User`s guide

Transforming Between Linear Model Representations
Transforming Between Linear Model Representations
You can transfo rm linear models between state-space and polynomial form s.
You can also transform between frequency-response, state-space, and
polynomial forms.
If you used the System Identication Tool GUI to es timate models, you must
export the models to the MATLAB workspace before converting models.
For detailed information about each command in the following table, see the
corresponding reference page.
Commands for Transforming Model Representations
Command Model Type to Convert Usage Example
idfrd
Converts any single- or
multiple-output
idmodel
object to idfrd model.
If you have the Control
System Toolbox product, this
command converts a ny L TI
object.
To get frequency response of
m at default
frequen cies, use the following command:
m_f = idfrd(m)
To get frequency response at specic
frequen cies, use the following command:
m_f = idfrd(m,f)
To get frequency response for a submodel
from input
2 to output 3,usethe
following command:
m_f = idfrd(m(2,3))
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