Module io.jenetics.base

Package io.jenetics

Class SwapMutator<G extends Gene<?,G>,C extends Comparable<? super C>>

java.lang.Object

io.jenetics.AbstractAlterer<G,C>

io.jenetics.Mutator<G,C>

io.jenetics.SwapMutator<G,C>

All Implemented Interfaces:

Alterer<G,C>

public class SwapMutator<G extends Gene<?,G>,C extends Comparable<? super C>>
extends Mutator<G,C>

The SwapMutation changes the order of genes in a chromosome, with the hope of bringing related genes closer together, thereby facilitating the production of building blocks. This mutation operator can also be used for combinatorial problems, where no duplicated genes within a chromosome are allowed, e.g., for the TSP.

This mutator is also known as Partial Shuffle Mutator (PSM).

Since:

1.0

Version:

5.0

See Also:

• Analyzing the Performance of Mutation Operators to Solve the Travelling Salesman Problem

Field Summary

Fields inherited from class io.jenetics.AbstractAlterer

_probability

Fields inherited from interface io.jenetics.Alterer

DEFAULT_ALTER_PROBABILITY

Constructor Summary

Constructors

Constructor	Description
SwapMutator()	Default constructor, with default mutation probability (Alterer.DEFAULT_ALTER_PROBABILITY).
SwapMutator(double probability)	Constructs an alterer with a given recombination probability.

Method Summary

Modifier and Type	Method	Description
protected MutatorResult<Chromosome<G>>	mutate(Chromosome<G> chromosome, double p, RandomGenerator random)	Swaps the genes in the given array, with the mutation probability of this mutation.

Methods inherited from class io.jenetics.Mutator

alter, mutate, mutate, mutate, toString

Methods inherited from class io.jenetics.AbstractAlterer

probability

Methods inherited from class java.lang.Object

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

Methods inherited from interface io.jenetics.Alterer

andThen, compose

Constructor Details

SwapMutator

public SwapMutator(double probability)

Constructs an alterer with a given recombination probability.

Parameters:

probability - the crossover probability.

Throws:

IllegalArgumentException - if the probability is not in the valid range of [0, 1].

SwapMutator

public SwapMutator()

Default constructor, with default mutation probability (Alterer.DEFAULT_ALTER_PROBABILITY).

Method Details

mutate

protected MutatorResult<Chromosome<G>> mutate(Chromosome<G> chromosome,
 double p,
 RandomGenerator random)

Swaps the genes in the given array, with the mutation probability of this mutation.

Overrides:

mutate in class Mutator<G extends Gene<?,G>,C extends Comparable<? super C>>

Parameters:

chromosome - the chromosome to mutate

p - the mutation probability for the underlying genetic objects

random - the random engine used for the genotype mutation

Returns:

the mutation result

See Also:

• Mutator.mutate(Gene, RandomGenerator)