/*
* MatrixInverseStatistic.java
*
* Copyright (c) 2002-2015 Alexei Drummond, Andrew Rambaut and Marc Suchard
*
* 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 dr.inference.model;
import dr.math.matrixAlgebra.Matrix;
import dr.xml.*;
/**
* @author Marc A. Suchard
*/
public class MatrixInverseStatistic extends Statistic.Abstract implements VariableListener {
public static final String INVERSE_STATISTIC = "matrixInverse";
public MatrixInverseStatistic(MatrixParameter matrix) {
this.matrix = matrix;
matrix.addParameterListener(this);
}
public int getDimension() {
return matrix.getDimension();
}
public double getStatisticValue(int dim) {
if (!inverseKnown) {
inverse = (new Matrix(matrix.getParameterAsMatrix()).inverse().toComponents());
inverseKnown = true;
}
int x = dim / matrix.getColumnDimension();
int y = dim - x * matrix.getColumnDimension();
return inverse[x][y];
}
public String getDimensionName(int dim) {
return getStatisticName() + "." + matrix.getDimensionName(dim);
}
public void variableChangedEvent(Variable variable, int index, Parameter.ChangeType type) {
inverseKnown = false;
}
public static XMLObjectParser PARSER = new AbstractXMLObjectParser() {
public String getParserName() {
return INVERSE_STATISTIC;
}
public Object parseXMLObject(XMLObject xo) throws XMLParseException {
MatrixParameter matrix = (MatrixParameter) xo.getChild(MatrixParameter.class);
if (matrix.getColumnDimension() != matrix.getRowDimension())
throw new XMLParseException("Only square matrices can be inverted");
return new MatrixInverseStatistic(matrix);
}
//************************************************************************
// AbstractXMLObjectParser implementation
//************************************************************************
public String getParserDescription() {
return "This element returns a statistic that is the matrix inverse of the child statistic.";
}
public Class getReturnType() {
return MatrixInverseStatistic.class;
}
public XMLSyntaxRule[] getSyntaxRules() {
return rules;
}
private XMLSyntaxRule[] rules = new XMLSyntaxRule[]{
new ElementRule(MatrixParameter.class)
};
};
private boolean inverseKnown = false;
private double[][] inverse;
private MatrixParameter matrix;
}