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Member of the filter design class.

Syntax

impz(b)

impz(b, a)

impz(b, a, n)

impz(b, a, n, f)

impz(b, a, [], f)

[r, t] = impz(b)

[r, t] = impz(b, a)

[r, t] = impz(b, a, n)

[r, t] = impz(b, a, n, f)

[r, t] = impz(b ,a, [], f)

Description

Computes the impulse response of a filter. If you do not request an output, this function plots the impulse response in the current plot window.

Details

Examples

Inputs

Name	Description
b	Specifies the forward filter coefficients. b is a real vector.
a	Specifies the backward filter coefficients. a is a real vector. The default is [1].
n	Specifies the number of equidistant points for which to compute an impulse response. If you specify [] for n, LabVIEW determines the number of points automatically. If you do not specify n, LabVIEW determines the number of points according to a. n is a nonnegative integer or a vector of such numbers.
f	Specifies the distance d between equidistant points, where d = 1/f. f is a positive real number.

Outputs

Name	Description
r	Returns the impulse response of the filter defined by a and b. r is a real vector.
t	Returns the time values of the impulse response. t is a real vector.

Details

This function is supported in the LabVIEW Run-Time Engine only if you request an output from the function. This function can remain in your scripts when you build a stand-alone application or shared library, but if you do not request an output, the LabVIEW Run-Time Engine does not execute this function. If you request an output, the LabVIEW Run-Time Engine executes this function as normal.

Examples

b = [1];
a = [1, 0.2, -0.02, 1];
n = 10;
f = 2;
[R, T] = impz(b, a, n, f)

Related Topics

filter
filter2
freqz
stepz