/*
* NormalPotentialDerivative.java
*
* Copyright (c) 2002-2017 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.hmc;
import dr.inference.hmc.GradientWrtParameterProvider;
import dr.inference.model.Likelihood;
import dr.inference.model.Parameter;
/**
* @author Max Tolkoff
*/
@Deprecated // TODO Should be implemented in NormalDistribution, etc.
public class NormalPotentialDerivative implements GradientWrtParameterProvider {
double mean;
double stdev;
Parameter parameter;
public NormalPotentialDerivative(double mean, double stdev, Parameter parameter){
this.mean = mean;
this.stdev = stdev;
this.parameter = parameter;
}
@Override
public Likelihood getLikelihood() {
return null;
}
@Override
public Parameter getParameter() {
return parameter;
}
@Override
public int getDimension() {
return parameter.getDimension();
}
@Override
public double[] getGradientLogDensity() {
double[] derivative = new double[parameter.getDimension()];
for (int i = 0; i < derivative.length; i++) {
derivative[i] -= (parameter.getParameterValue(i) - mean) / (stdev * stdev);
/* Sign change */
}
return derivative;
}
}