User`s guide

8 Model Analysis
Zeros and Poles Plot Settings (Continued)
Action
Command
Show the unit circle. Select Style > Unit circle. Select this option
again to hide the unit circle.
(Multiple-output system
only)
Select an input-output
pair to view the poles
and zeros corresponding
to those channels.
SelecttheoutputbynameintheChannel menu.
How to P lot Poles and Zeros at the Comma nd Line
You can create a pole-zero plot for linear polynomial, linear state-space, and
linear grey-box models using the
pzmap command. pzmap lets you include
several models on a plot.
To display confidence inter va ls for a sp ecified number of standard deviations,
use the following syntax:
pzmap(model,'sd',sd)
where sd is the number of standard deviations of a Gaussian distributio n. For
example, a confidence value of 99% for the nominal model curve corresponds
to 2.58 stand a rd d e v ia t ions.
Command
Description
Exampl e
pzmap
Plots zeros and poles
of the model on the
S-plane or Z-plane for
continuous-time or
discrete-time model,
respectively.
To plot the p oles and
zeros of the model
mod,usethefollowing
command:
pzmap(mod)
For detailed information about pzmap, see the corresponding reference page.
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