SI Estimate AR Model VI

System Identification VIs

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SI Estimate AR Model VI

Owning Palette: Polynomial Model Estimation VIs

Installed With: System Identification Toolkit

Estimates the parameters of an AR model for an unknown system. Wire data to the response signal input to determine the polymorphic instance to use or manually select the instance.

Details  

Use the pull-down menu to select an instance of this VI.

 Place on the block diagram  Find on the Functions palette

SI Estimate AR Model (Waveform)

principle component level (%) defines the percentage of principle components this VI uses. This parameter applies only when method is Principal Component.
response signal is the input waveform of the response signal. The length of response signal must be greater than two times order of AR model.
order of AR model specifies the order of the AR model. The value of order of AR model must be greater than or equal to 0.
method specifies the method to use to estimate the AR model.

0Forward-Backward (default)
1Least-Squares
2Yule-Walker
3Burg-Lattice
4Principal Component
error in describes error conditions that occur before this VI or function runs. The default is no error. If an error occurred before this VI or function runs, the VI or function passes the error in value to error out. This VI or function runs normally only if no error occurred before this VI or function runs. If an error occurs while this VI or function runs, it runs normally and sets its own error status in error out. Use the Simple Error Handler or General Error Handler VIs to display the description of the error code. Use error in and error out to check errors and to specify execution order by wiring error out from one node to error in of the next node.
status is TRUE (X) if an error occurred before this VI or function ran or FALSE (checkmark) to indicate a warning or that no error occurred before this VI or function ran. The default is FALSE.
code is the error or warning code. The default is 0. If status is TRUE, code is a nonzero error code. If status is FALSE, code is 0 or a warning code.
source specifies the origin of the error or warning and is, in most cases, the name of the VI or function that produced the error or warning. The default is an empty string.
system model out returns information about the model structure, nominal or estimated parameters, identification result, and so on. Use the Model Management VIs to retrieve the information system model out contains.
Note  You can use a customized system model probe to view model information that flows through system model wires when you debug a block diagram created with the System Identification VIs. Right-click a system model wire and select Custom Probe»SI System Model from the shortcut menu to use the system model probe.
coefficients of AR model returns the coefficients of the AR model.
noise returns the disturbance e(t) in the estimated system model.
error out contains error information. If error in indicates that an error occurred before this VI or function ran, error out contains the same error information. Otherwise, it describes the error status that this VI or function produces. Right-click the error out front panel indicator and select Explain Error from the shortcut menu for more information about the error.
status is TRUE (X) if an error occurred or FALSE (checkmark) to indicate a warning or that no error occurred.
code is the error or warning code. If status is TRUE, code is a nonzero error code. If status is FALSE, code is 0 or a warning code.
source describes the origin of the error or warning and is, in most cases, the name of the VI or function that produced the error or warning.

SI Estimate AR Model (Array)

principle component level (%) defines the percentage of principle components this VI uses. This parameter applies only when method is Principal Component.
response signal is the input array of the response signal. The length of response signal must be greater than two times order of AR model.
order of AR model specifies the order of the AR model. The value of order of AR model must be greater than or equal to 0.
method specifies the method to use to estimate the AR model.

0Forward-Backward (default)
1Least-Squares
2Yule-Walker
3Burg-Lattice
4Principal Component
error in describes error conditions that occur before this VI or function runs. The default is no error. If an error occurred before this VI or function runs, the VI or function passes the error in value to error out. This VI or function runs normally only if no error occurred before this VI or function runs. If an error occurs while this VI or function runs, it runs normally and sets its own error status in error out. Use the Simple Error Handler or General Error Handler VIs to display the description of the error code. Use error in and error out to check errors and to specify execution order by wiring error out from one node to error in of the next node.
status is TRUE (X) if an error occurred before this VI or function ran or FALSE (checkmark) to indicate a warning or that no error occurred before this VI or function ran. The default is FALSE.
code is the error or warning code. The default is 0. If status is TRUE, code is a nonzero error code. If status is FALSE, code is 0 or a warning code.
source specifies the origin of the error or warning and is, in most cases, the name of the VI or function that produced the error or warning. The default is an empty string.
sampling rate specifies the sampling frequency in hertz. The value of sampling rate must be greater than 0. sampling rate is ignored if the response signal is a waveforms data file.
system model out returns information about the model structure, nominal or estimated parameters, identification result, and so on. Use the Model Management VIs to retrieve the information system model out contains.
Note  You can use a customized system model probe to view model information that flows through system model wires when you debug a block diagram created with the System Identification VIs. Right-click a system model wire and select Custom Probe»SI System Model from the shortcut menu to use the system model probe.
coefficients of AR model returns the coefficients of the AR model.
noise returns the disturbance e(t) in the estimated system model.
error out contains error information. If error in indicates that an error occurred before this VI or function ran, error out contains the same error information. Otherwise, it describes the error status that this VI or function produces. Right-click the error out front panel indicator and select Explain Error from the shortcut menu for more information about the error.
status is TRUE (X) if an error occurred or FALSE (checkmark) to indicate a warning or that no error occurred.
code is the error or warning code. If status is TRUE, code is a nonzero error code. If status is FALSE, code is 0 or a warning code.
source describes the origin of the error or warning and is, in most cases, the name of the VI or function that produced the error or warning.

SI Estimate AR Model Details

Refer to the LabVIEW System Identification Toolkit Algorithm References manual for more information about the forward-backward, least-squares, Yule-Walker, Burg-Lattice, and principal component methods.

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