jmetal.util.archive
Class R2Archive

java.lang.Object
  jmetal.core.SolutionSet
      jmetal.util.archive.Archive
          jmetal.util.archive.R2Archive

All Implemented Interfaces:

java.io.Serializable

public class R2Archive
extends Archive

This class implements a bounded archive based on crowding distances (as defined in NSGA-II).

See Also:

Serialized Form

Field Summary

Fields inherited from class jmetal.core.SolutionSet

solutionsList_

Constructor Summary

R2Archive(int maxSize)
Constructor.

R2Archive(int maxSize, int numberOfObjectives, java.lang.String file)
Constructor.

Method Summary

boolean	add(Solution solution) Adds a Solution to the archive.
Solution	getSolution() Returns a solution from the archive based on their contribution to the R2 indicator.

Methods inherited from class jmetal.core.SolutionSet

add, best, clear, get, getCapacity, getMaxSize, indexWorst, iterator, printFeasibleFUN, printFeasibleVAR, printObjectives, printObjectivesToFile, printVariablesToFile, remove, replace, setCapacity, size, sort, union, worst, writeObjectivesToMatrix

Methods inherited from class java.lang.Object

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

Constructor Detail

R2Archive

public R2Archive(int maxSize)

Constructor. Creates an R2Archive for a problem of 2 objectives

Parameters:

maxSize - The maximum size of the archive.

R2Archive

public R2Archive(int maxSize,
                 int numberOfObjectives,
                 java.lang.String file)

Constructor.

Parameters:

maxSize - The maximum size of the archive.

numberOfObjectives - The number of objectives.

Method Detail

add

public boolean add(Solution solution)

Adds a Solution to the archive. If the Solution is dominated by any member of the archive, then it is discarded. If the Solution dominates some members of the archive, these are removed. If the archive is full and the Solution has to be inserted, the solutions are sorted by crowding distance and the one having the minimum crowding distance value.

Overrides:

add in class SolutionSet

Parameters:

solution - The Solution

Returns:

true if the Solution has been inserted, false otherwise.

getSolution

public Solution getSolution()

Returns a solution from the archive based on their contribution to the R2 indicator. The solution is chosen using a binary tournament.