User`s guide

8 Model Analysis
Next Steps After Getting an Accurate Model
After you get an accurate model, you can simulate or predict model output.
For more info rmation, see Chapter 9, “Simulation and Prediction”.
Forlinearparametricmodels(
idmodel objects), you can perform the following
operations:
• Transform between continuous-time and discrete-time representation.
See “Transforming Between Discrete-Time and Continuous-Time
Representations” on page 3-112.
• Transform betwee n linear model representations, such as between
polynomial, state-space, and zero-pole representations.
See “Transforming B etw een Linear M odel Representations” on page 3-117.
• Extract numerical data from transfer functions, pole-zero models, and
state-space matrices.
See “Extracting Parameter Values from Linear Models” on page 3-108.
For nonlinear black-bo x mode ls (
idnlarx and idnlhwobjects), you can perform
the following operations:
• Compute a linear approximation of the nonlinear model.
See “Computing Linear Approximations of Nonlinear Black-Box Models”
on page 4-33.
• Extract model parameters.
See “Extracting Parameter V alues from Nonlinear Black-Box Models” on
page 4-30.
System Identification Toolbox models in the MATLAB workspace are
immediately available to other MathWorks™ products. However, if you used
the System Identification Tool GUI to estimate models, you must first export
the models to the MATLA B workspace.
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