ec.de

Class Best1BinDEBreeder

java.lang.Object

ec.Breeder

ec.de.DEBreeder

ec.de.Best1BinDEBreeder

All Implemented Interfaces:

Setup, Singleton, java.io.Serializable

public class Best1BinDEBreeder
extends DEBreeder

Best1BinDEBreeder is a differential evolution breeding operator. The code is derived from a DE algorithm, known as DE/best/1/bin "with uniform jitter", found on page 140 of "Differential Evolution: A Practical Approach to Global Optimization" by Kenneth Price, Rainer Storn, and Jouni Lampinen.

Best1BinDEBreeder requires that all individuals be DoubleVectorIndividuals.

In short, the algorithm is as follows. For each individual in the population, we produce a child by first selecting the best individual in the population, which we call r0. We then select two more (different) individuals, none the original individual nor r0, called r1 and r2. We then create an individal c, defined as c = r0 + FJitter() * (r1 - r2), where FJitter() is a per-gene independent random number defined as F + F_NOISE * (random(0,1) - 0.5). A common value for F_NOISE is 0.001. Last, we cross over c with the original individual and produce a single child, using uniform crossover with gene-independent crossover probability "Cr".

This class should be used in conjunction with DEEvaluator, which allows the children to enter the population only if they're superior to their parents (the original individuals). If so, they replace their parents.

Parameters

base.f-noise 0.0 <= double

The "F_NOISE" jitter value

See Also:

Serialized Form

Field Summary

Fields

Modifier and Type	Field and Description
double	F_NOISE limits on uniform noise for F
static java.lang.String	P_FNOISE

Fields inherited from class ec.de.DEBreeder

bestSoFarIndex, Cr, CR_UNSPECIFIED, F, P_Cr, P_F, P_OUT_OF_BOUNDS_RETRIES, previousPopulation, retries

Constructor Summary

Constructors

Constructor and Description
Best1BinDEBreeder()

Method Summary

Modifier and Type	Method and Description
DoubleVectorIndividual	createIndividual(EvolutionState state, int subpop, int index, int thread)
void	setup(EvolutionState state, Parameter base) Sets up the object by reading it from the parameters stored in state, built off of the parameter base base.

Methods inherited from class ec.de.DEBreeder

breedPopulation, crossover, prepareDEBreeder, valid

Methods inherited from class java.lang.Object

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

Field Detail

F_NOISE

public double F_NOISE

limits on uniform noise for F

P_FNOISE

public static final java.lang.String P_FNOISE

See Also:

Constant Field Values

Constructor Detail

Best1BinDEBreeder

public Best1BinDEBreeder()

Method Detail

setup

public void setup(EvolutionState state,
                  Parameter base)

Description copied from interface: Setup

Sets up the object by reading it from the parameters stored in state, built off of the parameter base base. If an ancestor implements this method, be sure to call super.setup(state,base); before you do anything else.

Specified by:

setup in interface Setup

Overrides:

setup in class DEBreeder

createIndividual

public DoubleVectorIndividual createIndividual(EvolutionState state,
                                               int subpop,
                                               int index,
                                               int thread)

Overrides:

createIndividual in class DEBreeder