Simulation and prediction— At the command line, usesimandpredictto simulate and predict the model output. To compare models to measured output and to each other, usecompare. For information about plotting simulated and predicted output in the app, seeSimulation and Prediction in the App. You can also specify the initial conditions for simulation and prediction. The toolbox provides several options to facilitate how you specify initial states. For example, you can usefindstatesanddata2stateto compute state values based on the requirement to maximize fit to measured output or based on operating conditions. See theidnlarxreference page for a definition of the nonlinear ARX model states. To learn more about howsimandpredictcompute the model output, seeHow the Software Computes Nonlinear ARX Model Output.

You can also forecast the response of a dynamic system by using theforecastcommand. The command predicts future outputs of the system using past output measurements. For more information, seeForecasting Response of Nonlinear ARX Models.

Linearization— Compute linear approximation of nonlinear ARX models using线性化orlinapp.

The线性化command provides a first-order Taylor series approximation of the system about an operating point.linappcomputes a linear approximation of a nonlinear model for a given input data. For more information, see theLinear Approximation of Nonlinear Black-Box Models. You can compute the operating point for linearization usingfindop.

After computing a linear approximation of a nonlinear model, you can perform linear analysis and control design on your model using Control System Toolbox™ commands. For more information, seeUsing Identified Models for Control Design ApplicationsandCreate and Plot Identified Models Using Control System Toolbox Software.

Simulation and code generation using Simulink^®— You can import estimated nonlinear ARX models into the Simulink software using the Nonlinear ARX block (IDNLARX Model) from the System Identification Toolbox block library. Import theidnlarxobject from the workspace into Simulink using this block to simulate the model output.

TheIDNLARX Modelblock supports code generation withSimulink Coder™software, using both generic and embedded targets. Code generation does not work when the model containsidCustomNetworkoridFeedforwardNetworknonlinearity estimator, or custom regressors. For more information, seeSimulate Identified Model in Simulink.