io.jenetics.engine

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

java.lang.Object

io.jenetics.engine.EvolutionResult<G,C>

Type Parameters:

G - the gene type

C - the fitness type

All Implemented Interfaces:

Serializable, Comparable<EvolutionResult<G,C>>

public final class EvolutionResult<G extends Gene<?,G>,C extends Comparable<? super C>>
extends Object
implements Comparable<EvolutionResult<G,C>>, Serializable

Represents a state of the GA after an evolution step. It also represents the final state of an evolution process and can be created with an appropriate collector:

final Problem<ISeq<Point>, EnumGene<Point>, Double> tsm = ...; final EvolutionResult<EnumGene<Point>, Double> result = Engine.builder(tsm) .optimize(Optimize.MINIMUM).build() .stream() .limit(100) .collect(EvolutionResult.toBestEvolutionResult());

Since:

3.0

Version:

4.0

Author:

Franz Wilhelmstötter

See Also:

EvolutionStart, Engine, Serialized Form

Implementation Note:

This class is immutable and thread-safe.

Method Summary

Modifier and Type	Method and Description
int	compareTo(EvolutionResult<G,C> other) Compare this evolution result with another one, according the populations best individual.
boolean	equals(Object obj)
int	getAlterCount() The number of altered individuals.
C	getBestFitness() Return the best population fitness.
Phenotype<G,C>	getBestPhenotype() Return the best Phenotype of the result population.
EvolutionDurations	getDurations() Return the timing (meta) information of the evolution step.
long	getGeneration() The current generation.
ISeq<Genotype<G>>	getGenotypes() Return the current list of genotypes of this evolution result.
int	getInvalidCount() Return the number of invalid individuals.
int	getKillCount() Return the number of killed individuals.
Optimize	getOptimize() Return the optimization strategy used.
ISeq<Phenotype<G,C>>	getPopulation() Return the population after the evolution step.
long	getTotalGenerations() Return the generation count evaluated so far.
C	getWorstFitness() Return the worst population fitness.
Phenotype<G,C>	getWorstPhenotype() Return the worst Phenotype of the result population.
int	hashCode()
EvolutionStart<G,C>	next() Return the next evolution start object with the current population and the incremented generation.
static <G extends Gene<?,G>,C extends Comparable<? super C>> EvolutionResult<G,C>	of(Optimize optimize, ISeq<Phenotype<G,C>> population, long generation, EvolutionDurations durations, int killCount, int invalidCount, int alterCount) Return an new EvolutionResult object with the given values.
static <G extends Gene<?,G>,C extends Comparable<? super C>> EvolutionResult<G,C>	of(Optimize optimize, ISeq<Phenotype<G,C>> population, long generation, long totalGenerations, EvolutionDurations durations, int killCount, int invalidCount, int alterCount) Return an new EvolutionResult object with the given values.
static <G extends Gene<?,G>,C extends Comparable<? super C>> Collector<EvolutionResult<G,C>,?,EvolutionResult<G,C>>	toBestEvolutionResult() Return a collector which collects the best result of an evolution stream.
static <G extends Gene<?,G>,C extends Comparable<? super C>> Collector<EvolutionResult<G,C>,?,Genotype<G>>	toBestGenotype() Return a collector which collects the best genotype of an evolution stream.
static <G extends Gene<?,G>,C extends Comparable<? super C>> Collector<EvolutionResult<G,C>,?,Phenotype<G,C>>	toBestPhenotype() Return a collector which collects the best phenotype of an evolution stream.
static <G extends Gene<?,G>,C extends Comparable<? super C>,T> Collector<EvolutionResult<G,C>,?,T>	toBestResult(Codec<T,G> codec) Return a collector which collects the best result (in the native problem space).
static <G extends Gene<?,G>,C extends Comparable<? super C>,T> Collector<EvolutionResult<G,C>,?,T>	toBestResult(Function<Genotype<G>,T> decoder) Return a collector which collects the best result (in the native problem space).
EvolutionStart<G,C>	toEvolutionStart() Return the current evolution result object as an EvolutionStart object with the current population and current total generation.
static <G extends Gene<?,G>,C extends Comparable<? super C>> UnaryOperator<EvolutionResult<G,C>>	toUniquePopulation() Return a mapping function, which removes duplicate individuals from the population and replaces it with newly created one by the existing genotype factory.
static <G extends Gene<?,G>,C extends Comparable<? super C>> UnaryOperator<EvolutionResult<G,C>>	toUniquePopulation(Factory<Genotype<G>> factory) Return a mapping function, which removes duplicate individuals from the population and replaces it with newly created one by the given genotype factory.
static <G extends Gene<?,G>,C extends Comparable<? super C>> UnaryOperator<EvolutionResult<G,C>>	toUniquePopulation(Factory<Genotype<G>> factory, int maxRetries) Return a mapping function, which removes duplicate individuals from the population and replaces it with newly created one by the given genotype factory.
static <G extends Gene<?,G>,C extends Comparable<? super C>> UnaryOperator<EvolutionResult<G,C>>	toUniquePopulation(int maxRetries) Return a mapping function, which removes duplicate individuals from the population and replaces it with newly created one by the existing genotype factory.

Methods inherited from class java.lang.Object

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

Method Detail

getOptimize

public Optimize getOptimize()

Return the optimization strategy used.

Returns:

the optimization strategy used

getPopulation

public ISeq<Phenotype<G,C>> getPopulation()

Return the population after the evolution step.

Returns:

the population after the evolution step

getGenotypes

public ISeq<Genotype<G>> getGenotypes()

Return the current list of genotypes of this evolution result.

Returns:

the list of genotypes of this evolution result.

Since:

3.9

getGeneration

public long getGeneration()

The current generation.

Returns:

the current generation

getTotalGenerations

public long getTotalGenerations()

Return the generation count evaluated so far.

Returns:

the total number of generations evaluated so far

getDurations

public EvolutionDurations getDurations()

Return the timing (meta) information of the evolution step.

Returns:

the timing (meta) information of the evolution step

getKillCount

public int getKillCount()

Return the number of killed individuals.

Returns:

the number of killed individuals

getInvalidCount

public int getInvalidCount()

Return the number of invalid individuals.

Returns:

the number of invalid individuals

getAlterCount

public int getAlterCount()

The number of altered individuals.

Returns:

the number of altered individuals

getBestPhenotype

public Phenotype<G,C> getBestPhenotype()

Return the best Phenotype of the result population.

Returns:

the best Phenotype of the result population

getWorstPhenotype

public Phenotype<G,C> getWorstPhenotype()

Return the worst Phenotype of the result population.

Returns:

the worst Phenotype of the result population

getBestFitness

public C getBestFitness()

Return the best population fitness.

Returns:

The best population fitness.

getWorstFitness

public C getWorstFitness()

Return the worst population fitness.

Returns:

The worst population fitness.

next

public EvolutionStart<G,C> next()

Return the next evolution start object with the current population and the incremented generation.

Returns:

the next evolution start object

Since:

4.1

toEvolutionStart

public EvolutionStart<G,C> toEvolutionStart()

Return the current evolution result object as an EvolutionStart object with the current population and current total generation.

Returns:

the current result as evolution start

Since:

4.1

compareTo

public int compareTo(EvolutionResult<G,C> other)

Compare this evolution result with another one, according the populations best individual.

Specified by:

compareTo in interface Comparable<EvolutionResult<G extends Gene<?,G>,C extends Comparable<? super C>>>

Parameters:

other - the other evolution result to compare

Returns:

a negative integer, zero, or a positive integer as this result is less than, equal to, or greater than the specified result.

hashCode

public int hashCode()

Overrides:

hashCode in class Object

equals

public boolean equals(Object obj)

Overrides:

equals in class Object

toBestEvolutionResult

public static <G extends Gene<?,G>,C extends Comparable<? super C>> Collector<EvolutionResult<G,C>,?,EvolutionResult<G,C>> toBestEvolutionResult()

Return a collector which collects the best result of an evolution stream.

final Problem<ISeq<Point>, EnumGene<Point>, Double> tsm = ...; final EvolutionResult<EnumGene<Point>, Double> result = Engine.builder(tsm) .optimize(Optimize.MINIMUM).build() .stream() .limit(100) .collect(EvolutionResult.toBestEvolutionResult());

If the collected EvolutionStream is empty, the collector returns null.

Type Parameters:

G - the gene type

C - the fitness type

Returns:

a collector which collects the best result of an evolution stream

toBestPhenotype

public static <G extends Gene<?,G>,C extends Comparable<? super C>> Collector<EvolutionResult<G,C>,?,Phenotype<G,C>> toBestPhenotype()

Return a collector which collects the best phenotype of an evolution stream.

final Problem<ISeq<Point>, EnumGene<Point>, Double> tsm = ...; final Phenotype<EnumGene<Point>, Double> result = Engine.builder(tsm) .optimize(Optimize.MINIMUM).build() .stream() .limit(100) .collect(EvolutionResult.toBestPhenotype());

If the collected EvolutionStream is empty, the collector returns null.

Type Parameters:

G - the gene type

C - the fitness type

Returns:

a collector which collects the best phenotype of an evolution stream

toBestGenotype

public static <G extends Gene<?,G>,C extends Comparable<? super C>> Collector<EvolutionResult<G,C>,?,Genotype<G>> toBestGenotype()

Return a collector which collects the best genotype of an evolution stream.

final Problem<ISeq<Point>, EnumGene<Point>, Double> tsm = ...; final Genotype<EnumGene<Point>> result = Engine.builder(tsm) .optimize(Optimize.MINIMUM).build() .stream() .limit(100) .collect(EvolutionResult.toBestGenotype());

If the collected EvolutionStream is empty, the collector returns null.

Type Parameters:

G - the gene type

C - the fitness type

Returns:

a collector which collects the best genotype of an evolution stream

toBestResult

public static <G extends Gene<?,G>,C extends Comparable<? super C>,T> Collector<EvolutionResult<G,C>,?,T> toBestResult(Function<Genotype<G>,T> decoder)

Return a collector which collects the best result (in the native problem space).

final Problem<ISeq<Point>, EnumGene<Point>, Double> tsm = ...; final ISeq<Point> route = Engine.builder(tsm) .optimize(Optimize.MINIMUM).build() .stream() .limit(100) .collect(EvolutionResult.toBestResult(tsm.codec().decoder()));

If the collected EvolutionStream is empty, the collector returns null.

Type Parameters:

T - the native problem result type

G - the gene type

C - the fitness result type

Parameters:

decoder - the decoder which converts the Genotype into the result of the problem space.

Returns:

a collector which collects the best result of an evolution stream

Throws:

NullPointerException - if the given decoder is null

Since:

3.6

toBestResult

public static <G extends Gene<?,G>,C extends Comparable<? super C>,T> Collector<EvolutionResult<G,C>,?,T> toBestResult(Codec<T,G> codec)

Return a collector which collects the best result (in the native problem space).

final Problem<ISeq<Point>, EnumGene<Point>, Double> tsm = ...; final ISeq<Point> route = Engine.builder(tsm) .optimize(Optimize.MINIMUM).build() .stream() .limit(100) .collect(EvolutionResult.toBestResult(tsm.codec()));

If the collected EvolutionStream is empty, the collector returns null.

Type Parameters:

T - the native problem result type

G - the gene type

C - the fitness result type

Parameters:

codec - the problem decoder

Returns:

a collector which collects the best result of an evolution stream

Throws:

NullPointerException - if the given codec is null

Since:

3.6

toUniquePopulation

public static <G extends Gene<?,G>,C extends Comparable<? super C>> UnaryOperator<EvolutionResult<G,C>> toUniquePopulation(Factory<Genotype<G>> factory,
                                                                                                                           int maxRetries)

Return a mapping function, which removes duplicate individuals from the population and replaces it with newly created one by the given genotype factory.

final Problem<Double, DoubleGene, Integer> problem = ...; final Engine<DoubleGene, Integer> engine = Engine.builder(problem) .mapping(EvolutionResult.toUniquePopulation(problem.codec().encoding(), 100)) .build(); final Genotype<DoubleGene> best = engine.stream() .limit(100); .collect(EvolutionResult.toBestGenotype());

Type Parameters:

G - the gene type

C - the fitness function result type

Parameters:

factory - the genotype factory which create new individuals

maxRetries - the maximal number of genotype creation tries

Returns:

a mapping function, which removes duplicate individuals from the population

Throws:

NullPointerException - if the given genotype factory is null

Since:

4.0

See Also:

Engine.Builder.mapping(Function)

toUniquePopulation

public static <G extends Gene<?,G>,C extends Comparable<? super C>> UnaryOperator<EvolutionResult<G,C>> toUniquePopulation(Factory<Genotype<G>> factory)

Return a mapping function, which removes duplicate individuals from the population and replaces it with newly created one by the given genotype factory.

final Problem<Double, DoubleGene, Integer> problem = ...; final Engine<DoubleGene, Integer> engine = Engine.builder(problem) .mapping(EvolutionResult.toUniquePopulation(problem.codec().encoding())) .build(); final Genotype<DoubleGene> best = engine.stream() .limit(100); .collect(EvolutionResult.toBestGenotype());

Type Parameters:

G - the gene type

C - the fitness function result type

Parameters:

factory - the genotype factory which create new individuals

Returns:

a mapping function, which removes duplicate individuals from the population

Throws:

NullPointerException - if the given genotype factory is null

Since:

4.0

See Also:

Engine.Builder.mapping(Function)

toUniquePopulation

public static <G extends Gene<?,G>,C extends Comparable<? super C>> UnaryOperator<EvolutionResult<G,C>> toUniquePopulation(int maxRetries)

Return a mapping function, which removes duplicate individuals from the population and replaces it with newly created one by the existing genotype factory.

final Problem<Double, DoubleGene, Integer> problem = ...; final Engine<DoubleGene, Integer> engine = Engine.builder(problem) .mapping(EvolutionResult.toUniquePopulation(10)) .build(); final Genotype<DoubleGene> best = engine.stream() .limit(100); .collect(EvolutionResult.toBestGenotype(5));

Type Parameters:

G - the gene type

C - the fitness function result type

Parameters:

maxRetries - the maximal number of genotype creation tries

Returns:

a mapping function, which removes duplicate individuals from the population

Throws:

NullPointerException - if the given genotype factory is null

Since:

4.0

See Also:

Engine.Builder.mapping(Function)

toUniquePopulation

public static <G extends Gene<?,G>,C extends Comparable<? super C>> UnaryOperator<EvolutionResult<G,C>> toUniquePopulation()

Return a mapping function, which removes duplicate individuals from the population and replaces it with newly created one by the existing genotype factory.

final Problem<Double, DoubleGene, Integer> problem = ...; final Engine<DoubleGene, Integer> engine = Engine.builder(problem) .mapping(EvolutionResult.toUniquePopulation()) .build(); final Genotype<DoubleGene> best = engine.stream() .limit(100); .collect(EvolutionResult.toBestGenotype());

Type Parameters:

G - the gene type

C - the fitness function result type

Returns:

a mapping function, which removes duplicate individuals from the population

Throws:

NullPointerException - if the given genotype factory is null

Since:

4.0

See Also:

Engine.Builder.mapping(Function)

of

public static <G extends Gene<?,G>,C extends Comparable<? super C>> EvolutionResult<G,C> of(Optimize optimize,
                                                                                            ISeq<Phenotype<G,C>> population,
                                                                                            long generation,
                                                                                            long totalGenerations,
                                                                                            EvolutionDurations durations,
                                                                                            int killCount,
                                                                                            int invalidCount,
                                                                                            int alterCount)

Return an new EvolutionResult object with the given values.

Type Parameters:

G - the gene type

C - the fitness type

Parameters:

optimize - the optimization strategy used

population - the population after the evolution step

generation - the current generation

totalGenerations - the overall number of generations

durations - the timing (meta) information

killCount - the number of individuals which has been killed

invalidCount - the number of individuals which has been removed as invalid

alterCount - the number of individuals which has been altered

Returns:

an new evolution result object

Throws:

NullPointerException - if one of the parameters is null

of

public static <G extends Gene<?,G>,C extends Comparable<? super C>> EvolutionResult<G,C> of(Optimize optimize,
                                                                                            ISeq<Phenotype<G,C>> population,
                                                                                            long generation,
                                                                                            EvolutionDurations durations,
                                                                                            int killCount,
                                                                                            int invalidCount,
                                                                                            int alterCount)

Return an new EvolutionResult object with the given values.

Type Parameters:

G - the gene type

C - the fitness type

Parameters:

optimize - the optimization strategy used

population - the population after the evolution step

generation - the current generation

durations - the timing (meta) information

killCount - the number of individuals which has been killed

invalidCount - the number of individuals which has been removed as invalid

alterCount - the number of individuals which has been altered

Returns:

an new evolution result object

Throws:

NullPointerException - if one of the parameters is null