# impzd (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

## Syntax

impzd(b)

impzd(b, a)

impzd(b, a, n)

impzd(b, a, n, f)

impzd(b, a, [], f)

[r, t] = impzd(b)

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

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

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

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

Legacy Name: `impz`

## 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.

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 .
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

The following table lists the support characteristics of this function.

 Supported in the LabVIEW Run-Time Engine Yes (if you request output) Supported on RT targets Yes (if you request output) Suitable for bounded execution times on RT Not characterized

## Examples

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