pl.edu.agh.age.compute.labs.improvement

Class LabsCrossStepSawSearch

java.lang.Object

pl.edu.agh.age.compute.labs.improvement.AbstractLabsImprovement

pl.edu.agh.age.compute.labs.improvement.AbstractLabsSawSearch

pl.edu.agh.age.compute.labs.improvement.LabsCrossStepSawSearch

All Implemented Interfaces:

Improvement<LabsSolution>

public final class LabsCrossStepSawSearch
extends AbstractLabsSawSearch

This is a variant of SelfAvoidingWalk improvement operator for LABS problem, which uses a single walkList shared with all agents in the population. Each iteration adds an entry to the list, which can influence improvement computation for future agents, by eliminating repetitions of already processed solutions.

The implementation uses a limited size cache mechanism with entry eviction. Thus, it has a high memory usage. For LABS of length 201, a single cache entry takes around 1000 bytes of memory. If you intent to use this improvement operator in AgE computation, make sure that cacheSize is set to the value that will not cause exceeding current Java maximum heapsize value.

Field Summary

Fields

Modifier and Type	Field and Description
private Cache<java.util.List<java.lang.Boolean>,java.lang.Double>	walkList

Fields inherited from class pl.edu.agh.age.compute.labs.improvement.AbstractLabsImprovement

evaluator

Constructor Summary

Constructors

Constructor and Description
LabsCrossStepSawSearch(LabsEvaluator evaluator, int iterations, long cacheSize, boolean useFastFlipAlgorithm)

Method Summary

Modifier and Type	Method and Description
protected void	addToWalkList(LabsSolution solution)
protected void	clearWalkList()
protected boolean	isInWalkList(LabsSolution solution)

Methods inherited from class pl.edu.agh.age.compute.labs.improvement.AbstractLabsSawSearch

improve

Methods inherited from class pl.edu.agh.age.compute.labs.improvement.AbstractLabsImprovement

getFlippedSolution

Methods inherited from class java.lang.Object

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

Field Detail

walkList

private final Cache<java.util.List<java.lang.Boolean>,java.lang.Double> walkList

Constructor Detail

LabsCrossStepSawSearch

public LabsCrossStepSawSearch(LabsEvaluator evaluator,
                              int iterations,
                              long cacheSize,
                              boolean useFastFlipAlgorithm)

Method Detail

clearWalkList

protected void clearWalkList()

Specified by:

clearWalkList in class AbstractLabsSawSearch

addToWalkList

protected void addToWalkList(LabsSolution solution)

Specified by:

addToWalkList in class AbstractLabsSawSearch

isInWalkList

protected boolean isInWalkList(LabsSolution solution)

Specified by:

isInWalkList in class AbstractLabsSawSearch