fitnessalgorithmf5.java

使用java编写的关于通讯及串口编程所必需的类库

/*
 * FitnessAlgorithmF5.java
 *
 * Created on March 10, 2003, 2:04 PM
 */

package com.adaptiveview.ospso.test;

import com.adaptiveview.ospso.*;
import com.adaptiveview.ospso.dmi.*;

/**Shaffer's test function "f6" --
 *<code>Fitness = 0.0 - abs(0.5 - ((sin(sqrt(x^2 + y^2))^2 - 0.5)/((1.0 + 0.001*(x^2 + y^2))^2));
 * Dimension Boundaries = [-25.0..25.0];
 * Boundary Type = Constraint.BOUNCE.</code>
 *
 * @author  AdaptiveView.com
 */
public class FitnessAlgorithmF5 implements IFitnessAlgorithm, DMI_AboutFitnessAlgorithms {
    
    private int dimensions;
    private Constraint dimensionConstraint;
    private String problemDescription;
    private String boundaryTypeName;
    
    /** Creates a new instance of FitnessAlgorithm1 */
    public FitnessAlgorithmF5() {
        // Set the following according to problem in calculateFitness()
        dimensions = 2; 
        dimensionConstraint = new Constraint(-100.0,100.0,Constraint.BOUNCE);
        boundaryTypeName = "BOUNCE";
        problemDescription = "Shaffer's f6: 0.5 + ((sin(sqrt(x^2 + y^2))^2 - 0.5)/((1.0 + 0.001*(x^2 + y^2))^2) = 0.0";
    }
    
    public double calculateFitness(LocationChange location) {
        double[] c = location.getCopyOfCoordinates();
        double answer = 0.0;

       /* Problem:      0.5 + ((sin(sqrt(x^2 + y^2))^2 - 0.5)/((1.0 + 0.001*(x^2 + y^2))^2)
        * Data sources: x = c[0]; y = c[1]; 
        */
        double x2y2 = c[0]*c[0]+c[1]*c[1];
        double n = Math.pow(Math.sin(Math.sqrt(x2y2)),2.0) - 0.5;
        double d = Math.pow((1.0 + 0.001*x2y2),2.0);
        answer = 0.5 + (n / d);

        return convertToFitness(answer);
    }
    
    private double convertToFitness(double answer) {
        return 0.0 - Math.abs(answer);
    }
 
    /** Returns the number of dimesnions (unknowns) in the solution space.
     * @return the number of dimesnions
     */
    public int getDimensions() {
        return dimensions;
    }
    
    /** Returns a reference to the dimension Constraint instance.
     * @return the dimension Constraint
     */
    public Constraint getDimensionConstraint() {
        return dimensionConstraint;
    }
    
    /** Returns a description of the solution space.
     * @return a String describing the solution space.
     */
    public String toString() {
        StringBuffer s = new StringBuffer();
        s.append(problemDescription);
        s.append(" (Dimensions=");
        s.append(dimensions);
        s.append("; Dimension[Minimum=");
        s.append(dimensionConstraint.getMinimum());
        s.append(", Maximum=");
        s.append(dimensionConstraint.getMaximum());
        s.append(", BoundaryType='");
        s.append(boundaryTypeName);
        s.append("'])");
        return s.toString();
    }
}