Package se.liu.ida.hefquin.engine.queryproc.impl.poptimizer.evolutionaryAlgorithm

Class TerminateByDiversityDistMax

java.lang.Object

se.liu.ida.hefquin.engine.queryproc.impl.poptimizer.evolutionaryAlgorithm.TerminationCriterionBase

se.liu.ida.hefquin.engine.queryproc.impl.poptimizer.evolutionaryAlgorithm.TerminateByDiversityDistMax

All Implemented Interfaces:

TerminationCriterion

public class TerminateByDiversityDistMax
extends TerminationCriterionBase

Diversity-based termination criterion: Termination is triggered when the relative difference between the cost of the best plan and the worst plan within each generation has not exceeded a specified distance threshold for a number of generations.

Field Summary

Fields

Modifier and Type	Field	Description
protected final double	distMaxThreshold

Fields inherited from class se.liu.ida.hefquin.engine.queryproc.impl.poptimizer.evolutionaryAlgorithm.TerminationCriterionBase

nrGenerations

Constructor Summary

Constructors

Constructor	Description
TerminateByDiversityDistMax(double distMaxThreshold, LogicalPlan plan)

Method Summary

Modifier and Type	Method	Description
static TerminationCriterionFactory	getFactory(double distMaxThreshold)
boolean	readyToTerminate(Generation currentGeneration, List<Generation> allPreviousGenerations)	Returns true if this termination criterion has been reached with the current generation.

Methods inherited from class se.liu.ida.hefquin.engine.queryproc.impl.poptimizer.evolutionaryAlgorithm.TerminationCriterionBase

calcFactorial, countNumOfOps

Methods inherited from class java.lang.Object

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

Field Details

distMaxThreshold

protected final double distMaxThreshold

Constructor Details

TerminateByDiversityDistMax

public TerminateByDiversityDistMax(double distMaxThreshold,
 LogicalPlan plan)

Method Details

getFactory

public static TerminationCriterionFactory getFactory(double distMaxThreshold)

readyToTerminate

public boolean readyToTerminate(Generation currentGeneration,
 List<Generation> allPreviousGenerations)

Description copied from interface: TerminationCriterion

Returns true if this termination criterion has been reached with the current generation.

Parameters:

currentGeneration - the current generation for which the termination criterion is test

allPreviousGenerations - a list of all previous generations, in the order in which they have been created