ptolemy.backtrack.automatic.ptolemy.domains.sdf.lib
Class Autocorrelation

java.lang.Object
  extended by ptolemy.kernel.util.NamedObj
      extended by ptolemy.kernel.InstantiableNamedObj
          extended by ptolemy.kernel.Entity
              extended by ptolemy.kernel.ComponentEntity
                  extended by ptolemy.actor.AtomicActor
                      extended by ptolemy.actor.TypedAtomicActor
                          extended by ptolemy.domains.sdf.lib.SDFTransformer
                              extended by ptolemy.backtrack.automatic.ptolemy.domains.sdf.lib.Autocorrelation
All Implemented Interfaces:
java.io.Serializable, java.lang.Cloneable, Actor, Executable, FiringsRecordable, Initializable, SequenceActor, TypedActor, Rollbackable, Changeable, Debuggable, DebugListener, Derivable, Instantiable, ModelErrorHandler, MoMLExportable, Moveable, Nameable

public class Autocorrelation
extends SDFTransformer
implements Rollbackable

This actor calculates the autocorrelation of a sequence of input tokens. It is polymorphic, supporting any input data type that supports multiplication, addition, and division by an integer. However, since integer division will lose the fractional portion of the result, type resolution will resolve the input type to double or double matrix if the input port is connected to an integer or integer matrix source, respectively.

Both biased and unbiased autocorrelation estimates are supported. If the parameter biased is true, then the autocorrelation estimate is

 N-1-k
 1  ---
 r(k) = -  \    x(n)x(n+k)
 N  /
 ---
 n=0
 
for k = 0, ... , p, where N is the number of inputs to average (numberOfInputs), p is the number of lags to estimate (numberOfLags), and x* is the conjugate of the input (if it is complex). This estimate is biased because the outermost lags have fewer than N terms in the summation, and yet the summation is still normalized by N.

If the parameter biased is false (the default), then the estimate is

 N-1-k
 1   ---
 r(k) = ---  \    x(n)x(n+k)
 N-k  /
 ---
 n=0
 
In this case, the estimate is unbiased. However, note that the unbiased estimate does not guarantee a positive definite sequence, so a power spectral estimate based on this autocorrelation estimate may have negative components.

The output will be an array of tokens whose type is at least that of the input. If the parameter symmetricOutput is true, then the output will be symmetric and have length equal to twice the number of lags requested plus one. Otherwise, the output will have length equal to twice the number of lags requested, which will be almost symmetric (insert the last sample into the first position to get the symmetric output that you would get with the symmetricOutput being true).

Since:
Ptolemy II 1.0
Version:
$Id: Autocorrelation.java 59167 2010-09-21 17:08:02Z cxh $
Author:
Edward A. Lee and Yuhong Xiong
See Also:
Serialized Form
Accepted Rating:
Yellow (neuendor)
Proposed Rating:
Green (eal)

Nested Class Summary
private static class Autocorrelation.FunctionTerm
           
private  class Autocorrelation.OutputTypeTerm
          Monotonic function that determines the type of the output port.
 
Nested classes/interfaces inherited from class ptolemy.kernel.Entity
Entity.ContainedObjectsIterator
 
Field Summary
private  int _lengthOfOutput
           
private  int _numberOfInputs
           
private  int _numberOfLags
           
private  Token[] _outputs
           
private  boolean _symmetricOutput
           
protected  Checkpoint $CHECKPOINT
           
private  FieldRecord $RECORD$_lengthOfOutput
           
private  FieldRecord $RECORD$_numberOfInputs
           
private  FieldRecord $RECORD$_numberOfLags
           
private  FieldRecord $RECORD$_outputs
           
private  FieldRecord $RECORD$_symmetricOutput
           
protected  CheckpointRecord $RECORD$$CHECKPOINT
           
private  FieldRecord[] $RECORDS
           
 Parameter biased
          If true, the estimate will be biased.
 Parameter numberOfInputs
          Number of input samples to average.
 Parameter numberOfLags
          Number of autocorrelation lags to output.
 Parameter symmetricOutput
          If true, then the output from each firing will have 2*numberOfLags + 1 samples (an odd number) whose values are symmetric about the midpoint.
 
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
Autocorrelation(CompositeEntity container, java.lang.String name)
          Construct an actor with the given container and name.
 
Method Summary
private  int $ASSIGN$_lengthOfOutput(int newValue)
           
private  int $ASSIGN$_numberOfInputs(int newValue)
           
private  int $ASSIGN$_numberOfLags(int newValue)
           
private  Token $ASSIGN$_outputs(int index0, Token newValue)
           
private  Token[] $ASSIGN$_outputs(Token[] newValue)
           
private  boolean $ASSIGN$_symmetricOutput(boolean newValue)
           
private  Token[] $BACKUP$_outputs()
           
 void $COMMIT(long timestamp)
          Commit changes up to the given timestamp, but not including changes made at timestamp and afterward.
 Checkpoint $GET$CHECKPOINT()
          Get the checkpoint object that monitors this rollbackable object.
 void $RESTORE(long timestamp, boolean trim)
          Restore a previous state to all the private fields of this rollbackable object.
 java.lang.Object $SET$CHECKPOINT(Checkpoint checkpoint)
          Set the checkpoint object of this rollbackable object.
 void attributeChanged(Attribute attribute)
          Check to see that the numberOfInputs parameter is positive, and that the numberOfLags parameter is positive.
 java.lang.Object clone(Workspace workspace)
          Clone the actor into the specified workspace.
 void fire()
          Consume tokens from the input and produce a token on the output that contains an array token that represents an autocorrelation estimate of the consumed tokens.
 boolean prefire()
          If there are not sufficient inputs, then return false.
 
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, 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

$CHECKPOINT

protected transient Checkpoint $CHECKPOINT

biased

public Parameter biased
If true, the estimate will be biased. This is a boolean with default value false.


numberOfInputs

public Parameter numberOfInputs
Number of input samples to average. This is an integer with default value 256.


numberOfLags

public Parameter numberOfLags
Number of autocorrelation lags to output. This is an integer with default value 64.


symmetricOutput

public Parameter symmetricOutput
If true, then the output from each firing will have 2*numberOfLags + 1 samples (an odd number) whose values are symmetric about the midpoint. If false, then the output from each firing will have 2*numberOfLags samples (an even number) by omitting one of the endpoints (the last one). This is a boolean with default value false.


_numberOfInputs

private int _numberOfInputs

_numberOfLags

private int _numberOfLags

_lengthOfOutput

private int _lengthOfOutput

_symmetricOutput

private boolean _symmetricOutput

_outputs

private Token[] _outputs

$RECORD$$CHECKPOINT

protected transient CheckpointRecord $RECORD$$CHECKPOINT

$RECORD$_numberOfInputs

private transient FieldRecord $RECORD$_numberOfInputs

$RECORD$_numberOfLags

private transient FieldRecord $RECORD$_numberOfLags

$RECORD$_lengthOfOutput

private transient FieldRecord $RECORD$_lengthOfOutput

$RECORD$_symmetricOutput

private transient FieldRecord $RECORD$_symmetricOutput

$RECORD$_outputs

private transient FieldRecord $RECORD$_outputs

$RECORDS

private transient FieldRecord[] $RECORDS
Constructor Detail

Autocorrelation

public Autocorrelation(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
Check to see that the numberOfInputs parameter is positive, and that the numberOfLags parameter is positive. Based on the new values, recompute the size of the output array.

Overrides:
attributeChanged in class NamedObj
Parameters:
attribute - The attribute that has changed.
Throws:
IllegalActionException - If the parameters are out of range.

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 type constraints.

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 has an attribute that cannot be cloned.
See Also:
NamedObj.exportMoML(Writer, int, String), NamedObj.setDeferringChangeRequests(boolean)

fire

public void fire()
          throws IllegalActionException
Consume tokens from the input and produce a token on the output that contains an array token that represents an autocorrelation estimate of the consumed tokens. The estimate is consistent with the parameters of the object, as described in the class comment.

Specified by:
fire in interface Executable
Overrides:
fire in class AtomicActor
Throws:
IllegalActionException - If there is no director.

prefire

public boolean prefire()
                throws IllegalActionException
If there are not sufficient inputs, then return false. Otherwise, return whatever the base class returns.

Specified by:
prefire in interface Executable
Overrides:
prefire in class SDFTransformer
Returns:
True if it is ok to continue.
Throws:
IllegalActionException - If the base class throws it.

$ASSIGN$_numberOfInputs

private final int $ASSIGN$_numberOfInputs(int newValue)

$ASSIGN$_numberOfLags

private final int $ASSIGN$_numberOfLags(int newValue)

$ASSIGN$_lengthOfOutput

private final int $ASSIGN$_lengthOfOutput(int newValue)

$ASSIGN$_symmetricOutput

private final boolean $ASSIGN$_symmetricOutput(boolean newValue)

$ASSIGN$_outputs

private final Token[] $ASSIGN$_outputs(Token[] newValue)

$ASSIGN$_outputs

private final Token $ASSIGN$_outputs(int index0,
                                     Token newValue)

$BACKUP$_outputs

private final Token[] $BACKUP$_outputs()

$COMMIT

public void $COMMIT(long timestamp)
Description copied from interface: Rollbackable
Commit changes up to the given timestamp, but not including changes made at timestamp and afterward.

Specified by:
$COMMIT in interface Rollbackable
Parameters:
timestamp - The timestamp.

$RESTORE

public void $RESTORE(long timestamp,
                     boolean trim)
Description copied from interface: Rollbackable
Restore a previous state to all the private fields of this rollbackable object.

Specified by:
$RESTORE in interface Rollbackable
Parameters:
timestamp - The timestamp taken at the time when the previous state was recorded.
trim - Whether to delete the records used for the rollback.
See Also:
Checkpoint.rollback(long, boolean)

$GET$CHECKPOINT

public final Checkpoint $GET$CHECKPOINT()
Description copied from interface: Rollbackable
Get the checkpoint object that monitors this rollbackable object.

Specified by:
$GET$CHECKPOINT in interface Rollbackable
Returns:
The checkpoint object.

$SET$CHECKPOINT

public final java.lang.Object $SET$CHECKPOINT(Checkpoint checkpoint)
Description copied from interface: Rollbackable
Set the checkpoint object of this rollbackable object. A merge operation is performed on the current checkpoint object and the new checkpoint object, so that the two checkpoint objects monitor the same set of objects when this function returns.

Specified by:
$SET$CHECKPOINT in interface Rollbackable
Parameters:
checkpoint - The new checkpoint object.
Returns:
This rollbackable object itself.
See Also:
Checkpoint.setCheckpoint(Checkpoint)