/* * 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.window; /** * A Blackman-Harris window function. * * @author Tobias Malbrecht, Ingo Mierswa */ public class BlackmanHarrisWindowFunction extends WindowFunction { public BlackmanHarrisWindowFunction(Integer width) { super(width); } public BlackmanHarrisWindowFunction(Integer width, Integer justification) { super(width, justification); } @Override protected double getValue(int width, int n) { return 0.35875 - 0.48829 * Math.cos(2 * Math.PI * n / width) + 0.14128 * Math.cos(4 * Math.PI * n / width) - 0.01168 * Math.cos(6 * Math.PI * n / width); } }