/*
 *  RapidMiner
 *
 *  Copyright (C) 2001-2011 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.tools.math.function.aggregation;

import com.rapidminer.example.Attribute;

/**
 * This aggregation function calculates the product of
 * all given values.
 * 
 * @author Sebastian Land
 *
 */
public class ProductFunction extends AbstractAggregationFunction {

	private double product = 1d;
	
	public ProductFunction() {}
	
	public ProductFunction(Boolean ignoreMissings) {
		super(ignoreMissings);
	}
	
	@Override
	protected void reset() {
		this.product = 1d;
	}

	@Override
	public String getName() {
		return "product";
	}

	@Override
	public double getValue() {
		return product;
	}

	@Override
	public boolean supportsAttribute(Attribute attribute) {
		return attribute.isNumerical();
	}

	@Override
	public void update(double value, double weight) {
		if (!Double.isNaN(value) && !Double.isNaN(weight))
			product *= (value * weight);
	}

	@Override
	public void update(double value) {
		if (!Double.isNaN(value))
			product *= value;
	}
}