Module org.cicirello.chips_n_salsa
Package org.cicirello.search.operators.reals

Class KPointCrossover<T extends RealVector>

java.lang.Object
org.cicirello.search.operators.reals.KPointCrossover<T>
Type Parameters:
T - The specific RealVector type, such as RealVector or BoundedRealVector.
All Implemented Interfaces:
Splittable<CrossoverOperator<T>>, CrossoverOperator<T>
public final class KPointCrossover<T extends RealVector> extends Object implements CrossoverOperator<T>
Implementation of K-point crossover, but for RealVectors. K-point crossover is a generalization of two-point crossover. In a K-point 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. K-point crossover originated for crossover of bit vectors within a genetic algorithm, but has been adapted here for vectors of doubles.

  • Constructor Details

    • KPointCrossover

      public KPointCrossover(int k)
      Constructs a K-point 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 use SinglePointCrossover; and likewise, if you only want 2 cross points, you should instead use TwoPointCrossover.
      Throws:
      IllegalArgumentException - if k is less than 1

  • Method Details

    • cross

      public void cross(RealVector c1, RealVector c2)
      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 interface CrossoverOperator<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

      public KPointCrossover<T> 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 the Copyable 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 interface Splittable<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.