/*
* MsatBitFlipOperator.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.inference.model.Parameter;
import dr.inference.operators.MCMCOperator;
import dr.inference.operators.SimpleMCMCOperator;
import dr.xml.*;
import dr.math.MathUtils;
/**
* @author Chieh-Hsi Wu
*
* This operator performs bitflip operation on the bit vector representing the model.
*
*/
public class MicrosatelliteBitFlipOperator extends SimpleMCMCOperator {
private Parameter parameter;
private Parameter dependencies;
private int[] variableIndices;
public static final int PRESENT = 1;
public static final int ABSENT = 0;
public static final int NO_DEPENDENCY = -1;
public static final String MODEL_CHOOSE = "modelChoose";
public static final String DEPENDENCIES = "dependencies";
public static final String VARIABLE_INDICES = "variableIndices";
public MicrosatelliteBitFlipOperator(Parameter parameter, Parameter dependencies, double weight, int[] variableIndices){
this.parameter = parameter;
this.dependencies = dependencies;
this.variableIndices = variableIndices;
if(parameter.getDimension() != dependencies.getDimension())
throw new RuntimeException("Dimenension of the parameter ("+parameter.getDimension()+
") does not equal to the dimension of the dependencies parameter("+dependencies.getDimension()+").");
setWeight(weight);
}
public String getOperatorName(){
return "msatModelSwitch(" + parameter.getParameterName() + ")";
}
public double doOperation() {
double logq = 0.0;
double[] bitVec = new double[parameter.getDimension()];
for(int i = 0; i < bitVec.length; i++){
bitVec[i] = parameter.getParameterValue(i);
}
//int index = (int)Math.random()*parameter.getDimension();
int index = variableIndices[MathUtils.nextInt(variableIndices.length)];
//System.out.println(index);
int oldVal = (int)parameter.getParameterValue(index);
int newVal = -1;
if(oldVal == ABSENT){
newVal = PRESENT;
}else if(oldVal == PRESENT){
newVal = ABSENT;
}else{
throw new RuntimeException("The parameter can only take values 0 or 1.");
}
bitVec[index] = newVal;
for(int i = 0; i < bitVec.length; i++){
int dependentInd = (int)dependencies.getParameterValue(i);
if(dependentInd > NO_DEPENDENCY){
if(bitVec[dependentInd] == ABSENT && bitVec[i]==PRESENT){
//throw new OperatorFailedException("");
return Double.NEGATIVE_INFINITY;
}
}
}
parameter.setParameterValue(index, newVal);
return logq;
}
public final String getPerformanceSuggestion() {
return "no suggestions available";
}
public static dr.xml.XMLObjectParser PARSER = new AbstractXMLObjectParser() {
public String getParserName() {
return "msatModelSwitchOperator";
}
public Object parseXMLObject(XMLObject xo) throws XMLParseException {
double weight = xo.getDoubleAttribute(WEIGHT);
Parameter modelChoose = (Parameter) xo.getElementFirstChild(MODEL_CHOOSE);
Parameter dependencies = (Parameter)xo.getElementFirstChild(DEPENDENCIES);
int[] variableIndices;
if(xo.hasChildNamed(VARIABLE_INDICES)){
double[] temp = ((Parameter)xo.getElementFirstChild(VARIABLE_INDICES)).getParameterValues();
variableIndices = new int[temp.length];
for(int i = 0; i < temp.length;i++){
variableIndices[i] = (int)temp[i];
}
}else{
variableIndices = new int[]{0, 1, 2, 3, 4, 5};
}
return new MicrosatelliteBitFlipOperator(modelChoose, dependencies, weight, variableIndices);
}
//************************************************************************
// AbstractXMLObjectParser implementation
//************************************************************************
public String getParserDescription() {
return "This element returns a microsatellite averaging operator on a given parameter.";
}
public Class getReturnType() {
return MCMCOperator.class;
}
public XMLSyntaxRule[] getSyntaxRules() {
return rules;
}
private XMLSyntaxRule[] rules = new XMLSyntaxRule[]{
AttributeRule.newDoubleRule(WEIGHT),
new ElementRule(MODEL_CHOOSE, new XMLSyntaxRule[]{new ElementRule(Parameter.class)}),
new ElementRule(DEPENDENCIES, new XMLSyntaxRule[]{new ElementRule(Parameter.class)}),
new ElementRule(VARIABLE_INDICES, new XMLSyntaxRule[]{new ElementRule(Parameter.class)},true)
};
};
}