/*
* RLCNarrowExchangeOperator.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.operators;
import dr.evolution.tree.NodeRef;
import dr.evomodel.tree.TreeModel;
import dr.inference.operators.SimpleMCMCOperator;
import dr.math.MathUtils;
import dr.xml.*;
import java.util.ArrayList;
import java.util.List;
/**
* Implements narrow exchange operations while also changing the rates.
* The narrow exchange is very similar to a rooted-tree
* nearest-neighbour interchange but with the restriction
* that node height must remain consistent.
*/
public class RLCNarrowExchangeOperator extends SimpleMCMCOperator {
public static final String NARROW_EXCHANGE = "narrowExchangeRLC";
private static final int MAX_TRIES = 10000;
private final TreeModel tree;
public RLCNarrowExchangeOperator(TreeModel tree, double weight) {
this.tree = tree;
setWeight(weight);
}
public double doOperation() {
int tipCount = tree.getExternalNodeCount();
narrow();
if (tree.getExternalNodeCount() != tipCount) {
throw new RuntimeException("Lost some tips in narrow exchange RLC");
}
return 0.0;
}
/**
* WARNING: Assumes strictly bifurcating tree.
*/
public void narrow() {
final int nNodes = tree.getNodeCount();
final NodeRef root = tree.getRoot();
for (int tries = 0; tries < MAX_TRIES; ++tries) {
NodeRef i = tree.getNode(MathUtils.nextInt(nNodes));
while (root == i || tree.getParent(i) == root) {
i = tree.getNode(MathUtils.nextInt(nNodes));
}
final NodeRef iParent = tree.getParent(i);
final NodeRef iGrandParent = tree.getParent(iParent);
NodeRef iUncle = tree.getChild(iGrandParent, 0);
if (iUncle == iParent) {
iUncle = tree.getChild(iGrandParent, 1);
}
assert tree.getNodeHeight(i) < tree.getNodeHeight(iGrandParent);
if (tree.getNodeHeight(iUncle) < tree.getNodeHeight(iParent)) {
NodeRef iSister = tree.getChild(iParent, 0);
if (iSister == i) {
iSister = tree.getChild(iParent, 1);
}
eupdate(i, iUncle, iParent, iGrandParent, iSister);
tree.pushTreeChangedEvent(iParent);
tree.pushTreeChangedEvent(iGrandParent);
return;
}
}
//System.out.println("tries = " + tries);
throw new RuntimeException("Couldn't find valid narrow move on this tree!!");
}
public String getOperatorName() {
return "Narrow Exchange RLC";
}
/* exchange subtrees whose root are i and j */
private void eupdate(NodeRef i, NodeRef j, NodeRef iP, NodeRef jP, NodeRef iS) {
tree.beginTreeEdit();
tree.removeChild(iP, i);
tree.removeChild(jP, j);
tree.addChild(jP, i);
tree.addChild(iP, j);
tree.endTreeEdit();
List<NodeRef> nodes = new ArrayList<NodeRef>();
nodes.add(i);
nodes.add(iP);
nodes.add(j);
nodes.add(jP);
nodes.add(iS);
NodeRef a = nodes.remove(MathUtils.nextInt(nodes.size()));
NodeRef b = nodes.get(MathUtils.nextInt(nodes.size()));
//swap traits in these two nodes
double changedA = tree.getNodeTrait(a, "trait");
double changedB = tree.getNodeTrait(a, "trait");
tree.setNodeTrait(a, "trait", changedB);
tree.setNodeTrait(b, "trait", changedA);
}
public double getMinimumAcceptanceLevel() {
return 0.05;
}
public double getMinimumGoodAcceptanceLevel() {
return 0.05;
}
public String getPerformanceSuggestion() {
if (Utils.getAcceptanceProbability(this) < getMinimumAcceptanceLevel()) {
return "";
} else if (Utils.getAcceptanceProbability(this) > getMaximumAcceptanceLevel()) {
return "";
} else {
return "";
}
}
public static XMLObjectParser NARROW_EXCHANGE_PARSER = new AbstractXMLObjectParser() {
public String getParserName() {
return NARROW_EXCHANGE;
}
public Object parseXMLObject(XMLObject xo) throws XMLParseException {
TreeModel treeModel = (TreeModel) xo.getChild(TreeModel.class);
double weight = xo.getDoubleAttribute("weight");
return new RLCNarrowExchangeOperator(treeModel, weight);
}
//************************************************************************
// AbstractXMLObjectParser implementation
//************************************************************************
public String getParserDescription() {
return "This element represents a narrow exchange operator. " +
"This operator swaps a random subtree with its uncle.";
}
public Class getReturnType() {
return RLCNarrowExchangeOperator.class;
}
public XMLSyntaxRule[] getSyntaxRules() {
return rules;
}
private final XMLSyntaxRule[] rules = {
AttributeRule.newDoubleRule("weight"),
new ElementRule(TreeModel.class)
};
};
}