com.anji.neat
Class AddNeuronMutationOperator

java.lang.Object
  org.jgap.MutationOperator
      com.anji.neat.AddNeuronMutationOperator

All Implemented Interfaces:

Configurable

public class AddNeuronMutationOperator
extends MutationOperator
implements Configurable

Implements NEAT add node mutation inspired by Evolving Neural Networks through Augmenting Topologies . In ANJI, mutation rate refers to the likelihood of a new node being created on any existing connection. In traditional NEAT, it is the likelihood of a chromosome experiencing a mutation, and each chromosome can not have more than one topological mutation per generation.

Author:

Philip Tucker

Field Summary

static java.lang.String	ADD_NEURON_MUTATE_RATE_KEY properties key, add neuron mutation rate
static float	DEFAULT_MUTATE_RATE default mutation rate

Constructor Summary

AddNeuronMutationOperator()

AddNeuronMutationOperator(float newMutationRate)

Method Summary

boolean	addNeuronAtConnection(NeatConfiguration config, java.util.Map neurons, ConnectionAllele oldConnectAllele, java.util.Set allelesToAdd, java.util.Set allelesToRemove)
void	init(Properties props)
protected void	mutate(Configuration jgapConfig, ChromosomeMaterial target, java.util.Set allelesToAdd, java.util.Set allelesToRemove) Adds connections according to NEAT add node mutation.

Methods inherited from class org.jgap.MutationOperator

doesMutationOccur, doesMutationOccur, getMutationRate, mutate, numMutations, setMutationRate, updateMaterial

Methods inherited from class java.lang.Object

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

Field Detail

ADD_NEURON_MUTATE_RATE_KEY

public static final java.lang.String ADD_NEURON_MUTATE_RATE_KEY

properties key, add neuron mutation rate

See Also:

Constant Field Values

DEFAULT_MUTATE_RATE

public static final float DEFAULT_MUTATE_RATE

default mutation rate

See Also:

Constant Field Values

Constructor Detail

AddNeuronMutationOperator

public AddNeuronMutationOperator()

See Also:

AddNeuronMutationOperator(float)

AddNeuronMutationOperator

public AddNeuronMutationOperator(float newMutationRate)

See Also:

MutationOperator.MutationOperator(float)

Method Detail

init

public void init(Properties props)
          throws java.lang.Exception

Specified by:

init in interface Configurable

Parameters:

props - configuration parameters

Throws:

java.lang.Exception

See Also:

Configurable.init(com.anji.util.Properties)

mutate

protected void mutate(Configuration jgapConfig,
                      ChromosomeMaterial target,
                      java.util.Set allelesToAdd,
                      java.util.Set allelesToRemove)

Adds connections according to NEAT add node mutation.

Specified by:

mutate in class MutationOperator

target - chromosome material before mutation

allelesToAdd - alleles added by this mutation, Set contains Allele objects

allelesToRemove - alleles removed by this mutation, Set contains Allele objects

See Also:

MutationOperator.mutate(org.jgap.Configuration, org.jgap.ChromosomeMaterial, java.util.Set, java.util.Set)

addNeuronAtConnection

public boolean addNeuronAtConnection(NeatConfiguration config,
                                     java.util.Map neurons,
                                     ConnectionAllele oldConnectAllele,
                                     java.util.Set allelesToAdd,
                                     java.util.Set allelesToRemove)

Parameters:

config -

neurons - Map contains NeuronAllele objects

oldConnectAllele - connection allele to be replaced by neuron

allelesToAdd - Set contains Allele objects

allelesToRemove - Set contains Allele objects

Returns:

true iff neuron added