nrc.fuzzy
Class FuzzyRuleExecutor

java.lang.Object
  |
  +--nrc.fuzzy.FuzzyRuleExecutor

All Implemented Interfaces:

java.lang.Cloneable, FuzzyRuleExecutorInterface, java.io.Serializable

Direct Known Subclasses:

LarsenProductMaxMinRuleExecutor, MamdaniMinMaxMinRuleExecutor, TsukamotoRuleExecutor

public abstract class FuzzyRuleExecutor

extends java.lang.Object

implements FuzzyRuleExecutorInterface, java.lang.Cloneable, java.io.Serializable

An abstract class that can be sub-classed to provide an execute method that accepts a FuzzyRule object and returns a FuzzyValueVector composed of the actual output FuzzyValues for the rule (using the implication operator and composition operator that the specific interface implements). For example, the execute method may implement rule execution using the Mamdani Min inference operator and Max-Min composition. This is due to the FuzzyRuleExecutorInterface interface. It must also implement the cloneable interface and provide a clone method so that we can guarantee that when a Rule is created it gets a unique instance of the rule executor. All FuzzyRules have a FuzzyRuleExecutor associated with them. This defines the method (algorithm) that will be used for calculating the output FuzzyValues of a rule, given the antecedents, inputs and conclusions in the FuzzyRule. In general each FuzzyRule must have a unique instance of a FuzzyRuleExecutor associated with it. This will allow the Rule Executors to save state between firings of the same rule and when possible avoid redoing some calculations, after testing that the rule contents (antecedents, inputs, and conclusions) have not changed enough to invalidate previous calculations. For example, the MamdaniMinMaxMinRuleExecutor implements the Mamdani Min inference operator and the Max-Min composition operator to calculate a rule's outputs. This method has the rather nice property that the outputs are generated from the conclusions by 'clipping' them at a value that is calculated as the minimum of the maximum membership values of the intersections of the fuzzy value antecedent and input pairs. So one can calculate the intersections of the pairs get the maximum membership value for each intersection and find the minimum of these. Should the rule be fired a second time and the antecedents and inputs have not changed, it is only necessary to clip the consequents, avoiding some expensive calculations.

See Also:

MamdaniMinMaxMinRuleExecutor, LarsenProductMaxMinRuleExecutor, FuzzyRule, Serialized Form

Constructor Summary

FuzzyRuleExecutor()

Methods inherited from class java.lang.Object

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

Methods inherited from interface nrc.fuzzy.FuzzyRuleExecutorInterface

execute, execute

Constructor Detail

FuzzyRuleExecutor

public FuzzyRuleExecutor()