001    /*
002     * Copyright (C) 2008-2010 by Holger Arndt
003     *
004     * This file is part of the Universal Java Matrix Package (UJMP).
005     * See the NOTICE file distributed with this work for additional
006     * information regarding copyright ownership and licensing.
007     *
008     * UJMP is free software; you can redistribute it and/or modify
009     * it under the terms of the GNU Lesser General Public License as
010     * published by the Free Software Foundation; either version 2
011     * of the License, or (at your option) any later version.
012     *
013     * UJMP is distributed in the hope that it will be useful,
014     * but WITHOUT ANY WARRANTY; without even the implied warranty of
015     * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
016     * GNU Lesser General Public License for more details.
017     *
018     * You should have received a copy of the GNU Lesser General Public
019     * License along with UJMP; if not, write to the
020     * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
021     * Boston, MA  02110-1301  USA
022     */
023    
024    package org.ujmp.core.doublematrix.calculation.general.decomposition;
025    
026    import org.ujmp.core.Matrix;
027    import org.ujmp.core.doublematrix.calculation.AbstractDoubleCalculation;
028    import org.ujmp.core.exceptions.MatrixException;
029    
030    public class Princomp extends AbstractDoubleCalculation {
031            private static final long serialVersionUID = -6137993493011004670L;
032    
033            private Matrix pca = null;
034    
035            public Princomp(Matrix matrix) {
036                    super(matrix);
037            }
038    
039            
040            public double getDouble(long... coordinates) throws MatrixException {
041                    if (pca == null) {
042    
043                            Matrix[] usv;
044                            usv = getSource().svd();
045                            Matrix u = usv[0];
046                            Matrix s = usv[1];
047                            pca = u.mtimes(s);
048    
049                    }
050                    return pca.getAsDouble(coordinates);
051            }
052    
053    }