/*******************************************************************************
* Copyright 2013 Analog Devices, Inc.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
********************************************************************************/
package com.analog.lyric.dimple.solvers.gibbs.customFactors;
import static java.util.Objects.*;
import java.util.ArrayList;
import java.util.HashSet;
import java.util.List;
import java.util.Set;
import org.eclipse.jdt.annotation.Nullable;
import com.analog.lyric.dimple.factorfunctions.Multiplexer;
import com.analog.lyric.dimple.factorfunctions.core.FactorFunction;
import com.analog.lyric.dimple.model.core.EdgeState;
import com.analog.lyric.dimple.model.core.FactorGraph;
import com.analog.lyric.dimple.model.factors.Factor;
import com.analog.lyric.dimple.model.variables.Discrete;
import com.analog.lyric.dimple.model.variables.Variable;
import com.analog.lyric.dimple.solvers.core.parameterizedMessages.IParameterizedMessage;
import com.analog.lyric.dimple.solvers.gibbs.GibbsDiscrete;
import com.analog.lyric.dimple.solvers.gibbs.GibbsDiscreteEdge;
import com.analog.lyric.dimple.solvers.gibbs.GibbsGenericEdge;
import com.analog.lyric.dimple.solvers.gibbs.GibbsReal;
import com.analog.lyric.dimple.solvers.gibbs.GibbsRealFactor;
import com.analog.lyric.dimple.solvers.gibbs.GibbsRealJoint;
import com.analog.lyric.dimple.solvers.gibbs.GibbsSolverEdge;
import com.analog.lyric.dimple.solvers.gibbs.GibbsSolverGraph;
import com.analog.lyric.dimple.solvers.gibbs.ISolverRealVariableGibbs;
import com.analog.lyric.dimple.solvers.gibbs.samplers.ISampler;
import com.analog.lyric.dimple.solvers.gibbs.samplers.conjugate.IConjugateSampler;
import com.analog.lyric.dimple.solvers.gibbs.samplers.conjugate.IRealConjugateSamplerFactory;
import com.analog.lyric.dimple.solvers.gibbs.samplers.conjugate.IRealJointConjugateSampler;
import com.analog.lyric.dimple.solvers.gibbs.samplers.conjugate.IRealJointConjugateSamplerFactory;
import com.analog.lyric.dimple.solvers.interfaces.ISolverVariable;
public class CustomMultiplexer extends GibbsRealFactor implements IRealConjugateFactor, IRealJointConjugateFactor
{
private @Nullable ISampler[] _conjugateSampler;
private @Nullable GibbsDiscrete _selectorVariable;
private @Nullable ISolverRealVariableGibbs _outputVariable;
private int _outputPortNumber;
private int _selectorPortNumber;
private int _firstInputPortNumber;
private int _outputVariableSiblingPortIndex;
private @Nullable int[] _inputPortMap;
private boolean _incompatibleWithConjugateSampling = false;
private boolean _hasFactorFunctionConstants;
private boolean _hasConstantSelector;
private int _selectorConstantValue;
private static final int OUTPUT_INDEX = 0;
private static final int SELECTOR_INDEX = 1;
private static final int FIRST_INPUT_PORT_INDEX = 2;
private static final int NO_PORT = -1;
public CustomMultiplexer(Factor factor, GibbsSolverGraph parent)
{
super(factor, parent);
}
@Override
public GibbsSolverEdge<?> createEdge(EdgeState edge)
{
Variable var = edge.getVariable(_model.requireParentGraph());
if (var instanceof Discrete)
{
return new GibbsDiscreteEdge((Discrete)var);
}
return new GibbsGenericEdge();
}
@SuppressWarnings("null")
@Override
public void updateEdgeMessage(EdgeState modelEdge, GibbsSolverEdge<?> solverEdge)
{
final int portNum = modelEdge.getFactorToVariableEdgeNumber();
if (portNum >= _firstInputPortNumber)
{
// Port is an input port
int selector = _hasConstantSelector ? _selectorConstantValue : _selectorVariable.getCurrentSampleIndex(); // Get the current selector value
if (portNum == _inputPortMap[selector])
{
// Port is the currently selected input port
// Get the aggregated message from the variable connected to the output port
_outputVariable.getAggregateMessages(solverEdge.factorToVarMsg,
_outputVariableSiblingPortIndex, _conjugateSampler[portNum]);
}
else
{
// Port is not the currently selected input port
solverEdge.factorToVarMsg.setNull();
}
}
else
super.updateEdgeMessage(modelEdge, solverEdge);
}
// For Real variable inputs and outputs
@SuppressWarnings("null")
@Override
public Set<IRealConjugateSamplerFactory> getAvailableRealConjugateSamplers(int portNumber)
{
Set<IRealConjugateSamplerFactory> availableSamplers = new HashSet<IRealConjugateSamplerFactory>();
determineConstantsAndEdges(); // Call this here since initialize may not have been called yet
if (_incompatibleWithConjugateSampling)
return availableSamplers;
if (isPortInputVariable(portNumber))
{
final Factor factor = _model;
final FactorGraph fg = factor.requireParentGraph();
// If an input variable, then check conjugacy for the output variable among all of its neighbors except this factor
GibbsReal outputVariable = ((GibbsReal)_outputVariable);
List<EdgeState> outputNeighboringEdges = new ArrayList<>(outputVariable.getSiblingCount() - 1);
for (EdgeState edgeState : outputVariable.getModelObject().getSiblingEdgeState())
{
if (!factor.equals(edgeState.getFactor(fg))) // Don't include this factor to test conjugacy
{
outputNeighboringEdges.add(edgeState);
}
}
availableSamplers.addAll(outputVariable.findConjugateSamplerFactories(outputNeighboringEdges));
}
return availableSamplers;
}
// For RealJoint variable inputs and outputs
@SuppressWarnings("null")
@Override
public Set<IRealJointConjugateSamplerFactory> getAvailableRealJointConjugateSamplers(int portNumber)
{
Set<IRealJointConjugateSamplerFactory> availableSamplers = new HashSet<IRealJointConjugateSamplerFactory>();
determineConstantsAndEdges(); // Call this here since initialize may not have been called yet
if (_incompatibleWithConjugateSampling)
return availableSamplers;
if (isPortInputVariable(portNumber))
{
final Factor factor = _model;
final FactorGraph fg = factor.requireParentGraph();
// If an input variable, then check conjugacy for the output variable among all of its neighbors except this factor
GibbsRealJoint outputVariable = ((GibbsRealJoint)_outputVariable);
List<EdgeState> outputNeighboringEdges = new ArrayList<>(outputVariable.getSiblingCount() - 1);
for (EdgeState edgeState : outputVariable.getModelObject().getSiblingEdgeState())
{
if (!factor.equals(edgeState.getFactor(fg)))
{
outputNeighboringEdges.add(edgeState);
}
}
availableSamplers.addAll(outputVariable.findConjugateSamplerFactories(outputNeighboringEdges));
}
return availableSamplers;
}
public boolean isPortInputVariable(int portNumber)
{
return (portNumber >= _firstInputPortNumber);
}
@SuppressWarnings("null")
@Override
public void initialize()
{
super.initialize();
// Determine if any ports can use a conjugate sampler
final int nEdges = getSiblingCount();
final ISampler[] conjugateSampler = _conjugateSampler = new ISampler[nEdges];
for (int edgeNumber = 0; edgeNumber < nEdges; edgeNumber++)
{
ISolverVariable var = getSibling(edgeNumber);
if (var instanceof GibbsReal)
{
GibbsReal svar = (GibbsReal)var;
conjugateSampler[edgeNumber] = svar.getConjugateSampler();
if (conjugateSampler[edgeNumber] != null)
{
// Create message and tell the variable to use it
IParameterizedMessage msg =
((IConjugateSampler)conjugateSampler[edgeNumber]).createParameterMessage();
getSiblingEdgeState(edgeNumber).factorToVarMsg = msg;
}
}
else if (var instanceof GibbsRealJoint)
{
GibbsRealJoint svar = (GibbsRealJoint)var;
conjugateSampler[edgeNumber] = svar.getConjugateSampler();
if (conjugateSampler[edgeNumber] != null)
{
// Create message and tell the variable to use it
IParameterizedMessage msg =
((IRealJointConjugateSampler)conjugateSampler[edgeNumber]).createParameterMessage();
getSiblingEdgeState(edgeNumber).factorToVarMsg = msg;
}
}
else
conjugateSampler[edgeNumber] = null;
}
// Determine what parameters are constants or edges, and save the state
determineConstantsAndEdges();
// Set up _inputPortMap, which maps the selector value to port index
int numInputEdges = nEdges - _firstInputPortNumber;
final int[] inputPortMap = _inputPortMap = new int[numInputEdges];
if (_hasFactorFunctionConstants)
{
final Factor factor = _model;
int numConstants = factor.getConstantCount();
int numIndices = nEdges + numConstants;
for (int index = 0, port = 0, selectorIndex = 0; index < numIndices; index++)
{
if (factor.hasConstantAtIndex(index))
{
if (index > FIRST_INPUT_PORT_INDEX)
selectorIndex++;
}
else
{
if (port > _firstInputPortNumber)
inputPortMap[selectorIndex++] = port++;
else
port++;
}
}
}
else // No constants
{
for (int i = 0; i < numInputEdges; i++)
inputPortMap[i] = i + _firstInputPortNumber;
}
}
private void determineConstantsAndEdges()
{
// Get the factor function and related state
final Factor factor = _model;
FactorFunction factorFunction = factor.getFactorFunction();
Multiplexer specificFactorFunction = (Multiplexer)factorFunction;
_hasFactorFunctionConstants = factor.hasConstants();
if (specificFactorFunction.hasSmoothing())
{
_incompatibleWithConjugateSampling = true;
return;
}
if (factor.hasConstantAtIndex(OUTPUT_INDEX))
{
_incompatibleWithConjugateSampling = true;
return;
}
_selectorPortNumber = NO_PORT;
_selectorVariable = null;
_selectorConstantValue = -1;
_outputPortNumber = factor.argIndexToSiblingNumber(OUTPUT_INDEX); // Must be a variable if not returned already
ISolverVariable outputVariable = getSibling(_outputPortNumber);
if (outputVariable instanceof ISolverRealVariableGibbs)
_outputVariable = (ISolverRealVariableGibbs)outputVariable;
_outputVariableSiblingPortIndex = _model.getReverseSiblingNumber(_outputPortNumber);
_hasConstantSelector = factor.hasConstantAtIndex(SELECTOR_INDEX);
if (_hasConstantSelector)
{
_selectorConstantValue = requireNonNull(factor.getConstantValueByIndex(SELECTOR_INDEX)).getInt();
_firstInputPortNumber = FIRST_INPUT_PORT_INDEX - 1;
}
else
{
_selectorPortNumber = factor.argIndexToSiblingNumber(SELECTOR_INDEX);
_selectorVariable = (GibbsDiscrete)getSibling(_selectorPortNumber);
_firstInputPortNumber = FIRST_INPUT_PORT_INDEX;
}
}
@Override
public GibbsGenericEdge getSiblingEdgeState(int siblingIndex)
{
return (GibbsGenericEdge)getSiblingEdgeState_(siblingIndex);
}
}