org.moeaframework.core.operator.real
Class UM

java.lang.Object
  org.moeaframework.core.operator.real.UM

All Implemented Interfaces:

Variation

public class UM
extends Object
implements Variation

Uniform mutation (UM) operator. Each decision variable is mutated by selecting a new value within its bounds uniformly at random. The figure below depicts the offspring distribution.

It is recommended each decision variable is mutated with a probability of 1 / L, where L is the number of decision variables. This results in one mutation per offspring on average.

This operator is type-safe.

Constructor Summary

UM(double probability)
Constructs a uniform mutation operator.

Method Summary

static void	evolve(RealVariable variable) Mutates the specified variable using uniform mutation.
Solution[]	evolve(Solution[] parents) Evolves one or more parent solutions (specified by getArity) and produces one or more child solutions.
int	getArity() Returns the number of solutions that must be supplied to the evolve method.
double	getProbability() Returns the probability of mutating each variable in a solution.

Methods inherited from class java.lang.Object

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

Constructor Detail

UM

public UM(double probability)

Constructs a uniform mutation operator.

Parameters:

probability - the probability of mutating each variable in a solution

Method Detail

getProbability

public double getProbability()

Returns the probability of mutating each variable in a solution.

Returns:

the probability of mutating each variable in a solution

evolve

public Solution[] evolve(Solution[] parents)

Description copied from interface: Variation

Evolves one or more parent solutions (specified by getArity) and produces one or more child solutions. By contract, the parents must not be modified. The copy constructor should be used to create copies of the parents with these copies subsequently modified.

Specified by:

evolve in interface Variation

Parameters:

parents - the array of parent solutions

Returns:

an array of child solutions

evolve

public static void evolve(RealVariable variable)

Mutates the specified variable using uniform mutation.

Parameters:

variable - the variable to be mutated

getArity

public int getArity()

Description copied from interface: Variation

Returns the number of solutions that must be supplied to the evolve method.

Specified by:

getArity in interface Variation

Returns:

the number of solutions that must be supplied to the evolve method