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Member of the filter design class.

Syntax

freqs(b, a)

freqs(b, a, n)

freqs(b, a, w1)

h = freqs(b, a)

h = freqs(b, a, n)

h = freqs(b, a, w1)

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

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

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

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.

Details

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

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

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

Related Topics

freqspace
freqz
invfreqs