/*
* 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.generator;
/** The label is att1 - (int)att1.
*
* @author Ingo Mierswa
* @version $Id: TriangularFunction.java,v 1.3 2008/05/09 19:22:50 ingomierswa Exp $
*/
public class TriangularFunction extends RegressionFunction {
public double calculate(double[] args) throws FunctionException {
if (args.length != 1)
throw new FunctionException("Triangular function", "needs 1 attributes!");
// double a = 100.0d;
// double b = 5.0d;
// return a * (4.0d * Math.abs(Math.atan(Math.tan((args[0]/ b + 1.0d
// / 4.0d) * Math.PI)) / Math.PI) - 1.0d);
return args[0] - (int) args[0];
}
}