/*
 *  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.features;

import com.rapidminer.example.AttributeWeights;
import com.rapidminer.example.ExampleSet;
import com.rapidminer.example.set.AttributeWeightedExampleSet;
import com.rapidminer.operator.IOObject;
import com.rapidminer.operator.Operator;
import com.rapidminer.operator.OperatorDescription;
import com.rapidminer.operator.OperatorException;


/**
 * <p>This operator deselects attributes with a weight value of 0.0. The values of
 * the other numeric attributes will be recalculated based on the
 * weights delivered as {@link AttributeWeights}
 * object in the input.</p>
 * 
 * <p>This operator can hardly be used to select a subset of
 * features according to weights determined by a former weighting scheme. For this purpose
 * the operator
 * {@link com.rapidminer.operator.features.selection.AttributeWeightSelection}
 * should be used which will select only those attribute fulfilling a specified 
 * weight relation.</p> 
 * 
 * @author Ingo Mierswa
 * @version $Id: AttributeWeightsApplier.java,v 2.11 2006/04/14 15:04:22
 *          ingomierswa Exp $
 */
public class AttributeWeightsApplier extends Operator {

	private static final Class[] INPUT_CLASSES = { ExampleSet.class, AttributeWeights.class };

	private static final Class[] OUTPUT_CLASSES = { ExampleSet.class };

	public AttributeWeightsApplier(OperatorDescription description) {
		super(description);
	}

	public IOObject[] apply() throws OperatorException {
		AttributeWeights weights = getInput(AttributeWeights.class);
		ExampleSet exampleSet = getInput(ExampleSet.class);

		AttributeWeightedExampleSet weightedSet = new AttributeWeightedExampleSet(exampleSet, weights);
		ExampleSet result = weightedSet.createCleanClone();
		
		return new IOObject[] { result };
	}

	public Class<?>[] getInputClasses() {
		return INPUT_CLASSES;
	}

	public Class<?>[] getOutputClasses() {
		return OUTPUT_CLASSES;
	}
}