ptolemy.actor.lib
Class MovingAverage

java.lang.Object
  ptolemy.kernel.util.NamedObj
      ptolemy.kernel.InstantiableNamedObj
          ptolemy.kernel.Entity
              ptolemy.kernel.ComponentEntity
                  ptolemy.actor.AtomicActor
                      ptolemy.actor.TypedAtomicActor
                          ptolemy.actor.lib.Transformer
                              ptolemy.actor.lib.MovingAverage

All Implemented Interfaces:

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

public class MovingAverage
extends Transformer

This actor outputs the moving average of the input sequence. The maximum number of prior inputs to be averaged is given by the maxPastInputsToAverage parameter. The output is the average of the all the previous inputs that have been received if fewer than maxPastInputsToAverage have been received, and the average of the previous maxPastInputsToAverage inputs otherwise. The input can be any data type that supports division by a double.

Since:

Ptolemy II 6.1

Version:

$Id: MovingAverage.java,v 1.4 2007/12/06 21:56:30 cxh Exp $

Author:

Edward A. Lee

See Also:

Token, Serialized Form

Accepted Rating:

Red (eal)

Proposed Rating:

Yellow (eal)

Nested Class Summary

Nested classes/interfaces inherited from class ptolemy.kernel.Entity

Entity.ContainedObjectsIterator

Field Summary

protected int	_count Count of the number of inputs received, bounded by the size of the _data array.
protected Token[]	_data The delay line.
protected int	_maxPastInputsToAverage Maximum number of past inputs to average.
protected int	_mostRecent The index into the delay line of the most recent input.
protected boolean	_reinitializeNeeded Indicator that at least an attribute has been changed since the last initialization.
Parameter	maxPastInputsToAverage The maximum number of past inputs to average.

Fields inherited from class ptolemy.actor.lib.Transformer

input, output

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

Constructor Summary

MovingAverage(CompositeEntity container, java.lang.String name)
Construct an actor with the given container and name.

Method Summary

protected void	_reinitialize() Reinitialize local variables in response to changes in attributes.
void	attributeChanged(Attribute attribute) Set a flag that causes recalculation of various local variables that are used in execution on the next invocation of fire().
void	fire() Consume the inputs and produce the output.
void	initialize() Perform domain-specific initialization by calling the initialize(Actor) method of the director.
boolean	prefire() Return false if the input does not have a token.

Methods inherited from class ptolemy.actor.TypedAtomicActor

_addPort, attributeTypeChanged, clone, newPort, typeConstraintList

Methods inherited from class ptolemy.actor.AtomicActor

_actorFiring, _actorFiring, _createReceivers, addActorFiringListener, addInitializable, clone, connectionsChanged, getDirector, getExecutiveDirector, getFunctionDependency, getManager, inputPortList, isFireFunctional, isStrict, iterate, newReceiver, outputPortList, postfire, preinitialize, 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, _removeAttribute, _splitName, _stripNumericSuffix, addChangeListener, addDebugListener, attributeList, attributeList, deepContains, depthInHierarchy, description, description, event, executeChangeRequests, exportMoML, exportMoML, exportMoML, exportMoML, exportMoMLPlain, getAttribute, getAttributes, getChangeListeners, getClassName, getDerivedLevel, getDerivedList, getDisplayName, getFullName, getModelErrorHandler, getName, getName, getSource, handleModelError, isDeferringChangeRequests, isOverridden, isPersistent, 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

getDirector, getExecutiveDirector, getFunctionDependency, getManager, inputPortList, newReceiver, outputPortList

Methods inherited from interface ptolemy.actor.Executable

isFireFunctional, isStrict, iterate, postfire, stop, stopFire, terminate

Methods inherited from interface ptolemy.actor.Initializable

addInitializable, preinitialize, 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

maxPastInputsToAverage

public Parameter maxPastInputsToAverage

The maximum number of past inputs to average. This is an integer that defaults to 10.

_data

protected Token[] _data

The delay line.

_mostRecent

protected int _mostRecent

The index into the delay line of the most recent input.

_count

protected int _count

Count of the number of inputs received, bounded by the size of the _data array.

_maxPastInputsToAverage

protected int _maxPastInputsToAverage

Maximum number of past inputs to average.

_reinitializeNeeded

protected boolean _reinitializeNeeded

Indicator that at least an attribute has been changed since the last initialization.

Constructor Detail

MovingAverage

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

Construct an actor with the given container and name.

Parameters:

container - The container.

name - The name of this actor.

Throws:

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

NameDuplicationException - If the container already has an actor with this name.

Method Detail

attributeChanged

public void attributeChanged(Attribute attribute)
                      throws IllegalActionException

Set a flag that causes recalculation of various local variables that are used in execution on the next invocation of fire().

Overrides:

attributeChanged in class NamedObj

Parameters:

attribute - The attribute that changed.

Throws:

IllegalActionException - If the attribute contains an invalid value or if the super method throws it.

fire

public void fire()
          throws IllegalActionException

Consume the inputs and produce the output.

Specified by:

fire in interface Executable

Overrides:

fire in class AtomicActor

Throws:

IllegalActionException - If parameter values are invalid, or if there is no director, or if runtime type conflicts occur.

prefire

public boolean prefire()
                throws IllegalActionException

Return false if the input does not have a token. Otherwise, return what the superclass returns.

Specified by:

prefire in interface Executable

Overrides:

prefire in class AtomicActor

Returns:

False if the number of input tokens available is not at least equal to the decimation parameter.

Throws:

IllegalActionException - If the superclass throws it.

initialize

public void initialize()
                throws IllegalActionException

Perform domain-specific initialization by calling the initialize(Actor) method of the director. The director may reject the actor by throwing an exception if the actor is incompatible with the domain. Set a flag that reinitializes the data buffer at the first firing.

Specified by:

initialize in interface Initializable

Overrides:

initialize in class AtomicActor

Throws:

IllegalActionException - If the superclass throws it.

_reinitialize

protected void _reinitialize()
                      throws IllegalActionException

Reinitialize local variables in response to changes in attributes.

Throws:

IllegalActionException - If there is a problem reinitializing.