ptolemy.domains.sdf.lib
Class DownSample

java.lang.Object
  ptolemy.kernel.util.NamedObj
      ptolemy.kernel.InstantiableNamedObj
          ptolemy.kernel.Entity
              ptolemy.kernel.ComponentEntity
                  ptolemy.actor.AtomicActor
                      ptolemy.actor.TypedAtomicActor
                          ptolemy.domains.sdf.lib.SDFTransformer
                              ptolemy.domains.sdf.lib.DownSample

All Implemented Interfaces:

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

public class DownSample
extends SDFTransformer

This actor downsamples an input stream by an integer factor by removing tokens. The downsample factor is given by the factor parameter. On each firing, this actor consumes factor tokens from the input and sends only one of them to the output. The one sent depends on the phase parameter. If phase is 0, then the most recent one (the last one consumed) is sent. If phase is 1, then the next most recent one is sent. The value of phase can range up to factor-1, in which case the first one consumed is sent. By default, the factor parameter is 2, so the input sample rate is twice that of the output. The default value for phase is 0.

This actor is data polymorphic. It can accept any token type on the input.

Since:

Ptolemy II 1.0

Version:

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

Author:

Steve Neuendorffer, Edward A. Lee

See Also:

UpSample, Serialized Form

Accepted Rating:

Yellow (neuendor)

Proposed Rating:

Yellow (neuendor)

Nested Class Summary

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

Entity.ContainedObjectsIterator

Field Summary

Parameter	factor The number of input tokens to read per output token produced.
Parameter	phase The phase of the output with respect to the input.

Fields inherited from class ptolemy.domains.sdf.lib.SDFTransformer

input, input_tokenConsumptionRate, output, output_tokenInitProduction, output_tokenProductionRate

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

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

Method Summary

void	attributeChanged(Attribute attribute) Ensure that the factor and phase parameters are both positive.
void	fire() Consume factor tokens from the input, and select one of them to send to the output based on the phase.

Methods inherited from class ptolemy.domains.sdf.lib.SDFTransformer

prefire

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, clone, connectionsChanged, createReceivers, declareDelayDependency, getCausalityInterface, getDirector, getExecutiveDirector, getManager, initialize, 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, _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, postfire, stop, stopFire, terminate

Methods inherited from interface ptolemy.actor.Initializable

addInitializable, initialize, 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

factor

public Parameter factor

The number of input tokens to read per output token produced. This is an integer that defaults to 2 and must be greater than zero.

phase

public Parameter phase

The phase of the output with respect to the input. This is an integer that defaults to 0 and must be between 0 and factor-1. If phase = 0, the most recent sample is the output, while if phase = factor-1 the oldest sample is the output.

Constructor Detail

DownSample

public DownSample(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

Ensure that the factor and phase parameters are both positive.

Overrides:

attributeChanged in class NamedObj

Parameters:

attribute - The attribute that has changed.

Throws:

IllegalActionException - If the parameters are out of range.

fire

public void fire()
          throws IllegalActionException

Consume factor tokens from the input, and select one of them to send to the output based on the phase.

Specified by:

fire in interface Executable

Overrides:

fire in class AtomicActor

Throws:

IllegalActionException - If there is no director, or if the phase value is out of range.