ptolemy.domains.ct.kernel
Class CTMixedSignalDirector

java.lang.Object
  ptolemy.kernel.util.NamedObj
      ptolemy.kernel.util.Attribute
          ptolemy.actor.Director
              ptolemy.actor.sched.StaticSchedulingDirector
                  ptolemy.domains.ct.kernel.CTDirector
                      ptolemy.domains.ct.kernel.CTMultiSolverDirector
                          ptolemy.domains.ct.kernel.CTMixedSignalDirector

All Implemented Interfaces:

java.io.Serializable, java.lang.Cloneable, Executable, Initializable, TimedDirector, CTGeneralDirector, Changeable, Debuggable, DebugListener, Derivable, ModelErrorHandler, MoMLExportable, Moveable, Nameable

public class CTMixedSignalDirector
extends CTMultiSolverDirector

A CTDirector that supports the interaction of the continuous-time simulation with event-based domains. This director can both serve as a top-level director and an inside director that is contained by a composite actor in an event-based domain. If it is a top-level director, it behaves exactly like a CTMultiSolverDirector. If it is embedded in an event-based domain, it will run ahead of the global time and prepare to roll back if necessary.

This director has an extra parameter compared to the CTMultiSolverDirector, the maximum run ahead of time length (runAheadLength). Its default value is 1.0.

The running ahead of time is achieved by the following mechanism.

• At the initialize stage of an execution, the director requests a firing at the global current time.
• At each prefire stage of the execution, the end time the the firing is computed based on the current time of the executive director, t1, the next iteration time of the executive director, t2, and the value of the parameter runAheadLength, t3. The fire end time is t1 + min(t2, t3)
• At the fire stage, the director will stop at the first of the following two times, the fire end time and the time of the first detected event.

At the prefire stage, the local current time is compared with the current time of the executive director. If the local time is later than the executive director time, then the directed system will rollback to a "known good" state. The "known good" state is the state of the system at the time when local time is equal to the current time of the executive director

.

Since:

Ptolemy II 0.2

Version:

$Id: CTMixedSignalDirector.java 57040 2010-01-27 20:52:32Z cxh $

Author:

Jie Liu, Haiyang Zheng

See Also:

Serialized Form

Accepted Rating:

Red (hyzheng)

Proposed Rating:

Yellow (hyzheng)

Nested Class Summary

Nested classes/interfaces inherited from class ptolemy.kernel.util.NamedObj

NamedObj.ContainedObjectsIterator

Field Summary

private boolean	_isTop
private Time	_knownGoodTime
private long	_mutationVersion
private Time	_outsideTime
private double	_runAheadLength
Parameter	runAheadLength Parameter of the run ahead length.

Fields inherited from class ptolemy.domains.ct.kernel.CTMultiSolverDirector

_initialStatesNotReady, breakpointODESolver, ODESolver

Fields inherited from class ptolemy.domains.ct.kernel.CTDirector

_timeBase, errorTolerance, initStepSize, maxIterations, maxStepSize, minStepSize, startTime, stopTime, synchronizeToRealTime, valueResolution

Fields inherited from class ptolemy.actor.sched.StaticSchedulingDirector

_postfireReturns

Fields inherited from class ptolemy.actor.Director

_actorsFinishedExecution, _currentTime, _finishRequested, _initializables, _stopRequested, timeResolution

Fields inherited from class ptolemy.kernel.util.NamedObj

_changeListeners, _changeLock, _changeRequests, _debugging, _debugListeners, _elementName, _isPersistent, _verbose, _workspace, ATTRIBUTES, CLASSNAME, COMPLETE, CONTENTS, DEEP, FULLNAME, LINKS

Fields inherited from interface ptolemy.actor.Executable

COMPLETED, NOT_READY, STOP_ITERATING

Constructor Summary

CTMixedSignalDirector()
Construct a director in the default workspace with an empty string as its name.

CTMixedSignalDirector(CompositeEntity container, java.lang.String name)
Construct a director in the given container with the given name.

CTMixedSignalDirector(Workspace workspace)
Construct a director in the workspace with an empty name.

Method Summary

protected void	_initParameters() Initialize parameters in addition to the parameters inherited from CTMultiSolverDirector.
protected boolean	_isTopLevel() Return true if this is a top-level director.
protected void	_rollback() Rollback the system to a "known good" state.
void	attributeChanged(Attribute attribute) React to a change in an attribute.
boolean	canBeInsideDirector() Return true indicating that this director can be an inside director.
void	fire() Record the current model time as a known good time for roll back and call the super.fire() method.
void	initialize() Initialize the execution.
boolean	postfire() If this is not a top-level director, request a refiring at the current model time.
boolean	prefire() Always returns true, indicating that the (sub)system is always ready for one iteration.

Methods inherited from class ptolemy.domains.ct.kernel.CTMultiSolverDirector

_continuousPhaseExecution, _discretePhaseExecution, _isOutputAccurate, _isStateAccurate, _iterateEventGenerators, _iteratePurelyDiscreteActors, _iterateWaveformGenerators, _predictNextStepSize, _propagateResolvedStates, _refinedStepWRTOutput, _refinedStepWRTState, _removeCurrentTimeFromBreakpointTable, _resolveInitialStates, canBeTopLevelDirector, establishInitialStates, fireEventGenerators, getBreakpointSolver, getExecutiveCTGeneralDirector, getNormalODESolver, getODESolverClassName, hasCurrentEvent, postfireEventGenerators, preinitialize, produceOutput, setInitialStatesNotReady, setModelTime, updateContinuousStates

Methods inherited from class ptolemy.domains.ct.kernel.CTDirector

_instantiateODESolver, _setCurrentODESolver, _setDiscretePhase, _setExecutionPhase, _setIterationBeginTime, clone, delayDependency, fireAt, getBreakPoints, getCurrentODESolver, getCurrentStepSize, getErrorTolerance, getExecutionPhase, getInitialStepSize, getIterationBeginTime, getMaxIterations, getMaxStepSize, getMinStepSize, getModelNextIterationTime, getModelStartTime, getModelStopTime, getSuggestedNextStepSize, getValueResolution, isDiscretePhase, newReceiver, prefireClear, prefireDynamicActors, setCurrentStepSize, setSuggestedNextStepSize, suggestedModalModelDirectors

Methods inherited from class ptolemy.actor.sched.StaticSchedulingDirector

_setScheduler, addDebugListener, getScheduler, invalidateSchedule, isScheduleValid, removeDebugListener, setScheduler

Methods inherited from class ptolemy.actor.Director

_description, _fireContainerAt, _isEmbedded, _transferInputs, _transferOutputs, addInitializable, createSchedule, defaultDependency, finish, fireAt, fireAtCurrentTime, getCausalityInterface, getCurrentTime, getGlobalTime, getModelTime, getNextIterationTime, getStartTime, getStopTime, getTimeResolution, implementsStrictActorSemantics, initialize, invalidateResolvedTypes, isFireFunctional, isStopRequested, isStrict, iterate, preinitialize, removeInitializable, requestInitialization, setContainer, setCurrentTime, stop, stopFire, supportMultirateFiring, terminate, transferInputs, transferOutputs, wrapup

Methods inherited from class ptolemy.kernel.util.Attribute

_checkContainer, _getContainedObject, _propagateExistence, getContainer, moveDown, moveToFirst, moveToIndex, moveToLast, moveUp, setName, updateContent

Methods inherited from class ptolemy.kernel.util.NamedObj

_addAttribute, _adjustOverride, _attachText, _cloneFixAttributeFields, _debug, _debug, _debug, _debug, _debug, _exportMoMLContents, _getIndentPrefix, _isMoMLSuppressed, _markContentsDerived, _propagateValue, _recordDecoratedAttributes, _removeAttribute, _splitName, _stripNumericSuffix, _validateSettables, addChangeListener, attributeList, attributeList, attributeTypeChanged, clone, containedObjectsIterator, deepContains, depthInHierarchy, description, description, event, executeChangeRequests, exportMoML, exportMoML, exportMoML, exportMoML, exportMoML, exportMoMLPlain, getAttribute, getAttribute, getAttributes, getChangeListeners, getClassName, getDecoratorAttribute, getDecoratorAttributes, getDerivedLevel, getDerivedList, getDisplayName, getElementName, getFullName, getModelErrorHandler, getName, getName, getPrototypeList, getSource, handleModelError, isDeferringChangeRequests, isOverridden, isPersistent, lazyContainedObjectsIterator, message, propagateExistence, propagateValue, propagateValues, removeChangeListener, requestChange, setClassName, setDeferringChangeRequests, setDerivedLevel, setDisplayName, setModelErrorHandler, setPersistent, setSource, sortContainedObjects, toplevel, toString, uniqueName, validateSettables, workspace

Methods inherited from class java.lang.Object

equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Methods inherited from interface ptolemy.actor.TimedDirector

getModelTime, getTimeResolution

Field Detail

runAheadLength

public Parameter runAheadLength

Parameter of the run ahead length. The default value is 1.0.

_isTop

private boolean _isTop

_knownGoodTime

private Time _knownGoodTime

_mutationVersion

private long _mutationVersion

_outsideTime

private Time _outsideTime

_runAheadLength

private double _runAheadLength

Constructor Detail

CTMixedSignalDirector

public CTMixedSignalDirector()

Construct a director in the default workspace with an empty string as its name. The director is added to the list of objects in the workspace. Increment the version number of the workspace. All the parameters take their default values.

CTMixedSignalDirector

public CTMixedSignalDirector(Workspace workspace)

Construct a director in the workspace with an empty name. The director is added to the list of objects in the workspace. Increment the version number of the workspace. All the parameters take their default values.

Parameters:

workspace - The workspace of this object.

CTMixedSignalDirector

public CTMixedSignalDirector(CompositeEntity container,
                             java.lang.String name)
                      throws IllegalActionException,
                             NameDuplicationException

Construct a director in the given container with the given name. The container argument must not be null, or a NullPointerException will be thrown. If the name argument is null, then the name is set to the empty string. Increment the version number of the workspace. All the parameters take their default values.

Parameters:

container - The container.

name - Name of this director.

Throws:

IllegalActionException - If the director is not compatible with the specified container. May be thrown in a derived class.

NameDuplicationException - If the container is not a CompositeActor and the name collides with an entity in the container.

Method Detail

attributeChanged

public void attributeChanged(Attribute attribute)
                      throws IllegalActionException

React to a change in an attribute. If the changed attribute matches a parameter of the director, then the corresponding private copy of the parameter value will be updated.

Overrides:

attributeChanged in class CTMultiSolverDirector

Parameters:

attribute - The changed attribute.

Throws:

IllegalActionException - If the runAhendLength does not have a valid token, or the superclass throws it.

canBeInsideDirector

public boolean canBeInsideDirector()

Return true indicating that this director can be an inside director.

Overrides:

canBeInsideDirector in class CTMultiSolverDirector

Returns:

True always.

fire

public void fire()
          throws IllegalActionException

Record the current model time as a known good time for roll back and call the super.fire() method.

Specified by:

fire in interface Executable

Overrides:

fire in class CTMultiSolverDirector

Throws:

IllegalActionException - If thrown by the super class.

initialize

public void initialize()
                throws IllegalActionException

Initialize the execution. If this director is not at the top level, ask the executive director to fire the container of this director at the current model time.

Specified by:

initialize in interface Initializable

Overrides:

initialize in class CTMultiSolverDirector

Throws:

IllegalActionException - If thrown by the initialize method of super class, or the quest for refiring can not be accepted, or if the director does not agree to fire the actor at the specified time.

See Also:

CTMultiSolverDirector.initialize()

postfire

public boolean postfire()
                 throws IllegalActionException

If this is not a top-level director, request a refiring at the current model time. Otherwise, behave exactly as a CTMultiSolverDirector.

Specified by:

postfire in interface Executable

Overrides:

postfire in class CTMultiSolverDirector

Returns:

True if the simulation is not finished.

Throws:

IllegalActionException - If thrown in the postfire method in the super class or the refiring can not be granted, or if the director does not agree to fire the actor at the specified time.

prefire

public boolean prefire()
                throws IllegalActionException

Always returns true, indicating that the (sub)system is always ready for one iteration.

If this is not a top-level director, some additional work is done to synchronize time with the executive director. In particular, it will compare its local time, say t, with the current time of the executive director, say t0.
If t == t0, do nothing.

If t > t0, then rollback to the "known good" time (which should be less than the outside time).

If t < t0, then throw an exception because the CT subsystem should always run ahead of the outside event-based system.

If this director is not a top-level director, the iteration end time is resolved from the current time of the outside system, say t1, the next iteration time of the outside system, say t2, and the runAheadLength parameter of this director, say t3. The iteration end time is set to be t5 = t1 + min(t2, t3). The iteration end time may be further refined in the fire() method due to possible event generated during the iteration. In particular, when the first event is detected, say at t5 and t5 < t4, then the iteration ends at t5.

This method updates the suggested step size.

Specified by:

prefire in interface Executable

Overrides:

prefire in class CTMultiSolverDirector

Returns:

true Always.

Throws:

IllegalActionException - If the local time is less than the current time of the executive director, or thrown by a directed actor.

_initParameters

protected void _initParameters()

Initialize parameters in addition to the parameters inherited from CTMultiSolverDirector. In this class the additional parameter is the maximum run ahead time length (runAheadLength). The default value is 1.0.

Overrides:

_initParameters in class CTMultiSolverDirector

_isTopLevel

protected final boolean _isTopLevel()

Return true if this is a top-level director.

Overrides:

_isTopLevel in class Director

Returns:

True if this director is at the top level.

_rollback

protected void _rollback()
                  throws IllegalActionException

Rollback the system to a "known good" state. All the actors with states are called to restore their saved states. The current time of the director is set to the time of the "known good" state.

Throws:

IllegalActionException - If thrown by the goToMarkedState() method of an actor, or the schedule does not exist.