IIR Cascade Filter VI

Owning Palette: Advanced IIR Filtering VIs

Requires: Full Development System

Filters the input sequence X using the cascade form of the IIR filter specified by the IIR Filter Cluster. Wire data to the X input to determine the polymorphic instance to use or manually select the instance.

Details  Example

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

Select an instance IIR Cascade Filter (DBL)IIR Cascade Filter (CDB)

Add to the block diagram

Find on the palette

IIR Cascade Filter (DBL)

	X is the input array of samples to filter.
	IIR Filter Cluster contains the cascaded form of IIR filter coefficients. This cluster is the output from one of the IIR coefficient design VIs: Butterworth Coefficients, Bessel Coefficients, Chebyshev Coefficients, Elliptic Coefficients, or Inv Chebyshev Coefficients. filter structure selects IIR second-order or fourth-order filter stages. 0 IIR 2nd Order 1 IIR 4th Order Reverse Coefficients is the reverse coefficients of the IIR cascade filter. Forward Coefficients is the forward coefficients of the IIR cascade filter.
	init/cont controls the initialization of the internal states. The default is FALSE. The first time this VI runs or if init/cont is FALSE, LabVIEW initializes the internal states to 0. If init/cont is TRUE, LabVIEW initializes the internal states to the final states from the previous call to this instance of this VI. To process a large data sequence that consists of smaller blocks, set this input to FALSE for the first block and to TRUE for continuous filtering of all remaining blocks.
	Filtered X is the output array of filtered samples.
	error returns any error or warning from the VI. You can wire error to the Error Cluster From Error Code VI to convert the error code or warning into an error cluster.

IIR Cascade Filter (CDB)

	X is the input array of samples to filter.
	IIR Filter Cluster contains the cascaded form of IIR filter coefficients. This cluster is the output from one of the IIR coefficient design VIs: Butterworth Coefficients, Bessel Coefficients, Chebyshev Coefficients, Elliptic Coefficients, or Inv Chebyshev Coefficients. filter structure selects IIR second-order or fourth-order filter stages. 0 IIR 2nd Order 1 IIR 4th Order Reverse Coefficients is the reverse coefficients of the IIR cascade filter. Forward Coefficients is the forward coefficients of the IIR cascade filter.
	init/cont controls the initialization of the internal states. The default is FALSE. The first time this VI runs or if init/cont is FALSE, LabVIEW initializes the internal states to 0. If init/cont is TRUE, LabVIEW initializes the internal states to the final states from the previous call to this instance of this VI. To process a large data sequence that consists of smaller blocks, set this input to FALSE for the first block and to TRUE for continuous filtering of all remaining blocks.
	Filtered X is the output array of filtered samples.
	error returns any error or warning from the VI. You can wire error to the Error Cluster From Error Code VI to convert the error code or warning into an error cluster.

IIR Cascade Filter Details

This IIR implementation is called cascade because it is a cascade of second- or fourth-order filter stages. The output of one filter stage is the input to the next filter stage for all N_s filter stages.

Example

Refer to the Online Filtering VI in the labview\examples\Signal Processing\Filters directory for an example of using the IIR Cascade Filter VI.

 Open example  Find related examples