System Identification | ![]() ![]() |
This section contains detailed descriptions of all of the functions of user interest in the System Identification Toolbox. It begins with a list of functions grouped by subject area and continues with the entries in alphabetical order .
Information is also available through the on-line Help facility. By typing a function name without arguments, you also get immediate syntax help about its arguments for most functions
For ease of use, most functions have several default arguments. The Syntax first lists the function with the necessary input arguments and then with all the possible input arguments. The functions can be used with any number of arguments between these extremes. The rule is that missing, trailing arguments are given default values, as defined in the manual. Default values are also obtained by entering the arguments as the empty matrix [ ].
MATLAB does not require that you specify all of the output arguments; those not specified are not returned. For functions with several output arguments in the System Identification Toolbox, missing arguments are, as a rule, not computed, in order to save time.
Functions listed by Category
Help Functions |
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help ident |
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idhelp |
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idprops, |
The Graphical User Interface |
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Simulation and Prediction |
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Data Manipulation |
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Nonparametric Estimation |
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Estimate impulse response and covariance functions using correlation analysis. |
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Estimate impulse and step responses using high order parametric models. |
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Estimate spectra and transfer functions using direct Fourier techniques. |
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Estimate spectra and transfer functions using spectral analysis. |
Parameter Estimation |
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Estimate ARX model using four-stage instrumental variable method. |
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Model Structure Creation |
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Create a greybox linear model using an M-file that you write. |
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Create a model structure for input-output models defined as numerator and denominator polynomials. |
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Create model structure for linear state-space models with known and unknown parameters. |
Manipulating Model Structures |
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Model Conversions |
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Convert |
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Conversion of |
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Model Analysis |
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Plot model characteristics using the LTI Viewer in the Control System Toolbox. |
Model Validation |
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Compare model's simulated or predicted output with actual output |
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Assessing Model Uncertainty |
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Compute loss functions for sets of output error model structures.
Model Structure Selection
arxstruc
ivstruc
n4sid
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selstruc
struc
Recursive Parameter Estimation |
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Estimate general input-output models using a recursive prediction error method. |
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Estimate general input-output models using a recursive pseudo-linear regression method. |
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General |
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![]() | Reference | Functions Listed Alphabetically | ![]() |