Package ec.breed

Class GenerationSwitchPipeline

java.lang.Object
ec.BreedingSource
ec.BreedingPipeline
ec.breed.GenerationSwitchPipeline
All Implemented Interfaces:
Prototype, Setup, SteadyStateBSourceForm, RandomChoiceChooserD, Serializable, Cloneable

public class GenerationSwitchPipeline extends BreedingPipeline
GenerationSwitchPipeline is a simple BreedingPipeline which switches its source depending on the generation. If the generation number is invalid input: '<' n, then GenerationSwitchPipeline uses source.0. If the generation number if >= n, then GenerationSwitchPipeline uses source.1.

Important Note: Because GenerationSwitchPipeline gets the generation number from the EvolutionState, and this number is not protected by a mutex, if you create an EvolutionState or Breeder which uses multiple threads that can update the generation number as they like, you could cause a race condition. This doesn't occur with the present EvolutionState objects provided with ECJ, but you should be aware of the possibility.

Typical Number of Individuals Produced Per produce(...) call
Defined as the max of its children's responses.

Number of Sources
2

Parameters

base.generate-max
bool = true (default) or false
(Each time produce(...) is called, should the GenerationSwitchPipeline force all its sources to produce exactly the same number of individuals as the largest typical number of individuals produced by any source in the group?)
base.switch-at
int >= 0
(The generation we will switch at)

Default Base
breed.generation-switch

See Also:
  • Field Details

  • Constructor Details

    • GenerationSwitchPipeline

      public GenerationSwitchPipeline()
  • Method Details

    • defaultBase

      public Parameter defaultBase()
      Description copied from interface: Prototype
      Returns the default base for this prototype. This should generally be implemented by building off of the static base() method on the DefaultsForm object for the prototype's package. This should be callable during setup(...).
    • numSources

      public int numSources()
      Description copied from class: BreedingPipeline
      Returns the number of sources to this pipeline. Called during BreedingPipeline's setup. Be sure to return a value > 0, or DYNAMIC_SOURCES which indicates that setup should check the parameter file for the parameter "num-sources" to make its determination.
      Specified by:
      numSources in class BreedingPipeline
    • setup

      public void setup(EvolutionState state, Parameter base)
      Description copied from class: BreedingSource
      Sets up the BreedingPipeline. You can use state.output.error here because the top-level caller promises to call exitIfErrors() after calling setup. Note that probability might get modified again by an external source if it doesn't normalize right.

      The most common modification is to normalize it with some other set of probabilities, then set all of them up in increasing summation; this allows the use of the fast static BreedingSource-picking utility method, BreedingSource.pickRandom(...). In order to use this method, for example, if four breeding source probabilities are {0.3, 0.2, 0.1, 0.4}, then they should get normalized and summed by the outside owners as: {0.3, 0.5, 0.6, 1.0}.

      Specified by:
      setup in interface Prototype
      Specified by:
      setup in interface Setup
      Overrides:
      setup in class BreedingPipeline
      See Also:
    • typicalIndsProduced

      public int typicalIndsProduced()
      Returns the max of typicalIndsProduced() of all its children
      Overrides:
      typicalIndsProduced in class BreedingPipeline
    • produce

      public int produce(int min, int max, int subpopulation, ArrayList<Individual> inds, EvolutionState state, int thread, HashMap<String,Object> misc)
      Description copied from class: BreedingSource
      Produces n individuals from the given subpopulation and puts them into inds[start...start+n-1], where n = Min(Max(q,min),max), where q is the "typical" number of individuals the BreedingSource produces in one shot, and returns n. max must be >= min, and min must be >= 1. For example, crossover might typically produce two individuals, tournament selection might typically produce a single individual, etc.
      Specified by:
      produce in class BreedingSource