/* Copyright 2009-2015 David Hadka * * This file is part of the MOEA Framework. * * The MOEA Framework is free software: you can redistribute it and/or modify * it under the terms of the GNU Lesser General Public License as published by * the Free Software Foundation, either version 3 of the License, or (at your * option) any later version. * * The MOEA Framework is distributed in the hope that it will be useful, but * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public * License for more details. * * You should have received a copy of the GNU Lesser General Public License * along with the MOEA Framework. If not, see <http://www.gnu.org/licenses/>. */ package org.moeaframework.problem.misc; import org.moeaframework.core.Solution; import org.moeaframework.core.variable.RealVariable; import org.moeaframework.problem.AbstractProblem; /** * The Kita problem. * <p> * Properties: * <ul> * <li>Disconnected Pareto set * <li>Disconnected and concave Pareto front * <li>Constrained * <li>Maximization (objectives are negated) * </ul> * <p> * References: * <ol> * <li>Kita, H., et al. (1996). "Multi-Objective Optimization by Means of * the Thermodynamical Genetic Algorithm." Parallel Problem Solving from * Nature — PPSN IV, Lecture Notes in Computer Science, Springer, * pp. 504-512. * <li>Van Veldhuizen, D. A (1999). "Multiobjective Evolutionary Algorithms: * Classifications, Analyses, and New Innovations." Air Force Institute * of Technology, Ph.D. Thesis, Appendix B. * </ol> */ public class Kita extends AbstractProblem { /** * Constructs the Kita problem. */ public Kita() { super(2, 2, 3); } @Override public void evaluate(Solution solution) { double x = ((RealVariable)solution.getVariable(0)).getValue(); double y = ((RealVariable)solution.getVariable(1)).getValue(); double f1 = -Math.pow(x, 2.0) + y; double f2 = 0.5*x + y + 1.0; double c1 = 1.0/6.0*x + y - 13.0/2.0; double c2 = 0.5*x + y - 15.0/2.0; double c3 = 5.0*x + y - 30.0; solution.setObjective(0, -f1); solution.setObjective(1, -f2); solution.setConstraint(0, c1 <= 0.0 ? 0.0 : c1); solution.setConstraint(1, c2 <= 0.0 ? 0.0 : c2); solution.setConstraint(2, c3 <= 0.0 ? 0.0 : c3); } @Override public Solution newSolution() { Solution solution = new Solution(2, 2, 3); solution.setVariable(0, new RealVariable(0.0, 7.0)); solution.setVariable(1, new RealVariable(0.0, 7.0)); return solution; } }