Module io.jenetics.base
Package io.jenetics

Class IntermediateCrossover<G extends NumericGene<?,G>,C extends Comparable<? super C>>

java.lang.Object
io.jenetics.AbstractAlterer<G,C>
io.jenetics.Recombinator<G,C>
io.jenetics.Crossover<G,C>
io.jenetics.IntermediateCrossover<G,C>
All Implemented Interfaces:
Alterer<G,C>
public class IntermediateCrossover<G extends NumericGene<?,G>,C extends Comparable<? super C>> extends Crossover<G,C>
This alterer takes two chromosomes (treating it as vectors) and creates a linear combination of these vectors as a result. The line-recombination depends on a variable p which determines how far out along the line (defined by the two multidimensional points/vectors) the children are allowed to be. If p = 0 then the children will be located along the line within the hypercube between the two points. If p > 0 then the children may be located anywhere on the line, even somewhat outside the hypercube.

Points outside the allowed numeric range are rejected, and new points are generated until they lie in the valid range. The strategy on how out-of-range points are handled, is the difference to the very similar LineCrossover.

Since:
3.8
Version:
3.8
See Also:

  • Constructor Details

    • IntermediateCrossover

      public IntermediateCrossover(double probability, double p)
      Creates a new intermediate-crossover with the given recombination probability and the line-scaling factor p.

      When the value for p is greater then 0, the crossover point generation must be repeated until the points lie within the allowed range. Values greater then 10 are usually not recommended, since this leads to unnecessary crossover point generation.

      Parameters:
      probability - the recombination probability.
      p - defines the possible location of the recombined chromosomes. If p = 0 then the children will be located along the line within the hypercube between the two points. If p > 0 then the children may be located anywhere on the line, even somewhat outside the hypercube.
      Throws:
      IllegalArgumentException - if the probability is not in the valid range of [0, 1] or if p is smaller then zero

    • IntermediateCrossover

      public IntermediateCrossover(double probability)
      Creates a new intermediate-crossover with the given recombination probability. The parameter p is set to zero, which restricts the recombined chromosomes within the hypercube of the selected chromosomes (vectors).
      Parameters:
      probability - the recombination probability.
      Throws:
      IllegalArgumentException - if the probability is not in the valid range of [0, 1]

    • IntermediateCrossover

      public IntermediateCrossover()
      Creates a new intermediate-crossover with default recombination probability (Alterer.DEFAULT_ALTER_PROBABILITY) and a p value of zero, which restricts the recombined chromosomes within the hypercube of the selected chromosomes (vectors).

  • Method Details

    • crossover

      protected int crossover(MSeq<G> v, MSeq<G> w)
      Description copied from class: Crossover
      Template method which performs the crossover. The arguments given are mutable non-null arrays of the same length.
      Specified by:
      crossover in class Crossover<G extends NumericGene<?,G>,C extends Comparable<? super C>>
      Parameters:
      v - the genes of the first chromosome
      w - the genes of the other chromosome
      Returns:
      the number of altered genes

    • toString

      public String toString()
      Overrides:
      toString in class Object