User`s guide

5 ODE P ara meter Estimation (Grey-Box Modeling)
• y — Represents the right side(s) of the o utput equation(s). A column vector
with Ny entries.
The fi le inputs are:
•
t — Current time.
•
x — State vector at time t. For sta t ic models, equals [].
•
u —Inputvectorattimet. For time-se rie s models, equals [].
•
p1,p2, ...,p N — Parameters, which can be real scalars, column vectors
or two-dimensional matrices.
N is the number of parameter objects. For
scalar parameters,
N is the total number of parameter elements.
•
FileArgument — Contains a uxiliary variables that might be required for
updating the constants in the state equations.
Tip After creating a model file, call it directly from the MATLAB software
with reasonable inputs and verify the output values.
For an example of creating grey-box model files a nd idnlgr ey model object,
see the demo Creating idnlgrey Model F iles.
Constructing the idnlgrey Object
After you create the M-file or MEX-file with your model structure, you must
define an
idnlgrey object. This object s hares many of the properties of the
linear
idgrey model object.
Use the following syntax to define the
idnlgrey model object:
m = idnlgrey('filename',Order,Parameters,InitialStates)
The id nlgr ey arguments are defined as follows:
•
'filename' —NameoftheM-fi le or MEX-file storing the mode l structure.
This file must be on the MATLAB path when you use this model object for
model estimation , pred icti on , or simulation .
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