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Filters x using the direct form IIR filter specified by Reverse Coefficients and Forward Coefficients.

This VI is similar to the IIR Filter VI.

Details  

	initialize, when TRUE, initializes the internal state of the VI.
	x is the input signal to filter.
	Reverse Coefficients is the reverse coefficients of the filter design. If the set of reverse coefficients is empty, the forward coefficients should be empty too. Otherwise, the VI returns an error. If both sets of coefficient inputs are empty, Filtered x is set equal to x.
	Forward Coefficients is the forward coefficients of the filter design.
	Filtered x contains the result of filtering the input sequence x by convolution.
	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 Filter PtByPt Details

The IIR Filter PtByPt VI obtains the elements of Filtered X using the following equation.

,

where Y is Filtered X, N_b is the number of Forward Coefficients, b_j is Forward Coefficients, N_a is the number of Reverse Coefficients, and a_k is Reverse Coefficients.

Note  You can use the IIR Filter PtByPt VI to perform FIR filtering by passing an empty array into Reverse Coefficients.