freqsd (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

freqsd(b, a)

freqsd(b, a, n)

freqsd(b, a, w1)

h = freqsd(b, a)

h = freqsd(b, a, n)

h = freqsd(b, a, w1)

[h, w2] = freqsd(b, a)

[h, w2] = freqsd(b, a, n)

[h, w2] = freqsd(b, a, w1)

Legacy Name: `freqs`

Description

Computes the s-domain Laplace transform frequency response. If you do not request an output, this function plots the magnitude and phase of the filter in the current plot window.

Examples

Inputs

Name Description
b Specifies the numerator coefficients of the filter. b is a real or complex vector.
a Specifies the denominator coefficients of the filter. a is a real or complex vector.
n Specifies the number of frequency points. n is a positive integer. The default is 200.
w1 Specifies the frequency values. w1 is a vector.

Outputs

Name Description
h Returns the complex frequency response.
w2 Returns the frequency values. w2 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

[H, W] = freqsd([1 2 3], [2 1 3]);
loglog(W, abs(H))