# phasezd (MathScript RT Module Function)

LabVIEW 2012 MathScript RT Module Help

Edition Date: June 2012

Part Number: 373123C-01

»View Product Info Download Help (Windows Only)

Owning Class: filter design

Requires: MathScript RT Module

## Syntax

phasezd(b)

phasezd(b, a)

phasezd(b, a, w)

phasezd(b, a, w, fs)

phasezd(b, a, n)

phasezd(b, a, n, 'whole')

phasezd(b, a, n, fs)

phasezd(b, a, n, 'whole', fs)

h = phasezd(b, a, w)

h = phasezd(b, a, w, fs)

[h, f] = phasezd(b)

[h, f] = phasezd(b, a)

[h, f] = phasezd(b, a, n)

[h, f] = phasezd(b, a, n, 'whole')

[h, f] = phasezd(b, a, n, fs)

[h, f] = phasezd(b, a, n, 'whole', fs)

Legacy Name: `phasez`

## Description

Computes the phase response vector and the frequency vector of a filter. If you do not request an output, this function plots the unwrapped phase of the filter in the current plot window. phasezd(b) is equivalent to phasezd(b, , 512). phasezd(b, a) is equivalent to phasezd(b, a, 512).

Examples

## Inputs

Name Description
b Specifies the numerator coefficients of the filter. b is a vector.
a Specifies the denominator coefficients of the filter. a is a vector. The default is .
w Specifies the frequency points at which you want to evaluate the phase response. If you do not specify w, LabVIEW evaluates the phase response at n points equally spaced around the upper half of the unit circle. w is a vector.
fs Specifies the sampling frequency in Hz. fs is a scalar.
n Specifies the number of frequency points. n is a positive integer. The default is 512.
'whole' Directs LabVIEW to evaluate the phase response at n points equally spaced around the unit circle.

## Outputs

Name Description
h Returns the phase response vector of the filter. h is a real vector.
f Returns the discrete frequency vector in radians/sample that corresponds to h. f is a 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 = [1, 2];
a = [-1, 1, 1, 3];
n = 32;
[H, F] = phasezd(b, a, n)