MOEAFramework-2.11.src.org.moeaframework.problem.BBOB2016.TransformVariablesOscillate Maven / Gradle / Ivy
/* 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 .
*/
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
* 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.
*/
/**
* Transformation that applies a monotone oscillation to the decision variables
* of the inner function.
*/
public class TransformVariablesOscillate extends BBOBTransformation {
/**
* Factor controlling the periodicity of the oscillation.
*/
public static final double ALPHA = 0.1;
/**
* Constructs a new transformation that applies an oscillation to the
* decision variables.
*
* @param function the inner function
*/
public TransformVariablesOscillate(BBOBFunction function) {
super(function);
}
@Override
public void evaluate(Solution solution) {
double[] x = EncodingUtils.getReal(solution);
double[] tx = x.clone();
for (int i = 0; i < x.length; i++) {
if (x[i] > 0.0) {
double tmp = Math.log(x[i]) / ALPHA;
double base = Math.exp(tmp + 0.49*(Math.sin(tmp) + Math.sin(0.79*tmp)));
tx[i] = Math.pow(base, ALPHA);
} else if (x[i] < 0.0) {
double tmp = Math.log(-x[i]) / ALPHA;
double base = Math.exp(tmp + 0.49*(Math.sin(0.55*tmp) + Math.sin(0.31*tmp)));
tx[i] = -Math.pow(base, ALPHA);
} else {
tx[i] = 0.0;
}
}
EncodingUtils.setReal(solution, tx);
function.evaluate(solution);
EncodingUtils.setReal(solution, x);
}
}