AbstractCrossover (Watchmaker Framework for Evolutionary Computation API 0.7.1)

java.lang.Object
- org.uncommons.watchmaker.framework.operators.AbstractCrossover<T>

Type Parameters:

T - The type of evolved candidates that are operated on by this cross-over implementation.

All Implemented Interfaces:

EvolutionaryOperator<T>

Direct Known Subclasses:

BitStringCrossover, ByteArrayCrossover, CharArrayCrossover, DoubleArrayCrossover, IntArrayCrossover, ListCrossover, ListOrderCrossover, ObjectArrayCrossover, StringCrossover
```
public abstract class AbstractCrossover<T>
extends Object
implements EvolutionaryOperator<T>
```
Generic base class for cross-over implementations. Supports all cross-over processes that operate on a pair of parent candidates.

Constructor Summary

Constructors
Modifier	Constructor and Description
`protected`	`AbstractCrossover(int crossoverPoints)` Sets up a fixed-point cross-over implementation.
`protected`	`AbstractCrossover(int crossoverPoints, Probability crossoverProbability)` Sets up a cross-over implementation that uses a fixed number of cross-over points.
`protected`	`AbstractCrossover(NumberGenerator<Integer> crossoverPointsVariable)` Sets up a cross-over implementation that uses a variable number of cross-over points.
`protected`	`AbstractCrossover(NumberGenerator<Integer> crossoverPointsVariable, NumberGenerator<Probability> crossoverProbabilityVariable)` Sets up a cross-over implementation that uses a variable number of cross-over points.

Method Summary

All Methods Instance Methods Abstract Methods Concrete Methods
Modifier and Type	Method and Description
`List<T>`	`apply(List<T> selectedCandidates, Random rng)` Applies the cross-over operation to the selected candidates.
`protected abstract List<T>`	`mate(T parent1, T parent2, int numberOfCrossoverPoints, Random rng)` Perform cross-over on a pair of parents to generate a pair of offspring.

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Constructor Detail
  - AbstractCrossover
```
protected AbstractCrossover(int crossoverPoints)
```
    Sets up a fixed-point cross-over implementation. Cross-over is applied to all pairs of parents. To apply cross-over only to a proportion of parent pairs, use the AbstractCrossover(int, Probability) constructor.
    
    Parameters:
    
    crossoverPoints - The constant number of cross-over points to use for all cross-over operations.
  - AbstractCrossover
```
protected AbstractCrossover(int crossoverPoints,
                            Probability crossoverProbability)
```
    Sets up a cross-over implementation that uses a fixed number of cross-over points. Cross-over is applied to a proportion of selected parent pairs, with the remainder copied unchanged into the output population. The size of this evolved proportion is controlled by the crossoverProbability parameter.
    
    Parameters:
    
    crossoverPoints - The constant number of cross-over points to use for all cross-over operations.
    
    crossoverProbability - The probability that, once selected, a pair of parents will be subjected to cross-over rather than being copied, unchanged, into the output population. Must be in the range 0 < crossoverProbability <= 1
  - AbstractCrossover
```
protected AbstractCrossover(NumberGenerator<Integer> crossoverPointsVariable)
```
    Sets up a cross-over implementation that uses a variable number of cross-over points. Cross-over is applied to all pairs of parents. To apply cross-over only to a proportion of parent pairs, use the AbstractCrossover(NumberGenerator, NumberGenerator) constructor.
    
    Parameters:
    
    crossoverPointsVariable - A random variable that provides a number of cross-over points for each cross-over operation.
  - AbstractCrossover
```
protected AbstractCrossover(NumberGenerator<Integer> crossoverPointsVariable,
                            NumberGenerator<Probability> crossoverProbabilityVariable)
```
    Sets up a cross-over implementation that uses a variable number of cross-over points. Cross-over is applied to a proportion of selected parent pairs, with the remainder copied unchanged into the output population. The size of this evolved proportion is controlled by the crossoverProbabilityVariable parameter.
    
    Parameters:
    
    crossoverPointsVariable - A variable that provides a (possibly constant, possibly random) number of cross-over points for each cross-over operation.
    
    crossoverProbabilityVariable - A variable that controls the probability that, once selected, a pair of parents will be subjected to cross-over rather than being copied, unchanged, into the output population.
- Method Detail
  - apply
```
public List<T> apply(List<T> selectedCandidates,
                     Random rng)
```
    Applies the cross-over operation to the selected candidates. Pairs of candidates are chosen randomly and subjected to cross-over to produce a pair of offspring candidates.
    
    Specified by:
    
    apply in interface EvolutionaryOperator<T>
    
    Parameters:
    
    selectedCandidates - The evolved individuals that have survived to be eligible to reproduce.
    
    rng - A source of randomness used to determine the location of cross-over points.
    
    Returns:
    
    The combined set of evolved offspring generated by applying cross-over to the the selected candidates.
  - mate
```
protected abstract List<T> mate(T parent1,
                                T parent2,
                                int numberOfCrossoverPoints,
                                Random rng)
```
    Perform cross-over on a pair of parents to generate a pair of offspring.
    
    Parameters:
    
    parent1 - One of two individuals that provides the source material for generating offspring.
    
    parent2 - One of two individuals that provides the source material for generating offspring.
    
    numberOfCrossoverPoints - The number of cross-overs performed on the two parents.
    
    rng - A source of randomness used to determine the location of cross-over points.
    
    Returns:
    
    A list containing two evolved offspring.

Class AbstractCrossover<T>

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Constructor Detail

AbstractCrossover

AbstractCrossover

AbstractCrossover

AbstractCrossover

Method Detail

apply

mate