Learn more about System Identification Toolbox

Viewing Model Parameters

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Viewing Model Parameter Values Viewing Parameter Uncertainties

Viewing Model Parameter Values

You can view the numerical parameter values and other information about the model P2DUe2 by right-clicking the model icon in the System Identification Tool GUI. The Data/model Info dialog box opens.

The noneditable area of the dialog box lists the model coefficients that correspond to the following model structure:

For the model P2DUe2:

• Kp is 0.99783.

• Tw is 0.99874.

• Zeta is 0.10829.

• Td is 2.0058.

These coefficients agree with the model used to simulate the data:

P2DUe2 also includes an additive noise term, where H is a second-order ARMA model and e is white noise:

The Data/model Info dialog box gives the noise model H as a ratio of two polynomials, C(s)/D(s), where:

C(s) = s^2 + 2.14(+-0.08596)s + 1.175(+-0.3083)
D(s) = s^2 + 0.2427(+-0.08213)s + 0.61(+-0.07577)

The 1-standard-deviation uncertainty for the model parameters is in parentheses next to each parameter value.

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Viewing Parameter Uncertainties

To view parameter uncertainties for the system transfer function, click Present in the Data/model Info dialog box, and view the information in the MATLAB Command Window.

Kp = 0.99738+-0.01951
Tw = 0.99874+-0.0037075
Zeta = 0.10829+-0.0040998
Td = 2.0058+-0.002329

The 1-standard-deviation uncertainty for each model parameter follows the +- symbol.

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Estimating a Transfer Function with a Noise Model

Exporting the Model to the MATLAB Workspace

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