idnlarx/operspec

Construct operating point specification object for idnlarx model

Syntax

spec = operspec(nlsys)

Description

spec = operspec(nlsys) creates a default operating point specification object for the idnlarx model nlsys. This object is used with findop and specifies constraints on the model input and output signal values. Modify the default specifications using dot notation.

Input Arguments

nlsys — Nonlinear ARX model

idnlarx object

Nonlinear ARX model, specified as an idnlarx object.

Output Arguments

spec — Operating point specification

operating point specification object

Operating point specification, used to determine an operating point of the idnlarx model using findop, returned as an object containing the following:

• Input — Structure with fields:

  Field	Description	Default for Each Input
  Value	Initial guesses or fixed levels for the values of the model inputs, specified as a vector with length equal to the number of input signals.	0
  Min	Minimum value constraints on the model inputs, specified as a vector with length equal to the number of input signals.	-Inf
  Max	Maximum value constraints on the model inputs, specified as a vector with length equal to the number of input signals.	Inf
  Known	Known value indicator, specified as a logical vector with length equal to the number of input signals and with the following values: true — findop will set the corresponding input signal to Value. false — findop will estimate the corresponding input signal using Value as an initial guess.	true

• Output — Structure with fields:

  Field	Description	Default for Each Output
  Value	Initial guesses for the values of the model outputs, specified as a vector with length equal to the number of output signals.	0
  Min	Minimum value constraints on the model outputs, specified as a vector with length equal to the number of output signals.	-Inf
  Max	Maximum value constraints on the model outputs, specified as a vector with length equal to the number of output signals.	Inf