001/**
002 * Copyright (C) 2007 - 2016, Jens Lehmann
003 *
004 * This file is part of DL-Learner.
005 *
006 * DL-Learner is free software; you can redistribute it and/or modify
007 * it under the terms of the GNU General Public License as published by
008 * the Free Software Foundation; either version 3 of the License, or
009 * (at your option) any later version.
010 *
011 * DL-Learner is distributed in the hope that it will be useful,
012 * but WITHOUT ANY WARRANTY; without even the implied warranty of
013 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
014 * GNU General Public License for more details.
015 *
016 * You should have received a copy of the GNU General Public License
017 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
018 */
019package org.dllearner.algorithms.decisiontrees.dsttdt.dst;
020
021import java.util.ArrayList;
022
023import org.dllearner.algorithms.decisiontrees.dsttdt.dst.MassFunction;
024
025/**
026 * Utility for building MassFunction  (for now the method supports only a binary frame of discernment)
027 * @author Utente
028 *
029 */
030public class DSTUtils {
031        
032        
033        public static MassFunction<Integer> getBBA(int posExs, int negExs,int undExs) {
034                ArrayList<Integer> set = new ArrayList<>();
035                set.add(-1);
036                set.add(1);
037                MassFunction<Integer> mass= new MassFunction<>(set);
038                ArrayList<Integer> positive= new ArrayList<>();
039                positive.add(1);
040                mass.setValues(positive,(double) posExs/(posExs+ negExs+undExs));
041                ArrayList<Integer> negative= new ArrayList<>();
042                negative.add(-1);
043                mass.setValues(negative, (double)negExs/(posExs+ negExs+undExs));
044                mass.setValues(set, (double)undExs/(posExs+ negExs+undExs));
045
046                return mass;
047
048        }
049
050}