + a_fitnessFunction.getNumberOfCoinsAtGene(bestSolutionSoFar, PENNIES) + " pennies."); System.out.println( "For a total of " + a_fitnessFunction.amountOfChange(bestSolutionSoFar) + " cents in " + a_fitnessFunction.getTotalNumberOfCoins(bestSolutionSoFar) + " coins."); return bestSolutionSoFar; }
/** * Find and print the solution, return the solution error. * * @param a_conf the configuration to use * @return absolute difference between the required and computed change */ protected int solve( Configuration a_conf, int a_targetChangeAmount, SupergeneChangeFitnessFunction a_fitnessFunction, Gene[] a_sampleGenes) throws InvalidConfigurationException { IChromosome sampleChromosome = new Chromosome(a_conf, a_sampleGenes); a_conf.setSampleChromosome(sampleChromosome); // Finally, we need to tell the Configuration object how many // Chromosomes we want in our population. The more Chromosomes, // the larger number of potential solutions (which is good for // finding the answer), but the longer it will take to evolve // the population (which could be seen as bad). We'll just set // the population size to 500 here. // ------------------------------------------------------------ a_conf.setPopulationSize(POPULATION_SIZE); // Create random initial population of Chromosomes. // ------------------------------------------------ Genotype population = Genotype.randomInitialGenotype(a_conf); int s; Evolution: // Evolve the population, break if the the change solution is found. // ----------------------------------------------------------------- for (int i = 0; i < MAX_ALLOWED_EVOLUTIONS; i++) { population.evolve(); s = Math.abs( a_fitnessFunction.amountOfChange(population.getFittestChromosome()) - a_targetChangeAmount); if (s == 0) { break Evolution; } } // Display the best solution we found. // ----------------------------------- IChromosome bestSolutionSoFar = report(a_fitnessFunction, population); return Math.abs(a_fitnessFunction.amountOfChange(bestSolutionSoFar) - a_targetChangeAmount); }