ExampleBasedSimilarityMeasure.java

/*
 *  RapidMiner
 *
 *  Copyright (C) 2001-2008 by Rapid-I and the contributors
 *
 *  Complete list of developers available at our web site:
 *
 *       http://rapid-i.com
 *
 *  This program is free software: you can redistribute it and/or modify
 *  it under the terms of the GNU Affero 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 Affero General Public License for more details.
 *
 *  You should have received a copy of the GNU Affero General Public License
 *  along with this program.  If not, see http://www.gnu.org/licenses/.
 */
package com.rapidminer.operator.similarity.attributebased;

import com.rapidminer.example.Example;
import com.rapidminer.example.ExampleSet;
import com.rapidminer.operator.OperatorException;
import com.rapidminer.operator.similarity.SimilarityMeasure;


/**
 * Interface for similarities, that can be directly evaluated on examples.
 * 
 * @author Michael Wurst
 * @version $Id: ExampleBasedSimilarityMeasure.java,v 1.5 2008/09/12 10:31:16 tobiasmalbrecht Exp $
 */
public interface ExampleBasedSimilarityMeasure extends SimilarityMeasure {

	/**
	 * Initialize the similarity measure with an example set. Note: In general it is assumed that the example set is not copied.
	 * 
	 * @param exampleSet
	 *            the examples set
	 * @throws OperatorException
	 */
	public void init(ExampleSet exampleSet) throws OperatorException;

	/**
	 * Calculated the similarity of two examples.
	 * 
	 * @param x
	 *            the first example
	 * @param y
	 *            the second examples
	 * @return the similarity/distance or NaN if this value is undefined
	 */
	public double similarity(Example x, Example y);
}