org.uma.jmetal.util.front.imp

Class FrontUtils

java.lang.Object

org.uma.jmetal.util.front.imp.FrontUtils

public class FrontUtils
extends Object

A Front is a list of points. This class includes utilities to work with fronts.

Version:

1.0

Author:

Antonio J. Nebro

Constructor Summary

Constructors

Constructor and Description
FrontUtils()

Method Summary

Modifier and Type	Method and Description
static double[][]	convertFrontToArray(Front front) Given a front, converts it to an array of double values
static List<PointSolution>	convertFrontToSolutionList(Front front) Given a front, converts it to a Solution set of PointSolutions
static double	distanceToClosestPoint(Point point, Front front) Gets the distance between a point and the nearest one in a given front
static double	distanceToNearestPoint(Point point, Front front) Gets the distance between a point and the nearest one in a front.
static Front	getInvertedFront(Front front) This method receives a normalized pareto front and return the inverted one.
static double[]	getMaximumValues(Front front) Gets the maximum values for each objectives in a front
static double[]	getMinimumValues(Front front) Gets the minimum values for each objectives in a given front
static Front	getNormalizedFront(Front front, double[] maximumValues, double[] minimumValues) This method receives a front and two points, one with maximum values and the other one with minimum, and returns a normalized front.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

FrontUtils

public FrontUtils()

Method Detail

getMaximumValues

public static double[] getMaximumValues(Front front)

Gets the maximum values for each objectives in a front

Parameters:

front - A front of objective values

Returns:

double [] An array with the maximum values for each objective

getMinimumValues

public static double[] getMinimumValues(Front front)

Gets the minimum values for each objectives in a given front

Parameters:

front - The front

Returns:

double [] An array of noOjectives values whit the minimum values for each objective

getNormalizedFront

public static Front getNormalizedFront(Front front,
                                       double[] maximumValues,
                                       double[] minimumValues)

This method receives a front and two points, one with maximum values and the other one with minimum, and returns a normalized front.

Parameters:

front - A front of points.

maximumValues - The maximum values allowed

minimumValues - The minimum values allowed

Returns:

the normalized front

distanceToNearestPoint

public static double distanceToNearestPoint(Point point,
                                            Front front)

Gets the distance between a point and the nearest one in a front. If a distance equals to 0 is found, that means that the point is in the front, so it is excluded

Parameters:

point - The point

front - The front that contains the other points to calculate the distances

Returns:

The minimum distance between the point and the front

distanceToClosestPoint

public static double distanceToClosestPoint(Point point,
                                            Front front)

Gets the distance between a point and the nearest one in a given front

Parameters:

point - The point

front - The front that contains the other points to calculate the distances

Returns:

The minimum distance between the point and the front

getInvertedFront

public static Front getInvertedFront(Front front)

This method receives a normalized pareto front and return the inverted one. This method is for minimization problems

Parameters:

front - The pareto front to inverse

Returns:

The inverted pareto front

convertFrontToArray

public static double[][] convertFrontToArray(Front front)

Given a front, converts it to an array of double values

Parameters:

front -

Returns:

A front as double[][] array

convertFrontToSolutionList

public static List<PointSolution> convertFrontToSolutionList(Front front)

Given a front, converts it to a Solution set of PointSolutions

Parameters:

front -

Returns:

A front as a List