/* Copyright 2009-2016 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.BBOB2016;
import org.moeaframework.core.Solution;
import org.moeaframework.core.variable.EncodingUtils;
/*
* The following source code is derived from the Coco Framework available at
* <https://github.com/numbbo/coco> under the 3-clause BSD license. The
* original code is copyright 2013 by the NumBBO/CoCO team. See the AUTHORS
* file located in the Coco Framework repository for more details.
*/
/**
* The z-hat transformation used by the Schwefel function.
*/
public class TransformVariablesZHat extends BBOBTransformation {
/**
* The location of the optimum.
*/
private final double[] xopt;
/**
* Constructs a new instance of the z-hat transformation.
*
* @param function the inner function
* @param xopt the location of the optimum
*/
public TransformVariablesZHat(BBOBFunction function, double[] xopt) {
super(function);
this.xopt = xopt;
}
@Override
public void evaluate(Solution solution) {
double[] x = EncodingUtils.getReal(solution);
double[] tx = x.clone();
tx[0] = x[0];
for (int i = 1; i < x.length; i++) {
tx[i] = x[i] + 0.25 * (x[i-1] - 2.0 * Math.abs(xopt[i-1]));
}
EncodingUtils.setReal(solution, tx);
function.evaluate(solution);
EncodingUtils.setReal(solution, x);
}
}