Class SPXCrossover

Namespace

OptunaSharp.Samplers.Nsgaii

Assembly

OptunaSharp.dll

Simplex Crossover operation used by NSGAIISampler. Port of optuna/samplers/nsgaii/_crossovers/_spx.py: SPXCrossover (experimental v3.0.0).

Uniformly samples child individuals from within a single simplex similar to the simplex produced by the (three) parent individuals.

public class SPXCrossover : BaseCrossover

Inheritance

object

BaseCrossover

SPXCrossover

Inherited Members

BaseCrossover.ToString()

object.Equals(object)

object.Equals(object, object)

object.GetHashCode()

object.GetType()

object.MemberwiseClone()

object.ReferenceEquals(object, object)

Constructors

SPXCrossover(double?)

Configures expansion of the simplex formed by three numerical parent vectors.

public SPXCrossover(double? epsilon = null)

Parameters

epsilon double?

Expansion rate. If unset, defaults to sqrt(len(search_space) + 2).

Properties

NParents

Number of parent individuals required to perform crossover.

public override int NParents { get; }

Property Value

int

Methods

Crossover(double[][], NumPyRandom, Study, double[,])

Perform crossover of selected parent individuals.

public override double[] Crossover(double[][] parentsParams, NumPyRandom rng, Study study, double[,] searchSpaceBounds)

Parameters

parentsParams double[][]

A num_parents x num_parameters array. Represents a parameter space for each parent individual (continuous for numerical parameters). Row i is parent i.

rng NumPyRandom

An instance of numpy.random.RandomState.

study Study

Target study object.

searchSpaceBounds double[,]

A len_search_space x 2 array of numerical distribution bounds constructed from the transformed search space. Column 0 is lower, column 1 is upper.

Returns

double[]

A 1-dimensional array containing the new parameter combination.