net.sourceforge.cilib.pso.dynamic.detectionstrategies
Class RandomSentryPointsDetectionStrategy<E extends PopulationBasedAlgorithm>

java.lang.Object
  net.sourceforge.cilib.pso.dynamic.detectionstrategies.EnvironmentChangeDetectionStrategy<E>
      net.sourceforge.cilib.pso.dynamic.detectionstrategies.RandomSentriesDetectionStrategy<E>
          net.sourceforge.cilib.pso.dynamic.detectionstrategies.RandomSentryPointsDetectionStrategy<E>

Type Parameters:

E - some population based algorithm

All Implemented Interfaces:

Serializable, Cloneable

public class RandomSentryPointsDetectionStrategy<E extends PopulationBasedAlgorithm>
extends RandomSentriesDetectionStrategy<E>

This class defines a detection strategy that uses a user-specified number of sentry points and an value to detect whether a change has occured in the environment within a number of consecutive iterations.

Author:

Theuns Cloete

See Also:

Serialized Form

Field Summary

protected ArrayList<Entity>

sentries

Fields inherited from class net.sourceforge.cilib.pso.dynamic.detectionstrategies.RandomSentriesDetectionStrategy

numberOfSentries, randomGenerator

Fields inherited from class net.sourceforge.cilib.pso.dynamic.detectionstrategies.EnvironmentChangeDetectionStrategy

epsilon, interval

Constructor Summary

RandomSentryPointsDetectionStrategy()

RandomSentryPointsDetectionStrategy(RandomSentryPointsDetectionStrategy<E> rhs)

Method Summary

boolean	detect(PopulationBasedAlgorithm algorithm) After every EnvironmentChangeDetectionStrategy.interval iterations, iterate through all sentry points and compare their previous fitness values with their current fitness values.
RandomSentryPointsDetectionStrategy<E>	getClone() Clone the EnvironmentChangeDetectionStrategy object.

Methods inherited from class net.sourceforge.cilib.pso.dynamic.detectionstrategies.RandomSentriesDetectionStrategy

getNumberOfSentries, getRandomNumberGenerator, setNumberOfSentries, setRandomNumberGenerator

Methods inherited from class net.sourceforge.cilib.pso.dynamic.detectionstrategies.EnvironmentChangeDetectionStrategy

getEpsilon, getIterationsModulus, setEpsilon, setIterationsModulus

Methods inherited from class java.lang.Object

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

Field Detail

sentries

protected ArrayList<Entity> sentries

Constructor Detail

RandomSentryPointsDetectionStrategy

public RandomSentryPointsDetectionStrategy()

RandomSentryPointsDetectionStrategy

public RandomSentryPointsDetectionStrategy(RandomSentryPointsDetectionStrategy<E> rhs)

Method Detail

getClone

public RandomSentryPointsDetectionStrategy<E> getClone()

Description copied from class: EnvironmentChangeDetectionStrategy

Clone the EnvironmentChangeDetectionStrategy object.

Specified by:

getClone in interface Cloneable

Overrides:

getClone in class RandomSentriesDetectionStrategy<E extends PopulationBasedAlgorithm>

Returns:

A cloned EnvironmentChangeDetectionStrategy

See Also:

Object.clone()

detect

public boolean detect(PopulationBasedAlgorithm algorithm)

After every EnvironmentChangeDetectionStrategy.interval iterations, iterate through all sentry points and compare their previous fitness values with their current fitness values. An environment change is detected when the difference between the previous and current fitness values are >= the specified EnvironmentChangeDetectionStrategy.epsilon value. Although this detection strategy only makes use of random sentry points, the entities in the population based algorithm are sent through to the {@link #initializeSentryPoints(Topology) method to initialize the sentry points.

Overrides:

detect in class RandomSentriesDetectionStrategy<E extends PopulationBasedAlgorithm>

Parameters:

algorithm - used to get hold of topology of entities and number of iterations

Returns:

true if a change has been detected, false otherwise