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impz

Impulse response of digital filter

Syntax

[h,t] = impz(b,a)
[h,t] = impz(sos)
[h,t] = impz(d)
[h,t] = impz(...,n)
[h,t] = impz(...,n,fs)
impz(...)

Description

[h，t] = impz（b，a）returns the impulse response of the filter with numerator coefficients, b, and denominator coefficients, a. impz chooses the number of samples and returns the response in the column vector, h, and the sample times in the column vector, t. t = [0:n-1]' and n = length(t) is computed automatically.

[h,t] = impz(sos)returns the impulse response for the second-order sections matrix, sos. sos is a K-by-6 matrix, where the number of sections, K, must be greater than or equal to 2. If the number of sections is less than 2, impz considers the input to be a numerator vector. Each row of sos corresponds to the coefficients of a second order (biquad) filter. The ith row of the sos matrix corresponds to [bi(1) bi(2) bi(3) ai(1) ai(2) ai(3)].

[h,t] = impz(d) returns the impulse response of a digital filter, d. Use designfilt to generate d based on frequency-response specifications.

[h,t] = impz(...,n) computes n samples of the impulse response when n is an integer (t = [0:n-1]'). If n is a vector of integers, impz computes the impulse response at those integer locations, starting the response computation from 0 (and t = n or t = [0 n]). If, instead of n, you include the empty vector, [], for the second argument, the number of samples is computed automatically.

[h,t] = impz(...,n,fs) computes n samples and produces a vector t of length n so that the samples are spaced 1/fs units apart.

impz(...) with no output arguments plots the impulse response of the filter.

impz works for both real and complex input systems.

文章来源: reborn.blog.csdn.net，作者：李锐博恩，版权归原作者所有，如需转载，请联系作者。

原文链接：reborn.blog.csdn.net/article/details/83342602