Class RecursiveLattice
- java.lang.Object
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- All Implemented Interfaces:
java.lang.Cloneable
,Actor
,Executable
,FiringsRecordable
,Initializable
,TypedActor
,Changeable
,Debuggable
,DebugListener
,Derivable
,Instantiable
,ModelErrorHandler
,MoMLExportable
,Moveable
,Nameable
- Direct Known Subclasses:
VariableRecursiveLattice
public class RecursiveLattice extends Transformer
A recursive (all-pole) filter with a lattice structure. The coefficients of such a filter are called "reflection coefficients." Recursive lattice filters are typically used as synthesis filters for random processes because it is easy to ensure that they are stable. A recursive lattice filter is stable if its reflection coefficients are all less than unity in magnitude. To get the reflection coefficients for a linear predictor for a particular random process, you can use the LevinsonDurbin actor. The inputs and outputs are of type double.The default reflection coefficients correspond to the following transfer function:
1 H(z) = -------------------------------------- 1 - 2z-1 + 1.91z-2 - 0.91z-3 + 0.205z-4
The structure of the filter is as follows:
y[0] y[1] y[n-1] y[n] X(n) ---(+)->--o-->----(+)->--o--->-- ... ->--(+)->--o--->---o---> Y(n) \ / \ / \ / | +Kn / +Kn-1 / +K1 / | X X X | -Kn \ -Kn-1 \ -K1 \ V / \ / \ / \ | (+)-<--o--[z]--(+)-<--o--[z]- ... -<--(+)-<--o--[z]--/ w[1] w[2] w[n]
where the [z] are unit delays and the (+) are adders and "y" and "w" are variables representing the state of the filter.The reflection (or partial-correlation (PARCOR)) coefficients should be specified right to left, K1 to Kn as above. Using exactly the same coefficients in the Lattice actor will result in precisely the inverse transfer function.
Note that the definition of reflection coefficients is not quite universal in the literature. The reflection coefficients in reference [2] are the negative of the ones used by this actor, which correspond to the definition in most other texts, and to the definition of partial-correlation (PARCOR) coefficients in the statistics literature. The signs of the coefficients used in this actor are appropriate for values given by the LevinsonDurbin actor.
References
[1] J. Makhoul, "Linear Prediction: A Tutorial Review", Proc. IEEE, Vol. 63, pp. 561-580, Apr. 1975.
[2] S. M. Kay, Modern Spectral Estimation: Theory & Application, Prentice-Hall, Englewood Cliffs, NJ, 1988.
- Since:
- Ptolemy II 1.0
- Version:
- $Id$
- Author:
- Edward A. Lee, Christopher Hylands, Steve Neuendorffer
- See Also:
IIR
,LevinsonDurbin
,Lattice
,VariableRecursiveLattice
- Pt.AcceptedRating:
- Yellow (cxh)
- Pt.ProposedRating:
- Yellow (cxh)
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Nested Class Summary
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Nested classes/interfaces inherited from class ptolemy.kernel.Entity
Entity.ContainedObjectsIterator
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Field Summary
Fields Modifier and Type Field Description Parameter
reflectionCoefficients
The reflection coefficients.-
Fields inherited from class ptolemy.actor.lib.Transformer
input, output
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Fields inherited from class ptolemy.actor.TypedAtomicActor
_typesValid
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Fields inherited from class ptolemy.actor.AtomicActor
_actorFiringListeners, _initializables, _notifyingActorFiring, _stopRequested
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Fields inherited from class ptolemy.kernel.util.NamedObj
_changeListeners, _changeLock, _changeRequests, _debugging, _debugListeners, _deferChangeRequests, _elementName, _isPersistent, _verbose, _workspace, ATTRIBUTES, CLASSNAME, COMPLETE, CONTENTS, DEEP, FULLNAME, LINKS
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Fields inherited from interface ptolemy.actor.Executable
COMPLETED, NOT_READY, STOP_ITERATING
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Constructor Summary
Constructors Constructor Description RecursiveLattice(CompositeEntity container, java.lang.String name)
Construct an actor with the given container and name.
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Method Summary
All Methods Instance Methods Concrete Methods Modifier and Type Method Description void
attributeChanged(Attribute attribute)
If the argument is the reflectionCoefficients parameter, then reallocate the arrays to use.java.lang.Object
clone(Workspace workspace)
Clone the actor into the specified workspace.void
fire()
Consume one input token, if there is one, and produce one output token.void
initialize()
Initialize the state of the filter.boolean
postfire()
Update the backward and forward prediction errors that were generated in fire() method.boolean
prefire()
Check to see if this actor is ready to fire.-
Methods inherited from class ptolemy.actor.TypedAtomicActor
_containedTypeConstraints, _customTypeConstraints, _defaultTypeConstraints, _fireAt, _fireAt, attributeTypeChanged, clone, isBackwardTypeInferenceEnabled, newPort, typeConstraintList, typeConstraints
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Methods inherited from class ptolemy.actor.AtomicActor
_actorFiring, _actorFiring, _declareDelayDependency, addActorFiringListener, addInitializable, connectionsChanged, createReceivers, declareDelayDependency, getCausalityInterface, getDirector, getExecutiveDirector, getManager, inputPortList, isFireFunctional, isStrict, iterate, newReceiver, outputPortList, preinitialize, pruneDependencies, recordFiring, removeActorFiringListener, removeDependency, removeInitializable, setContainer, stop, stopFire, terminate, wrapup
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Methods inherited from class ptolemy.kernel.ComponentEntity
_adjustDeferrals, _checkContainer, _getContainedObject, _propagateExistence, getContainer, instantiate, isAtomic, isOpaque, moveDown, moveToFirst, moveToIndex, moveToLast, moveUp, propagateExistence, setName
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Methods inherited from class ptolemy.kernel.Entity
_addPort, _description, _exportMoMLContents, _removePort, _validateSettables, connectedPortList, connectedPorts, containedObjectsIterator, getAttribute, getPort, getPorts, linkedRelationList, linkedRelations, portList, removeAllPorts, setClassDefinition, uniqueName
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Methods inherited from class ptolemy.kernel.InstantiableNamedObj
_setParent, exportMoML, getChildren, getElementName, getParent, getPrototypeList, isClassDefinition, isWithinClassDefinition
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Methods inherited from class ptolemy.kernel.util.NamedObj
_addAttribute, _adjustOverride, _attachText, _cloneFixAttributeFields, _containedDecorators, _copyChangeRequestList, _debug, _debug, _debug, _debug, _debug, _executeChangeRequests, _getIndentPrefix, _isMoMLSuppressed, _markContentsDerived, _notifyHierarchyListenersAfterChange, _notifyHierarchyListenersBeforeChange, _propagateValue, _removeAttribute, _splitName, _stripNumericSuffix, addChangeListener, addDebugListener, addHierarchyListener, attributeDeleted, attributeList, attributeList, decorators, 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, notifyOfNameChange, propagateValue, propagateValues, removeAttribute, removeChangeListener, removeDebugListener, removeHierarchyListener, requestChange, setClassName, setDeferringChangeRequests, setDerivedLevel, setDisplayName, setModelErrorHandler, setPersistent, setSource, sortContainedObjects, toplevel, toString, validateSettables, workspace
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Methods inherited from class java.lang.Object
equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait
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Methods inherited from interface ptolemy.actor.Actor
createReceivers, getCausalityInterface, getDirector, getExecutiveDirector, getManager, inputPortList, newReceiver, outputPortList
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Methods inherited from interface ptolemy.kernel.util.Derivable
getDerivedLevel, getDerivedList, propagateValue
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Methods inherited from interface ptolemy.actor.Executable
isFireFunctional, isStrict, iterate, stop, stopFire, terminate
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Methods inherited from interface ptolemy.actor.Initializable
addInitializable, preinitialize, removeInitializable, wrapup
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Methods inherited from interface ptolemy.kernel.util.Nameable
description, getContainer, getDisplayName, getFullName, getName, getName, setName
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Field Detail
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reflectionCoefficients
public Parameter reflectionCoefficients
The reflection coefficients. This is an array of doubles with default value {0.804534, -0.820577, 0.521934, -0.205}. These are the reflection coefficients for the linear predictor of a particular random process.
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Constructor Detail
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RecursiveLattice
public RecursiveLattice(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.
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Method Detail
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attributeChanged
public void attributeChanged(Attribute attribute) throws IllegalActionException
If the argument is the reflectionCoefficients parameter, then reallocate the arrays to use.- Overrides:
attributeChanged
in classNamedObj
- Parameters:
attribute
- The attribute that changed.- Throws:
IllegalActionException
- If the base class throws it.
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clone
public java.lang.Object clone(Workspace workspace) throws java.lang.CloneNotSupportedException
Clone the actor into the specified workspace.- Overrides:
clone
in classTypedAtomicActor
- 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)
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fire
public void fire() throws IllegalActionException
Consume one input token, if there is one, and produce one output token. If there is no input, then produce no output.- Specified by:
fire
in interfaceExecutable
- Overrides:
fire
in classAtomicActor<TypedIOPort>
- Throws:
IllegalActionException
- If there is no director.
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initialize
public void initialize() throws IllegalActionException
Initialize the state of the filter.- Specified by:
initialize
in interfaceInitializable
- Overrides:
initialize
in classAtomicActor<TypedIOPort>
- Throws:
IllegalActionException
- If a derived class throws it.
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postfire
public boolean postfire() throws IllegalActionException
Update the backward and forward prediction errors that were generated in fire() method.- Specified by:
postfire
in interfaceExecutable
- Overrides:
postfire
in classAtomicActor<TypedIOPort>
- Returns:
- False if the number of iterations matches the number requested.
- Throws:
IllegalActionException
- If there is no director.
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prefire
public boolean prefire() throws IllegalActionException
Check to see if this actor is ready to fire.- Specified by:
prefire
in interfaceExecutable
- Overrides:
prefire
in classAtomicActor<TypedIOPort>
- Returns:
- True if this actor is ready for firing, false otherwise.
- Throws:
IllegalActionException
- If there is no director.
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