| /* |
| * 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.ignite.examples.ml.genetic.change; |
| |
| import java.util.List; |
| import org.apache.ignite.ml.genetic.Gene; |
| import org.apache.ignite.ml.genetic.IFitnessFunction; |
| |
| /** |
| * This example demonstrates how to create a {@link IFitnessFunction}. |
| * <p> |
| * Your fitness function will vary depending on your particular use case. For this fitness function, we simply want to |
| * calculate the value of an individual solution relative to other solutions.</p> |
| */ |
| public class OptimizeMakeChangeFitnessFunction implements IFitnessFunction { |
| /** |
| * Target amount. |
| */ |
| private int targetAmount; |
| |
| /** |
| * @param targetAmount Amount of change. |
| */ |
| public OptimizeMakeChangeFitnessFunction(int targetAmount) { |
| this.targetAmount = targetAmount; |
| } |
| |
| /** |
| * {@inheritDoc} |
| */ |
| @Override public double evaluate(List<Gene> genes) { |
| int changeAmount = getAmountOfChange(genes); |
| int totalCoins = getTotalNumberOfCoins(genes); |
| int changeDifference = Math.abs(targetAmount - changeAmount); |
| |
| double fitness = (99 - changeDifference); |
| |
| if (changeAmount == targetAmount) |
| fitness += 100 - (10 * totalCoins); |
| |
| return fitness; |
| } |
| |
| /** |
| * Calculate amount of change. |
| * |
| * @param genes List of genes. |
| * @return Amount of change. |
| */ |
| private int getAmountOfChange(List<Gene> genes) { |
| Gene quarterGene = genes.get(0); |
| Gene dimeGene = genes.get(1); |
| Gene nickelGene = genes.get(2); |
| Gene pennyGene = genes.get(3); |
| |
| int numQuarters = ((Coin)quarterGene.getVal()).getNumOfCoins(); |
| int numDimes = ((Coin)dimeGene.getVal()).getNumOfCoins(); |
| int numNickels = ((Coin)nickelGene.getVal()).getNumOfCoins(); |
| int numPennies = ((Coin)pennyGene.getVal()).getNumOfCoins(); |
| |
| return (numQuarters * 25) + (numDimes * 10) + (numNickels * 5) + numPennies; |
| } |
| |
| /** |
| * Return the total number of coins. |
| * |
| * @param genes List of genes. |
| * @return Number of coins. |
| */ |
| private int getTotalNumberOfCoins(List<Gene> genes) { |
| int totalNumOfCoins = 0; |
| |
| for (Gene gene : genes) { |
| int numOfCoins = ((Coin)gene.getVal()).getNumOfCoins(); |
| totalNumOfCoins += numOfCoins; |
| } |
| |
| return totalNumOfCoins; |
| } |
| } |