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fir_fs (MathScript RT Module Function)

LabVIEW 2012 MathScript RT Module Help

Edition Date: June 2012

Part Number: 373123C-01

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Owning Class: filter design

Requires: MathScript RT Module


b = fir_fs(n, f, a)

b = fir_fs(n, f, a, w)

Legacy Name: fir2


Uses frequency sampling to design a linear phase FIR filter. fir_fs windows the impulse response with a Hamming window.



Name Description
n Specifies the filter order. n is a nonnegative integer. n must be even for filters with a non-zero gain at the Nyquist frequency. If n does not meet this condition, LabVIEW increases n by 1.
f Specifies the frequencies at which you want to take samples. 1 represents the Nyquist frequency. f is a real vector of ascending values in the interval [0, 1]. length(f) must equal length(a).
a Specifies the magnitudes at each of the f frequencies. a is a real vector. length(a) must equal length(f).
w Specifies the symmetric window to apply to the impulse response. w is a real vector of length n + 1.


Name Description
b Returns the filter coefficients of order n. b is a real vector.


The following table lists the support characteristics of this function.

Supported in the LabVIEW Run-Time Engine Yes
Supported on RT targets Yes
Suitable for bounded execution times on RT Not characterized


N = 13;
F = [0, 0.1, 0.5, 0.7, 1];
A = [0, 1, 1, 0, 0];
B = fir_fs(N, F, A)

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