/*********************************************************************** This file is part of KEEL-software, the Data Mining tool for regression, classification, clustering, pattern mining and so on. Copyright (C) 2004-2010 F. Herrera (herrera@decsai.ugr.es) L. S�nchez (luciano@uniovi.es) J. Alcal�-Fdez (jalcala@decsai.ugr.es) S. Garc�a (sglopez@ujaen.es) A. Fern�ndez (alberto.fernandez@ujaen.es) J. Luengo (julianlm@decsai.ugr.es) This program is free software: you can redistribute it and/or modify it under the terms of the GNU 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 General Public License for more details. You should have received a copy of the GNU General Public License along with this program. If not, see http://www.gnu.org/licenses/ **********************************************************************/ /* * MachineAccuracy.java * * Copyright (C) 2002-2006 Alexei Drummond and Andrew Rambaut * * This file is part of BEAST. * See the NOTICE file distributed with this work for additional * information regarding copyright ownership and licensing. * * BEAST is free software; you can redistribute it and/or modify * it under the terms of the GNU Lesser General Public License as * published by the Free Software Foundation; either version 2 * of the License, or (at your option) any later version. * * BEAST 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 Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with BEAST; if not, write to the * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor, * Boston, MA 02110-1301 USA */ package keel.Algorithms.Preprocess.Missing_Values.EM.util; /** * determines machine accuracy * * @version $Id: MachineAccuracy.java,v 1.1 2010-07-03 22:51:08 keel Exp $ * * @author Korbinian Strimmer * @author Alexei Drummond */ public class MachineAccuracy { // // Public stuff // /** machine accuracy constant */ public static double EPSILON = 2.220446049250313E-16; public static double SQRT_EPSILON = 1.4901161193847656E-8; public static double SQRT_SQRT_EPSILON = 1.220703125E-4; /** compute EPSILON from scratch */ public static double computeEpsilon() { double eps = 1.0; while( eps + 1.0 != 1.0 ) { eps /= 2.0; } eps *= 2.0; return eps; } /** * @return true if the relative difference between the two parameters * is smaller than SQRT_EPSILON. */ public static boolean same(double a, double b) { return Math.abs((a/b)-1.0) <= SQRT_EPSILON; } }