net.sourceforge.cilib.entity.operators.selection
Class RouletteWheelSelectionStrategy

java.lang.Object
  net.sourceforge.cilib.entity.operators.selection.SelectionStrategy
      net.sourceforge.cilib.entity.operators.selection.RouletteWheelSelectionStrategy

All Implemented Interfaces:

Serializable, Operator, Cloneable

public class RouletteWheelSelectionStrategy
extends SelectionStrategy

This class implements Roulette Wheel selection, also known as proportionate selection. The probability of selecting an Entity is equal to the ratio of its fitness to the sum total of the fitness of all the Entitys in the population.

This method of selection is not particularly useful if a single solution has very high fitness as compared to the rest. This results in selecting the fittest solution every time we make a selection.

Author:

Vikash Ranjan Parida

See Also:

Serialized Form

Constructor Summary

RouletteWheelSelectionStrategy()
Create an instance of the RouletteWheelSelectionStrategy.

RouletteWheelSelectionStrategy(RouletteWheelSelectionStrategy copy)
Create a copy of the provided instance.

Method Summary

SelectionStrategy	getClone() Create a cloned copy of the current object and return it.
void	performOperation(TopologyHolder holder) Perform the operator operation given the current TopologyHolder.
<T extends Entity> T	select(Topology<T> population) Apply the selection strategy and return a single Entity.

Methods inherited from class java.lang.Object

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

Constructor Detail

RouletteWheelSelectionStrategy

public RouletteWheelSelectionStrategy()

Create an instance of the RouletteWheelSelectionStrategy.

RouletteWheelSelectionStrategy

public RouletteWheelSelectionStrategy(RouletteWheelSelectionStrategy copy)

Create a copy of the provided instance.

Parameters:

copy - The instance to copy.

Method Detail

getClone

public SelectionStrategy getClone()

Create a cloned copy of the current object and return it. In general the created copy will be a deep copy of the provided instance. As a result this operation an be quite expensive if used incorrectly.

Specified by:

getClone in interface Operator

Specified by:

getClone in interface Cloneable

Specified by:

getClone in class SelectionStrategy

Returns:

An exact clone of the current object instance.

See Also:

Object.clone()

select

public <T extends Entity> T select(Topology<T> population)

Apply the selection strategy and return a single Entity.

Specified by:

select in class SelectionStrategy

Type Parameters:

T - The Entity type.

Parameters:

population - The Topology to make the selection from.

Returns:

The selected Entity.

performOperation

public void performOperation(TopologyHolder holder)

Perform the operator operation given the current TopologyHolder.

Parameters:

holder - The TopologyHolder representing the required Topology instances.