nparams

Number of model parameters

Syntax

np = nparams(sys) np = nparams(sys,'free')

np = nparams(sys) returns the number of parameters in the identified model sys.

np = nparams(sys,'free') returns the number free estimation parameters in the identified model sys.

Note

Not all model coefficients are parameters, such as the leading entry of the denominator polynomials in idpoly and idtf models.

sys

Identified linear model.

`np`	Number of parameters of `sys`. For the syntax `np = nparams(sys,'free')`, `np` is the number of free estimation parameters of `sys`. `idgrey` models can contain non-scalar parameters. `nparams` accounts for each individual entry of the non-scalar parameters in the total parameter count.

Obtain the number of parameters of a transfer function model.

sys = idtf(1,[1 2]);
np = nparams(sys);

Obtain the number of free estimation parameters of a transfer function model.

sys0 = idtf([1 0],[1 2 0]);
sys0.Structure.Denominator.Free(3) = false;
np = nparams(sys,'free');