Package org.opt4j.core.common.archive

Provides different implementations for the Archive.

See:
Description

Interface Summary

FrontDensityIndicator

The FrontDensityIndicator is an interface for the determination of density values of a front of Individuals.

Class Summary

AbstractArchive	This AbstractArchive provides some common methods for Archive s.
AdaptiveGridArchive	The AdaptiveGridArchive uses an adaptive grid in order to bound the size of the Archive, see "Properties of an Adaptive Archiving Algorithm for Storing Nondominated Vectors, J.
AdaptiveGridArchive.Cell	A single AdaptiveGridArchive.Cell of the grid.
ArchiveModule	The ArchiveModule determines an implementation for the Archive interface.
BoundedArchive	An Archive with bounded size.
Crowding	The Crowding, see "A fast and elitist multiobjective genetic algorithm : NSGA-II, K.
CrowdingArchive	The CrowdingArchive is based on the Crowding distance.
DefaultArchive	The DefaultArchive is the CrowdingArchive with a capacity of 100.
PopulationArchive	The PopulationArchive keeps the non-dominated Individuals from the Population.
UnboundedArchive	The UnboundedArchive is an Archive with unbounded size.

Enum Summary

ArchiveModule.Type

Archive type.

Package org.opt4j.core.common.archive Description

Provides different implementations for the Archive.

Abstract classes

The AbstractArchive provides common methods for archives to assure that no Pareto-dominated individual remains in the archive. It should be used for all implementations of Archive.

The BoundedArchive is an abstract class which provides common methods for bound archives, i.e. archives that have a specified maximum size. Such archives need to decide which non-dominated individuals should be dropped if the maximum size is reached.

Implementations

The UnboundedArchive stores each found Individual as long as it is not dominated. Especially for high dimensional and continuous problems, the number of non-dominated individuals can get very high.

The CrowdingArchive uses the crowding distance of NSGA2 to decide which Individuals to drop if the maximum size is reached.

The AdaptiveGridArchive uses an adaptive grid to decide which Individuals to drop.

The PopulationArchive just mirrors the non-dominated Individuals of the current population. Compared to the bounded archives above, it should only be used for the development or comparison of optimization algorithms.

The DefaultArchive defines the implementation to use if no archive is specified using the ArchiveModule. The default is the CrowdingArchive with a maximum size of 100 Individuals.

Modules

The ArchiveModule allows to select the implementation for the Archive.