eaLib API Docs
Last Modified : January 7 2002

mss.ea.eval
Class LogarithmicScaling

java.lang.Object
  |
  +--mss.ea.core.GeneticOperator
        |
        +--mss.ea.eval.FitnessScaling
              |
              +--mss.ea.eval.LogarithmicScaling
All Implemented Interfaces:
SingleStreamProcessor, StreamProcessor

public class LogarithmicScaling
extends FitnessScaling

Logarithmic fitness scaling. The scaling is calculated based on the formula fitness(i) = a - log( score(i) ). The operator works with all scores, which return a Number as a score value.

Since:
0.1
Version:
0.1 (06-24-2001)
Author:
Andreas Rummler

Field Summary
protected  float a
          Parameter for scaling function.
 
Fields inherited from class mss.ea.core.GeneticOperator
description, ID, name
 
Constructor Summary
LogarithmicScaling(float a)
          Constructor.
 
Method Summary
 Fitness evaluate(Individual ind)
          Evaluation.
 
Methods inherited from class mss.ea.eval.FitnessScaling
process
 
Methods inherited from class mss.ea.core.GeneticOperator
getDescription, getID, getName, toString
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait
 
Methods inherited from interface mss.ea.core.StreamProcessor
getName
 

Field Detail

a

protected float a
Parameter for scaling function.
Constructor Detail

LogarithmicScaling

public LogarithmicScaling(float a)
Constructor.
Parameters:
a - scaling parameter a
Method Detail

evaluate

public Fitness evaluate(Individual ind)
                 throws FitnessScalingException
Evaluation.
Overrides:
evaluate in class FitnessScaling
Parameters:
ind - individual to calculate the fitness for
Returns:
calculated fitness
Throws:
FitnessScalingException - thrown in case of incompatible score

eaLib API Docs
Last Modified : January 7 2002

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