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Filters the input sequence X using the direct-form FIR filter specified by FIR Coefficients. The data type you wire to the X input determines the polymorphic instance to use.

Details  

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

Select an instance FIR Filter (DBL)FIR Filter (CDB)

FIR Filter (DBL)

	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.
	X is the input array of samples to filter.
	FIR Coefficients is the coefficients of the FIR filter. If FIR Coefficients is unwired, the VI sets Filtered X to the value of X and does not perform filtering.
	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.

FIR Filter (CDB)

	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.
	X is the input array of samples to filter.
	FIR Coefficients is the coefficients of the FIR filter. If FIR Coefficients is unwired, the VI sets Filtered X to the value of X and does not perform filtering.
	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.

FIR Filter Details

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

where y is Filtered X, N_b is the number of FIR Coefficients, and b_j is FIR Coefficients.