Response Computation and Visualization

Analyze model response on time- and frequency-response plots

You can plot and visualize the response of a dynamic system model using System Identification Toolbox™ functions. Additionally, you can customize plots using plot options and properties.

Functions

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Compute Responses

Identified Models

`sim`	Simulate response of identified model
`simOptions`	Option set for `sim`
`findstates`	Estimate initial states of model
`findstatesOptions`	Option set for `findstates`
`spectrum`	Plot or return output power spectrum of time series model or disturbance spectrum of linear input/output model
`data2state`	Map past data to states of state-space and nonlinear ARX models

Dynamic System Models

`bode`	Bode frequency response of dynamic system
`nyquist`	Nyquist response of dynamic system
`step`	Step response of dynamic system
`stepinfo`	Rise time, settling time, and other step-response characteristics
`impulse`	Impulse response plot of dynamic system; impulse response data
`lsim`	Compute time response simulation data of dynamic system to arbitrary inputs
`lsiminfo`	Compute linear response characteristics
`pzmap`	Pole-zero map of dynamic system
`iopzmap`	Plot pole-zero map for input-output pairs of dynamic system using default options

Plot Responses

Identified Models

spectrumplot Plot disturbance spectrum of linear identified models

Dynamic System Models

`bodeplot`	Plot Bode frequency response of dynamic system
`bodemag`	Magnitude-only Bode plot of frequency response
`nyquistplot`	Plot Nyquist response of dynamic system
`stepplot`	Plot step response of dynamic system
`impulseplot`	Plot impulse response of dynamic system
`lsimplot`	Plot simulated time response of dynamic system to arbitrary inputs
`pzplot`	Plot pole-zero map of dynamic system
`iopzplot`	Plot pole-zero map for input-output pairs of dynamic system
`addResponse`	Add dynamic system response to existing response plot (Since R2024b)
`showConfidence`	Display confidence regions on response plots for identified models
`zoomcp`	Zoom Nyquist plot to region around critical point

Visualization Options

`spectrumoptions`	Option set for `spectrumplot`
`RespConfig`	Options for step or impulse responses (Since R2023a)
`bodeoptions`	Plot options for `bodeplot`
`nyquistoptions`	Create list of Nyquist plot options
`timeoptions`	Create list of time plot options
`pzoptions`	Options for pole-zero plots
`getoptions`	Get options for `idplot` and `spectrumplot`
`setoptions`	Set options for `idplot` and `spectrumplot`

Toolbox Settings

identpref Configure System Identification Toolbox settings

Properties

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Plot Configuration

ImpulsePlot Properties	Access impulse plot properties (Since R2024b)
LSimPlot Properties	Access simulated time response plot properties (Since R2024b)
StepPlot Properties	Access step plot properties (Since R2024b)
BodePlot Properties	Access Bode plot properties (Since R2024b)
NyquistPlot Properties	Access Nyquist plot properties (Since R2024b)
HSVPlot Properties	Access Hankel singular value plot properties (Since R2024b)
IOPZPlot Properties	Access input-output pole-zero plot properties (Since R2024b)
PZPlot Properties	Access pole-zero plot properties (Since R2024b)

Topics

Analyzing MIMO Models
In analysis plots of multiple-input, multiple output LTI models, there are plot tools for selecting subsystems and grouping I/O pairs.
Customize Linear Analysis Plots Using Property Editor
Interactively set axes labels and limits, fonts, grids, and other attributes of response plots.
Specify Toolbox Settings for Linear Analysis Plots
Set linear analysis plot settings that persist between MATLAB^® sessions.