/***********************************************************************
This file is part of KEEL-software, the Data Mining tool for regression,
classification, clustering, pattern mining and so on.
Copyright (C) 2004-2010
F. Herrera (herrera@decsai.ugr.es)
L. S�nchez (luciano@uniovi.es)
J. Alcal�-Fdez (jalcala@decsai.ugr.es)
S. Garc�a (sglopez@ujaen.es)
A. Fern�ndez (alberto.fernandez@ujaen.es)
J. Luengo (julianlm@decsai.ugr.es)
This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see http://www.gnu.org/licenses/
**********************************************************************/
package keel.Algorithms.Fuzzy_Rule_Learning.Shared.Fuzzy;
/**
* <p>
* Represents a singleton fuzzy set.
* A Fuzzy singleton is a fuzzy set whose support is a single point in U with a membership level of 1.0.
* </p>
*
* <p>
* @author Written by Luciano S�nchez (University of Oviedo) 20/01/2004
* @author Modified by Enrique A. de la Cal (University of Oviedo) 13/12/2008
* @version 1.0
* @since JDK1.4
* </p>
*/
public class FuzzySingleton extends Fuzzy {
//it's the single point.
double center;
/**
* <p>
* A constructor for a singleton fuzzy set, given the point.
*
* </p>
* @param c the single point of the fuzzy set.
*/
public FuzzySingleton(double c) {
center=c;
}
/**
* <p>
* A copy constructor for a singleton fuzzy set, given other singleton fuzzy set.
*
* </p>
* @param b to be copied.
*/
public FuzzySingleton(FuzzySingleton b) {
center=b.center;
}
/**
* <p>
* Indicates whether some other object is "equal to" this one.
*
* </p>
* @param b the reference object with which to compare.
* @return true if this object is the same as the B argument; false otherwise.
*/
public boolean equals(Fuzzy b) {
if (!(b instanceof FuzzySingleton)) return false;
FuzzySingleton bt=(FuzzySingleton) b;
if (center!=bt.center) return false;
return true;
}
/**
* <p>
* Creates and returns a copy of this object.
*
* </p>
* @return a clone of this instance.
*/
public Fuzzy clone() {
return new FuzzySingleton(this);
}
/**
* <p>
* Copies the FuzzySingleton parameter over the present instance.
*
* </p>
* @param b a FuzzySingleton object to be copied
*/
public void set(FuzzySingleton b) {
center=b.center;
}
/**
* <p>
* Returns the membership level for the individual x.
*
*
* </p>
* @param x the individual which membership is to be calculated.
* @return the membership level for individual x.
*/
public double evaluateMembership(double x) {
if (x==center) return 1;
return 0;
}
/**
* <p>
* Returns the centroid of the present fuzzy number.
*
* </p>
* @return the centroid of the present fuzzy number.
*/
public double massCentre() {
return center;
}
/**
* <p>
* Creates and returns a FuzzyInterval with unique point of the support set.
*
* </p>
* @return an interval with the unique point of the support set.
*/
public FuzzyInterval support() {
return new FuzzyInterval(center,center);
}
/**
* <p>
* Returns a printable version of the instance.
*
* </p>
* @return a String with a printable version of the singleton fuzzy set.
*/
public String aString() {
return "SINGLE("+center+")";
}
}