ec.app.regression
Class Regression

java.lang.Object
  ec.Problem
      ec.gp.GPProblem
          ec.app.regression.Regression

All Implemented Interfaces:

Prototype, Setup, SimpleProblemForm, java.io.Serializable, java.lang.Cloneable

Direct Known Subclasses:

Quintic, Sextic

public class Regression
extends GPProblem
implements SimpleProblemForm

Regression implements the Koza (quartic) Symbolic Regression problem.

The equation to be regressed is y = x^4 + x^3 + x^2 + x, {x in [-1,1]}

This equation was introduced in J. R. Koza, GP II, 1994.

Parameters

base.data classname, inherits or == ec.app.regression.RegressionData	(the class for the prototypical GPData object for the Regression problem)
base.size int >= 1	(the size of the training set)

Parameter bases

base.data

species (the GPData object)

Version:

1.0

Author:

Sean Luke

See Also:

Serialized Form

Field Summary

double	currentValue
RegressionData	input
double[]	inputs
double[]	outputs
static java.lang.String	P_SIZE
int	trainingSetSize

Fields inherited from class ec.gp.GPProblem

data, P_DATA, P_GPPROBLEM, P_STACK, stack

Fields inherited from class ec.Problem

P_PROBLEM

Constructor Summary

Regression()

Method Summary

java.lang.Object	clone() Creates a new individual cloned from a prototype, and suitable to begin use in its own evolutionary context.
void	evaluate(EvolutionState state, Individual ind, int subpopulation, int threadnum) Evaluates the individual in ind, if necessary (perhaps not evaluating them if their evaluated flags are true), and sets their fitness appropriately.
double	func(double x)
void	setup(EvolutionState state, Parameter base) Sets up the object by reading it from the parameters stored in state, built off of the parameter base base.

Methods inherited from class ec.gp.GPProblem

defaultBase, describe

Methods inherited from class ec.Problem

canEvaluate, closeContacts, describe, evaluate, finishEvaluating, getBase, initializeContacts, prepareToEvaluate, reinitializeContacts, setBase

Methods inherited from class java.lang.Object

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

Methods inherited from interface ec.simple.SimpleProblemForm

canEvaluate, describe, describe, evaluate

Field Detail

P_SIZE

public static final java.lang.String P_SIZE

See Also:

Constant Field Values

currentValue

public double currentValue

trainingSetSize

public int trainingSetSize

inputs

public double[] inputs

outputs

public double[] outputs

input

public RegressionData input

Constructor Detail

Regression

public Regression()

Method Detail

func

public double func(double x)

clone

public java.lang.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 GPProblem

setup

public void setup(EvolutionState state,
                  Parameter base)

Description copied from interface: Prototype

Sets up the object by reading it from the parameters stored in state, built off of the parameter base base. If an ancestor implements this method, be sure to call super.setup(state,base); before you do anything else.

For prototypes, setup(...) is typically called once for the prototype instance; cloned instances do not receive the setup(...) call. setup(...) may be called more than once; the only guarantee is that it will get called at least once on an instance or some "parent" object from which it was ultimately cloned.

Specified by:

setup in interface Prototype

Specified by:

setup in interface Setup

Overrides:

setup in class GPProblem

evaluate

public void evaluate(EvolutionState state,
                     Individual ind,
                     int subpopulation,
                     int threadnum)

Description copied from interface: SimpleProblemForm

Evaluates the individual in ind, if necessary (perhaps not evaluating them if their evaluated flags are true), and sets their fitness appropriately.

Specified by:

evaluate in interface SimpleProblemForm

Overrides:

evaluate in class Problem