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getpvec

Obtain model parameters and associated uncertainty data

Syntax

pvec = getpvec(sys)
[pvec,pvec_sd] = getpvec(sys)
[___] = getpvec(sys,'free')

Description

pvec = getpvec(sys) returns a vector, pvec, containing the values of all the parameters of the identified model sys.

[pvec,pvec_sd] = getpvec(sys) also returns the 1 standard deviation value of the uncertainty associated with the parameters of sys. If the model covariance information for sys is not available, pvec_sd is [].

[___] = getpvec(sys,'free') returns data for only the free parameters of sys, using any of the output arguments in previous syntaxes. For idnlarx and idnlhw models, all parameters are treated as free.

Input Arguments

sys

Identified model.

Identified model, specified as an idtf, idss, idgrey, idpoly, idproc, idnlarx, idnlhw, or idnlgrey model or an array of such models.

Output Arguments

pvec

Values of the parameters of sys.

If sys is an array of models, then pvec is a cell array with parameter value vectors corresponding to each model in sys. pvec is [] for idnlarx and idnlhw models that have not been estimated.

pvec_sd

1 standard deviation value of the parameters of sys.

If the model covariance information for sys is not available, pvec_sd is []. Thus, pvec_sd is always [] for idnlarx and idnlhw models because these models do not store parameter covariance information.

If sys is an array of models, then pvec_sd is a cell array with standard deviation vectors corresponding to each model in sys.

Examples

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Load the estimation data.

load iddata1 z1;

Estimate a transfer function model.

sys = tfest(z1,3);

Retrieve the parameter values from the estimated model.

pvec = getpvec(sys);

Load the estimation data

load iddata2 z2;

Estimate a state-space model.

sys = ssest(z2,3);

Retrieve the model parameters, pvec, and associated standard deviations, pvec_sd, from the estimated model.

[pvec,pvec_sd] = getpvec(sys);

Load the estimation data.

load iddata2 z2;

Estimate a state-space model.

sys = ssest(z2,3);

Retrieve the values of the free parameters from the estimated model.

pvec = getpvec(sys,'free');

Version History

Introduced in R2012a