ptolemy.domains.ct.lib
Class LevelCrossingDetector

java.lang.Object
  ptolemy.kernel.util.NamedObj
      ptolemy.kernel.InstantiableNamedObj
          ptolemy.kernel.Entity
              ptolemy.kernel.ComponentEntity
                  ptolemy.actor.AtomicActor
                      ptolemy.actor.TypedAtomicActor
                          ptolemy.domains.ct.lib.LevelCrossingDetector

All Implemented Interfaces:

java.io.Serializable, java.lang.Cloneable, Actor, Executable, FiringsRecordable, Initializable, TypedActor, CTEventGenerator, CTStepSizeControlActor, Changeable, Debuggable, DebugListener, Derivable, Instantiable, ModelErrorHandler, MoMLExportable, Moveable, Nameable

Direct Known Subclasses:

ZeroCrossingDetector

public class LevelCrossingDetector
extends TypedAtomicActor
implements CTStepSizeControlActor, CTEventGenerator

An event detector that converts continuous signals to discrete events when the continuous signal crosses a level threshold.

The direction parameter can constrain the actor to detect only rising or falling transitions. It has three possible values, "rising", "falling", and "both", where "both" is the default.

When the trigger equals the level threshold (within the specified errorTolerance), this actor outputs a discrete event with value defaultEventValue if useEventValue is selected. Otherwise, the actor outputs a discrete event with the value as the level threshold.

This actor controls the step size such that level crossings never occur during an integration. So, this actor is only used in Continuous-Time domain.

Since:

Ptolemy II 2.0

Version:

$Id: LevelCrossingDetector.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.Entity

Entity.ContainedObjectsIterator

Field Summary

private boolean	_detectFallingCrossing
private boolean	_detectRisingCrossing
private double	_errorTolerance
private boolean	_eventMissed
private boolean	_eventNow
private double	_lastTrigger
protected double	_level The level threshold this actor detects.
private double	_thisTrigger
Parameter	defaultEventValue A parameter that specifies the value of output events if the useEventValue parameter is checked.
StringParameter	direction A parameter that can be used to limit the detected level crossings to rising or falling.
Parameter	errorTolerance The parameter of error tolerance of type double.
Parameter	level The parameter that specifies the level threshold.
TypedIOPort	output The output port.
TypedIOPort	trigger The trigger port.
Parameter	useDefaultEventValue The parameter that indicates whether to use the default event value.

Fields inherited from class ptolemy.actor.AtomicActor

_actorFiringListeners, _initializables, _notifyingActorFiring, _stopRequested

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

Fields inherited from interface ptolemy.actor.Executable

COMPLETED, NOT_READY, STOP_ITERATING

Constructor Summary

LevelCrossingDetector(CompositeEntity container, java.lang.String name)
Construct an actor in the specified container with the specified name.

Method Summary

void	attributeChanged(Attribute attribute) Update the attribute if it has been changed.
java.lang.Object	clone(Workspace workspace) Clone the actor into the specified workspace.
void	fire() Produce a discrete event if level crossing happens.
boolean	hasCurrentEvent() Return true if there is an event at the current time.
void	initialize() Initialize the execution.
boolean	isOutputAccurate() Return true if there is no event detected during the current step size.
boolean	isStateAccurate() Always return true because this actor is not involved in resolving states.
boolean	postfire() Prepare for the next iteration, by making the current trigger token to be the history trigger token.
double	predictedStepSize() Return the maximum Double, since this actor does not predict step size.
void	preinitialize() Make sure the actor runs inside a CT domain.
double	refinedStepSize() Return the refined step size if there is a missed event, otherwise return the current step size.

Methods inherited from class ptolemy.actor.TypedAtomicActor

_addPort, _fireAt, _fireAt, attributeTypeChanged, clone, newPort, typeConstraintList, typeConstraints

Methods inherited from class ptolemy.actor.AtomicActor

_actorFiring, _actorFiring, addActorFiringListener, addInitializable, connectionsChanged, createReceivers, declareDelayDependency, getCausalityInterface, getDirector, getExecutiveDirector, getManager, inputPortList, isFireFunctional, isStrict, iterate, newReceiver, outputPortList, prefire, pruneDependencies, recordFiring, removeActorFiringListener, removeDependency, removeInitializable, setContainer, stop, stopFire, terminate, wrapup

Methods inherited from class ptolemy.kernel.ComponentEntity

_adjustDeferrals, _checkContainer, _getContainedObject, _propagateExistence, getContainer, instantiate, isAtomic, isOpaque, moveDown, moveToFirst, moveToIndex, moveToLast, moveUp, propagateExistence, setName

Methods inherited from class ptolemy.kernel.Entity

_description, _exportMoMLContents, _removePort, _validateSettables, connectedPortList, connectedPorts, containedObjectsIterator, getAttribute, getPort, getPorts, linkedRelationList, linkedRelations, portList, removeAllPorts, setClassDefinition, uniqueName

Methods inherited from class ptolemy.kernel.InstantiableNamedObj

_setParent, exportMoML, getChildren, getElementName, getParent, getPrototypeList, isClassDefinition, isWithinClassDefinition

Methods inherited from class ptolemy.kernel.util.NamedObj

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

Methods inherited from class java.lang.Object

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

Methods inherited from interface ptolemy.actor.Actor

createReceivers, getCausalityInterface, getDirector, getExecutiveDirector, getManager, inputPortList, newReceiver, outputPortList

Methods inherited from interface ptolemy.actor.Executable

isFireFunctional, isStrict, iterate, prefire, stop, stopFire, terminate

Methods inherited from interface ptolemy.actor.Initializable

addInitializable, removeInitializable, wrapup

Methods inherited from interface ptolemy.kernel.util.Nameable

description, getContainer, getDisplayName, getFullName, getName, getName, setName

Methods inherited from interface ptolemy.actor.Actor

createReceivers, getCausalityInterface, getDirector, getExecutiveDirector, getManager, inputPortList, newReceiver, outputPortList

Methods inherited from interface ptolemy.actor.Executable

isFireFunctional, isStrict, iterate, prefire, stop, stopFire, terminate

Methods inherited from interface ptolemy.actor.Initializable

addInitializable, removeInitializable, wrapup

Methods inherited from interface ptolemy.kernel.util.Nameable

description, getContainer, getDisplayName, getFullName, getName, getName, setName

Methods inherited from interface ptolemy.kernel.util.Derivable

getDerivedLevel, getDerivedList, propagateValue

Field Detail

defaultEventValue

public Parameter defaultEventValue

A parameter that specifies the value of output events if the useEventValue parameter is checked. By default, it contains a DoubleToken of 0.0.

direction

public StringParameter direction

A parameter that can be used to limit the detected level crossings to rising or falling. There are three choices: "falling", "rising", and "both". The default value is "both".

errorTolerance

public Parameter errorTolerance

The parameter of error tolerance of type double. By default, it contains a DoubleToken of 1e-4.

level

public Parameter level

The parameter that specifies the level threshold. By default, it contains a DoubleToken of value 0.0. Note, a change of this parameter at run time will not be applied until the next iteration.

output

public TypedIOPort output

The output port. The type is at least the type of the defaultEventValue parameter.

trigger

public TypedIOPort trigger

The trigger port. Single port with type double.

useDefaultEventValue

public Parameter useDefaultEventValue

The parameter that indicates whether to use the default event value.

_level

protected double _level

The level threshold this actor detects.

_detectRisingCrossing

private boolean _detectRisingCrossing

_detectFallingCrossing

private boolean _detectFallingCrossing

_errorTolerance

private double _errorTolerance

_eventMissed

private boolean _eventMissed

_eventNow

private boolean _eventNow

_lastTrigger

private double _lastTrigger

_thisTrigger

private double _thisTrigger

Constructor Detail

LevelCrossingDetector

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

Construct an actor in the specified container with the specified name. The name must be unique within the container or an exception is thrown. The container argument must not be null, or a NullPointerException will be thrown.

Parameters:

container - The subsystem that this actor is lived in

name - The actor's name

Throws:

IllegalActionException - If the entity cannot be contained by the proposed container.

NameDuplicationException - If name coincides with an entity already in the container.

Method Detail

attributeChanged

public void attributeChanged(Attribute attribute)
                      throws IllegalActionException

Update the attribute if it has been changed. If the attribute is errorTolerance or level, then update the local cache.

Overrides:

attributeChanged in class NamedObj

Parameters:

attribute - The attribute that has changed.

Throws:

IllegalActionException - If the attribute change failed.

clone

public java.lang.Object clone(Workspace workspace)
                       throws java.lang.CloneNotSupportedException

Clone the actor into the specified workspace. This calls the base class and then sets the value public variable in the new object to equal the cloned parameter in that new object.

Overrides:

clone in class AtomicActor

Parameters:

workspace - The workspace for the new object.

Returns:

A new actor.

Throws:

java.lang.CloneNotSupportedException - If a derived class contains an attribute that cannot be cloned.

See Also:

NamedObj.exportMoML(Writer, int, String), NamedObj.setDeferringChangeRequests(boolean)

fire

public void fire()
          throws IllegalActionException

Produce a discrete event if level crossing happens. If the current execution is in a continuous phase, the current trigger is recorded but no event can be produced. If the current execution is in a discrete phase, the current and previous trigger tokens are compared to find whether a level crossing happens. If there is a crossing, a discrete event is generated.

The value of this event may be the specified level, or the default event value if the usingDefaultEventValue is configured true (checked).

Specified by:

fire in interface Executable

Overrides:

fire in class AtomicActor

Throws:

IllegalActionException - If can not get token from the trigger port or can not send token through the output port.

hasCurrentEvent

public boolean hasCurrentEvent()

Return true if there is an event at the current time.

Specified by:

hasCurrentEvent in interface CTEventGenerator

Returns:

True if there is an event at the current time.

initialize

public void initialize()
                throws IllegalActionException

Initialize the execution.

Specified by:

initialize in interface Initializable

Overrides:

initialize in class AtomicActor

Throws:

IllegalActionException - If thrown by the super class.

isOutputAccurate

public boolean isOutputAccurate()

Return true if there is no event detected during the current step size.

Specified by:

isOutputAccurate in interface CTStepSizeControlActor

Returns:

True if there is no event detected in the current iteration.

isStateAccurate

public boolean isStateAccurate()

Always return true because this actor is not involved in resolving states.

Specified by:

isStateAccurate in interface CTStepSizeControlActor

Returns:

true.

postfire

public boolean postfire()
                 throws IllegalActionException

Prepare for the next iteration, by making the current trigger token to be the history trigger token.

Specified by:

postfire in interface Executable

Overrides:

postfire in class AtomicActor

Returns:

True always.

Throws:

IllegalActionException - If thrown by the super class.

predictedStepSize

public double predictedStepSize()

Return the maximum Double, since this actor does not predict step size.

Specified by:

predictedStepSize in interface CTStepSizeControlActor

Returns:

java.Double.MAX_VALUE.

preinitialize

public void preinitialize()
                   throws IllegalActionException

Make sure the actor runs inside a CT domain.

Specified by:

preinitialize in interface Initializable

Overrides:

preinitialize in class AtomicActor

Throws:

IllegalActionException - If the director is not a CTDirector or the parent class throws it.

refinedStepSize

public double refinedStepSize()

Return the refined step size if there is a missed event, otherwise return the current step size.

Specified by:

refinedStepSize in interface CTStepSizeControlActor

Returns:

The refined step size.