User`s guide

Creating Model Structures at the Command Line
Categories of Model Properties
The way a model object stores information is defined by the properties of the
corresponding model class.
Each model object has properties for storing information that are relevant
only to that specific model type. However, the
idarx, idgrey , idpoly, idpro c,
and
idss model objects are based on the idmodel superclass and inherit all
idmodel properties.
Similarly, the nonlinear m odels
idnlarx, idnlhw,andidnl grey are based on
the
idnlmodel superclass and inherit all idnlmodel properties.
In general, all nonlinear model objects have properties that belong to the
following categories:
• Names o f input and output channels, such as
InputName and OutputName
• Sampling interval of the model, such as Ts
• Units for time or frequency
• Model order and mathematical structure (for ex ample, O DE or
nonlinearities)
• Properties that store estimation results and model uncertainty
• User co mments, such as
Notes and U serd ata
• Estimation algorithm information
- Algorithm
Structure includes fields that specify the estimation method. Algor ithm
includes another structure, called Advanced, which provides additional
flexibility for setting the search algorithm. Different fields apply to
different estimation techniques.
Forlinearparametricmodels,
Algorithm specifies the frequency
weighing of the estimation using the
Focus property.
Note Algorithm does not apply to idfrd models.
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