IIR Filter (Not in Base Package)

Filters the input sequence X using the direct form IIR filter specified by Reverse Coefficients and Forward Coefficients. Details

init/cont controls the initialization of the internal states. When init/cont is FALSE (default), the internal states are initialized to zero. When init/cont is TRUE, the internal filter states are initialized to the final filter states from the previous call to this instance of this VI. To filter a large data sequence that has been split into smaller blocks, set this control to FALSE for the first block and to TRUE for continuous filtering of all remaining blocks.
X is the input array of samples to be filtered.
Reverse Coefficients is the reverse coefficients of the filter design. This VI does not place any restrictions on the coefficient arrays. If both coefficient arrays are empty, the VI performs no filtering and sets Filtered X to the value of X.

Note  You can use the IIR Filter VI to perform FIR filtering by passing an empty array into Reverse Coefficients.
Forward Coefficients is the forward coefficients of the filter design.
Filtered X is the output array of filtered samples.
error returns any error or warning from the VI. Refer to Signal Processing Error Codes for more information about these conditions.

IIR Filter Details

If Y represents the output sequence Filtered X, the IIR Filter VI obtains the elements of Y using

,

where n is the number of Forward Coefficients, represented by , and m is the number of Reverse Coefficients, represented by

.

Note  You can use the IIR Filter VI to implement the FIR filtering operation by leaving Reverse Coefficients unwired and by wiring the FIR filter coefficients to Forward Coefficients.