User`s guide

8 Model Analysis
true system response. You can specify the confidence interval as a probability
(between 0 and 1) or as the number of standard deviations of a Gaussian
distribution. For example, a probability of 0.99 (99%) corresponds to 2.58
standard deviations.
Note The calculation of the confidence interval assum es that the model
sufficiently describes the system dynamics and the m odel residuals pass
independence tests.
How to Plot Impulse and Step Response at the
Command Line
You can plot impulse- and step-response plots using the impulse and step
commands, respectively.
All plot commands have the same basic syntax, as follows:
• To plot one model, use the syntax
command(model).
• To plot several models, use the syntax
command(model1,model2,...,modelN).
In this case,
command represents any of the plotting commands.
To display confidence inter va ls for a sp ecified number of standard deviations,
use the following syntax:
command(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.
To display a filled confidence region, use the following syntax:
command(model, 'sd' ,sd,'fill')
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