ec.select

Class MultiSelection

java.lang.Object

ec.BreedingSource

ec.SelectionMethod

ec.select.MultiSelection

All Implemented Interfaces:

Prototype, Setup, RandomChoiceChooserD, Serializable, Cloneable

public class MultiSelection
extends SelectionMethod

MultiSelection is a SelectionMethod which stores some n subordinate SelectionMethods. Each time it must produce an individual, it picks one of these SelectionMethods at random and has it do the production instead.

Typical Number of Individuals Produced Per produce(...) call
Always 1.

Parameters

base.num-selects int >= 1	(The number of subordinate SelectionMethods)
base.select.n classname, inherits and != SelectionMethod	(Subordinate SelectionMethod n)

Default Base
select.multiselect

Parameter bases

base.select.n

Subordinate SelectionMethod n

Version:

1.0

Author:

Sean Luke

See Also:

Serialized Form

Field Summary

Fields

Modifier and Type	Field and Description
static String	P_MULTISELECT
static String	P_NUMSELECTS
static String	P_SELECT
SelectionMethod[]	selects The MultiSelection's individuals
private static long	serialVersionUID

Fields inherited from class ec.SelectionMethod

INDS_PRODUCED

Fields inherited from class ec.BreedingSource

NO_PROBABILITY, P_PROB, probability

Constructor Summary

Constructors

Constructor and Description
MultiSelection()

Method Summary

Methods

Modifier and Type	Method and Description
Object	clone() Creates a new individual cloned from a prototype, and suitable to begin use in its own evolutionary context.
Parameter	defaultBase() Returns the default base for this prototype.
void	preparePipeline(Object hook) A hook which should be passed to all your subsidiary breeding sources.
void	prepareToProduce(EvolutionState s, int subpopulation, int thread) A default version of prepareToProduce which does nothing.
int	produce(int subpopulation, EvolutionState state, int thread) An alternative form of "produce" special to Selection Methods; selects an individual from the given subpopulation and returns its position in that subpopulation.
int	produce(int min, int max, int start, int subpopulation, Individual[] inds, EvolutionState state, int thread) 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.
boolean	produces(EvolutionState state, Population newpop, int subpopulation, int thread) A default version of produces -- this method always returns true under the assumption that the selection method works with all Fitnesses.
void	setup(EvolutionState state, Parameter base) Sets up the BreedingPipeline.

Methods inherited from class ec.SelectionMethod

finishProducing, typicalIndsProduced

Methods inherited from class ec.BreedingSource

getProbability, pickRandom, setProbability, setupProbabilities

Methods inherited from class java.lang.Object

equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

serialVersionUID

private static final long serialVersionUID

See Also:

Constant Field Values

P_NUMSELECTS

public static final String P_NUMSELECTS

See Also:

Constant Field Values

P_SELECT

public static final String P_SELECT

See Also:

Constant Field Values

P_MULTISELECT

public static final String P_MULTISELECT

See Also:

Constant Field Values

selects

public SelectionMethod[] selects

The MultiSelection's individuals

Constructor Detail

MultiSelection

public MultiSelection()

Method Detail

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(...).

clone

public Object clone()

Description copied from interface: Prototype

Creates a new individual cloned from a prototype, and suitable to begin use in its own evolutionary context.

Typically this should be a full "deep" clone. However, you may share certain elements with other objects rather than clone hem, depending on the situation:

• If you hold objects which are shared with other instances, don't clone them.
• If you hold objects which must be unique, clone them.
• If you hold objects which were given to you as a gesture of kindness, and aren't owned by you, you probably shouldn't clone them.
• DON'T attempt to clone: Singletons, Cliques, or Groups.
• Arrays are not cloned automatically; you may need to clone an array if you're not sharing it with other instances. Arrays have the nice feature of being copyable by calling clone() on them.

Implementations.

• If no ancestor of yours implements clone(), and you have no need to do clone deeply, and you are abstract, then you should not declare clone().
• If no ancestor of yours implements clone(), and you have no need to do clone deeply, and you are not abstract, then you should implement it as follows:

   public Object clone() 
       {
       try
           { 
           return super.clone();
           }
       catch ((CloneNotSupportedException e)
           { throw new InternalError(); } // never happens
       }
          

• If no ancestor of yours implements clone(), but you need to deep-clone some things, then you should implement it as follows:

   public Object clone() 
       {
       try
           { 
           MyObject myobj = (MyObject) (super.clone());
  
           // put your deep-cloning code here...
           }
       catch ((CloneNotSupportedException e)
           { throw new InternalError(); } // never happens
       return myobj;
       } 
          

• If an ancestor has implemented clone(), and you also need to deep clone some things, then you should implement it as follows:

   public Object clone() 
       { 
       MyObject myobj = (MyObject) (super.clone());
  
       // put your deep-cloning code here...
  
       return myobj;
       } 
          

Specified by:

clone in interface Prototype

Overrides:

clone in class BreedingSource

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 BreedingSource

See Also:

Prototype.setup(EvolutionState,Parameter)

produces

public boolean produces(EvolutionState state,
               Population newpop,
               int subpopulation,
               int thread)

Description copied from class: SelectionMethod

A default version of produces -- this method always returns true under the assumption that the selection method works with all Fitnesses. If this isn't the case, you should override this to return your own assessment.

Overrides:

produces in class SelectionMethod

prepareToProduce

public void prepareToProduce(EvolutionState s,
                    int subpopulation,
                    int thread)

Description copied from class: SelectionMethod

A default version of prepareToProduce which does nothing.

Overrides:

prepareToProduce in class SelectionMethod

produce

public int produce(int subpopulation,
          EvolutionState state,
          int thread)

Description copied from class: SelectionMethod

An alternative form of "produce" special to Selection Methods; selects an individual from the given subpopulation and returns its position in that subpopulation.

Specified by:

produce in class SelectionMethod

produce

public int produce(int min,
          int max,
          int start,
          int subpopulation,
          Individual[] inds,
          EvolutionState state,
          int thread)

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.

Overrides:

produce in class SelectionMethod

preparePipeline

public void preparePipeline(Object hook)

Description copied from class: BreedingSource

A hook which should be passed to all your subsidiary breeding sources. The default does this for you already, so ordinarily you don't need to change anything. If you are a BreedingPipeline and you implement your sources in a way different than using the sources[] array, be sure to override this method so that it calls preparePipeline(hook) on all of your sources.

ECJ at present does not custom-implement or call this method: it's available for you. Becuase it has custom functionality, this method might get called more than once, and by various objects as needed. If you use it, you should determine somehow how to use it to send information under the assumption that it might be sent by nested items in the pipeline; you don't want to scribble over each other's calls! Note that this method should travel *all* breeding source paths regardless of whether or not it's redundant to do so.

Overrides:

preparePipeline in class BreedingSource