/*******************************************************************************
* Copyright 2012 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.schedulers;
import java.util.Map;
import org.eclipse.jdt.annotation.Nullable;
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.options.BPOptions;
import com.analog.lyric.dimple.schedulers.schedule.FixedSchedule;
import com.analog.lyric.dimple.schedulers.schedule.ISchedule;
import com.analog.lyric.dimple.schedulers.scheduleEntry.EdgeScheduleEntry;
import com.analog.lyric.dimple.schedulers.scheduleEntry.NodeScheduleEntry;
import com.analog.lyric.dimple.solvers.interfaces.ISolverFactorGraph;
import com.analog.lyric.dimple.solvers.interfaces.SolverNodeMapping;
/**
* @author jeffb
*
* This class generates a sequential schedule on a graph. This schedule
* updates each factor sequentially. Prior to updating each factor, the
* edge from each neighboring variable to that factor is updated.
*
* This scheduler respects any schedulers already assigned to
* sub-graphs. That is, if a sub-graph already has a scheduler
* associated with it, that scheduler will be used for that sub-graph
* instead of this one.
*
* Implements setSubGraphScheduler method, which allows modifying the
* default scheduler used for sub-graphs. This is useful in cases where
* this scheduler is used as a fall-back to a different scheduler.
*/
public class SequentialScheduler extends BPSchedulerBase
{
private static final long serialVersionUID = 1L;
/*-------
* State
*/
protected Class<? extends IScheduler> _subGraphSchedulerClass = SequentialScheduler.class;
/*--------------
* Construction
*/
public SequentialScheduler()
{
}
SequentialScheduler(SequentialScheduler other)
{
_subGraphSchedulerClass = other._subGraphSchedulerClass;
}
/*----------------
* Object methods
*/
@Override
public int hashCode()
{
return getClass().hashCode() + 13 * _subGraphSchedulerClass.hashCode();
}
@Override
public boolean equals(@Nullable Object obj)
{
return obj instanceof SequentialScheduler &&
((SequentialScheduler)obj)._subGraphSchedulerClass == _subGraphSchedulerClass;
}
/*----------------------
* IOptionValue methods
*/
/**
* This type of scheduler is mutable.
* @see #setSubGraphScheduler(Class)
*/
@Override
public boolean isMutable()
{
return true;
}
/*--------------------
* IScheduler methods
*/
@Override
public IScheduler copy(Map<Object, Object> old2NewMap, boolean copyToRoot)
{
return new SequentialScheduler(this);
}
@Override
public ISchedule createSchedule(ISolverFactorGraph solverGraph)
{
return createSchedule(solverGraph.getModelObject(), solverGraph.getSolverMapping());
}
@Override
public ISchedule createSchedule(FactorGraph graph)
{
return createSchedule(graph, null);
}
private ISchedule createSchedule(FactorGraph g, @Nullable SolverNodeMapping solverMap)
{
FixedSchedule schedule = new FixedSchedule(this, g);
// Update all owned functions
for (Factor f : g.getNonGraphFactorsTop())
{
// For each function, update variable edges connecting to that function
for (int i = 0, end = f.getSiblingCount(); i < end; ++i)
{
final EdgeState edge = f.getSiblingEdgeState(i);
schedule.add(new EdgeScheduleEntry(edge.getVariable(g), edge.getVariableToFactorEdgeNumber()));
}
// Then update the function
schedule.add(new NodeScheduleEntry(f));
}
// Update all sub-graphs
for (FactorGraph sg : g.getOwnedGraphs())
{
// For each sub-graph, update the variable edges connecting to that sub-graph
for (int i = 0, end = sg.getSiblingCount(); i < end; ++i)
{
final EdgeState edge = sg.getSiblingEdgeState(i);
schedule.add(new EdgeScheduleEntry(edge.getVariable(g), edge.getVariableToFactorEdgeNumber()));
}
// Then update the sub-graph
IScheduler subscheduler = null;
if (solverMap != null)
{
ISolverFactorGraph ssg = solverMap.getSolverGraphOrNull(sg);
if (ssg != null)
{
subscheduler = ssg.getLocalOption(BPOptions.scheduler);
}
}
if (subscheduler == null)
{
subscheduler = sg.getLocalOption(BPOptions.scheduler);
}
if (subscheduler == null)
{
// If scheduler has not been set on the solver or model subgraph, then use the
// subgraph scheduler.
subscheduler = SchedulerBase.instantiateClass(_subGraphSchedulerClass);
}
schedule.add(sg);
}
return schedule;
}
@SuppressWarnings("all")
public void setSubGraphScheduler(Class<? extends IScheduler> schedulerClass)
{
_subGraphSchedulerClass = SchedulerBase.validateClass(schedulerClass);
}
}