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Discrete-time, direct-form, FIR filter


Hd = dfilt.dffir(b)
Hd = dfilt.dffir


Hd = dfilt.dffir(b) returns a discrete-time, direct-form finite impulse response (FIR) filter, Hd, with numerator coefficients, b.

Hd = dfilt.dffir returns a default, discrete-time, direct-form FIR filter, Hd, with b=1. This filter passes the input through to the output unchanged.

The resulting filter states column vector is



Create a direct-form FIR discrete-time filter with coefficients from a 30th order lowpass equiripple design:

b = firpm(30,[0 .1 .2 .5]*2,[1 1 0 0]);
Hd = dfilt.dffir(b)

Introduced before R2006a

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