double fitnessFunction(Solution individual, double[] lambda) {
double fitness;
fitness = 0.0;
if (functionType_.equals("_TCHE1")) {
double maxFun = -1.0e+30;
for (int n = 0; n < problem_.getNumberOfObjectives(); n++) {
double diff = Math.abs(individual.getObjective(n) - z_[n]);
double feval;
if (lambda[n] == 0) {
feval = 0.0001 * diff;
} else {
feval = diff * lambda[n];
}
if (feval > maxFun) {
maxFun = feval;
}
} // for
fitness = maxFun;
} // if
else if (functionType_.equals("_AGG")) {
double sum = 0.0;
for (int n = 0; n < problem_.getNumberOfObjectives(); n++) {
sum += (lambda[n]) * individual.getObjective(n);
}
fitness = sum;
} else if (functionType_.equals("_PBI")) {
double d1, d2, nl;
double theta = 5.0;
d1 = d2 = nl = 0.0;
for (int i = 0; i < problem_.getNumberOfObjectives(); i++) {
d1 += (individual.getObjective(i) - z_[i]) * lambda[i];
nl += Math.pow(lambda[i], 2.0);
}
nl = Math.sqrt(nl);
d1 = Math.abs(d1) / nl;
for (int i = 0; i < problem_.getNumberOfObjectives(); i++) {
d2 += Math.pow((individual.getObjective(i) - z_[i]) - d1 * (lambda[i] / nl), 2.0);
}
d2 = Math.sqrt(d2);
fitness = (d1 + theta * d2);
} else {
System.out.println("MOEAD.fitnessFunction: unknown type " + functionType_);
System.exit(-1);
}
return fitness;
} // fitnessEvaluation
/**
* Evaluates a solution
*
* @param solution The solution to evaluate
* @throws JMException
*/
public void evaluate(Solution solution) throws JMException {
DecisionVariables decisionVariables = solution.getDecisionVariables();
double[] x = new double[numberOfVariables_];
double[] fx = new double[numberOfVariables_];
double g;
double h;
double sum;
for (int i = 0; i < numberOfVariables_; i++) x[i] = decisionVariables.variables_[i].getValue();
fx[0] = x[0];
sum = 0.0;
for (int i = 1; i < numberOfVariables_; i++) sum += (x[i] * x[i] - x[0]) * (x[i] * x[i] - x[0]);
g = 1.0 + 9.0 * sum / (numberOfVariables_ - 1.0);
h = 1.0 - Math.sqrt(x[0] / g);
fx[1] = g * h;
solution.setObjective(0, fx[0]);
solution.setObjective(1, fx[1]);
} // evaluate
/**
* Evaluates a solution.
*
* @param solution The solution to evaluate.
* @throws JMException
*/
public void evaluate(Solution solution) throws JMException {
Variable[] decisionVariables = solution.getDecisionVariables();
double[] x = new double[numberOfVariables_];
for (int i = 0; i < numberOfVariables_; i++) x[i] = decisionVariables[i].getValue();
int count1, count2, count3;
double sum1, sum2, sum3, yj, hj;
sum1 = sum2 = sum3 = 0.0;
count1 = count2 = count3 = 0;
for (int j = 3; j <= numberOfVariables_; j++) {
yj =
x[j - 1] - 2.0 * x[1] * Math.sin(2.0 * Math.PI * x[0] + j * Math.PI / numberOfVariables_);
hj = 4.0 * yj * yj - Math.cos(8.0 * Math.PI * yj) + 1.0;
if (j % 3 == 1) {
sum1 += hj;
count1++;
} else if (j % 3 == 2) {
sum2 += hj;
count2++;
} else {
sum3 += hj;
count3++;
}
}
solution.setObjective(
0,
Math.cos(0.5 * Math.PI * x[0]) * Math.cos(0.5 * Math.PI * x[1])
+ 2.0 * sum1 / (double) count1);
solution.setObjective(
1,
Math.cos(0.5 * Math.PI * x[0]) * Math.sin(0.5 * Math.PI * x[1])
+ 2.0 * sum2 / (double) count2);
solution.setObjective(2, Math.sin(0.5 * Math.PI * x[0]) + 2.0 * sum3 / (double) count3);
} // evaluate