Module org.cicirello.chips_n_salsa
Class KPointCrossover<T extends RealVector>
java.lang.Object
org.cicirello.search.operators.reals.KPointCrossover<T>
 Type Parameters:
T
 The specific RealVector type, such asRealVector
orBoundedRealVector
.
 All Implemented Interfaces:
Splittable<CrossoverOperator<T>>
,CrossoverOperator<T>
public final class KPointCrossover<T extends RealVector>
extends Object
implements CrossoverOperator<T>
Implementation of Kpoint crossover, but for RealVectors. Kpoint crossover is a generalization
of twopoint crossover. In a Kpoint crossover, K random cross points are chosen uniformly along
the length of the parents. Both parents are cut at the K cross points, breaking the parents into
multiple segments. The elements within every other segment are then swapped between the two
parents to form the two children. Kpoint crossover originated for crossover of bit vectors
within a genetic algorithm, but has been adapted here for vectors of doubles.

Constructor Summary

Method Summary
Modifier and TypeMethodDescriptionvoid
cross
(RealVector c1, RealVector c2) Performs a crossover for an evolutionary algorithm, such that crossover forms two children from two parents.split()
Generates a functionally identical copy of this object, for use in multithreaded implementations of search algorithms.

Constructor Details

KPointCrossover
public KPointCrossover(int k) Constructs a Kpoint crossover operator. Parameters:
k
 The number of cross points, which must be at least 1. Although, if you want only a single cross point, you should instead useSinglePointCrossover
; and likewise, if you only want 2 cross points, you should instead useTwoPointCrossover
. Throws:
IllegalArgumentException
 if k is less than 1


Method Details

cross
Performs a crossover for an evolutionary algorithm, such that crossover forms two children from two parents. Implementations of this method modify the parameters, transforming the parents into the children.Behavior is undefined if the RealVectors are of different lengths.
 Specified by:
cross
in interfaceCrossoverOperator<T extends RealVector>
 Parameters:
c1
 A candidate solution subject to the crossover. This method changes the state of c1.c2
 A candidate solution subject to the crossover. This method changes the state of c2. Throws:
IllegalArgumentException
 if c1.length() is less than k.

split
Description copied from interface:Splittable
Generates a functionally identical copy of this object, for use in multithreaded implementations of search algorithms. The state of the object that is returned may or may not be identical to that of the original. Thus, this is a distinct concept from the functionality of theCopyable
interface. Classes that implement this interface must ensure that the object returned performs the same functionality, and that it does not share any state data that would be either unsafe or inefficient for concurrent access by multiple threads. The split method is allowed to simply return the this reference, provided that it is both safe and efficient for multiple threads to share a single copy of the Splittable object. The intention is to provide a multithreaded search with the capability to provide spawned threads with their own distinct search operators. Such multithreaded algorithms can call the split method for each thread it spawns to generate a functionally identical copy of the operator, but with independent state. Specified by:
split
in interfaceSplittable<T extends RealVector>
 Returns:
 A functionally identical copy of the object, or a reference to this if it is both safe and efficient for multiple threads to share a single instance of this Splittable object.
