/*
* RateCovarianceStatistic.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.evomodel.tree;
import dr.evolution.tree.NodeRef;
import dr.evolution.tree.Tree;
import dr.evomodel.branchratemodel.BranchRateModel;
import dr.inference.model.Statistic;
import dr.stats.DiscreteStatistics;
/**
* A statistic that tracks the covariance of rates on branches
*
* @author Alexei Drummond
* @version $Id: RateCovarianceStatistic.java,v 1.5 2005/07/11 14:06:25 rambaut Exp $
*/
public class RateCovarianceStatistic extends Statistic.Abstract implements TreeStatistic {
public RateCovarianceStatistic(String name, Tree tree, BranchRateModel branchRateModel) {
super(name);
this.tree = tree;
this.branchRateModel = branchRateModel;
int n = tree.getExternalNodeCount();
childRate = new double[2 * n - 4];
parentRate = new double[childRate.length];
}
public void setTree(Tree tree) {
this.tree = tree;
}
public Tree getTree() {
return tree;
}
public int getDimension() {
return 1;
}
/**
* @return the height of the MRCA node.
*/
public double getStatisticValue(int dim) {
int n = tree.getNodeCount();
int index = 0;
for (int i = 0; i < n; i++) {
NodeRef child = tree.getNode(i);
NodeRef parent = tree.getParent(child);
if (parent != null & !tree.isRoot(parent)) {
childRate[index] = branchRateModel.getBranchRate(tree, child);
parentRate[index] = branchRateModel.getBranchRate(tree, parent);
index += 1;
}
}
return DiscreteStatistics.covariance(childRate, parentRate);
}
private Tree tree = null;
private BranchRateModel branchRateModel = null;
private double[] childRate = null;
private double[] parentRate = null;
}