nyquistoptions

List of Nyquist plot options

Syntax

P = nyquistoptions
P = nyquistoptions('cstprefs')

Description

P = nyquistoptions returns the default options for Nyquist plots. You can use these options to customize the Nyquist plot appearance using the command line.

P = nyquistoptions('cstprefs') initializes the plot options with the options you selected in the Control System Toolbox Preferences Editor. For more information about the editor, see Toolbox Preferences Editor in the User's Guide documentation.

The following table summarizes the Nyquist plot options.

Option Description
Title, XLabel, YLabel Label text and style
TickLabelTick label style
Grid Show or hide the grid
Specified as one of the following strings: 'off' | 'on'
Default: 'off'
XlimMode, YlimModeLimit modes
Xlim, Ylim Axes limits
IOGrouping Grouping of input-output pairs
Specified as one of the following strings: 'none' |'inputs'|'output'|'all'
Default: 'none'
InputLabels, OutputLabels Input and output label styles
InputVisible, OutputVisibleVisibility of input and output channels
FreqUnits

Frequency units, specified as one of the following strings:

  • 'Hz'

  • 'rad/second'

  • 'rpm'

  • 'kHz'

  • 'MHz'

  • 'GHz'

  • 'rad/nanosecond'

  • 'rad/microsecond'

  • 'rad/millisecond'

  • 'rad/minute'

  • 'rad/hour'

  • 'rad/day'

  • 'rad/week'

  • 'rad/month'

  • 'rad/year'

  • 'cycles/nanosecond'

  • 'cycles/microsecond'

  • 'cycles/millisecond'

  • 'cycles/hour'

  • 'cycles/day'

  • 'cycles/week'

  • 'cycles/month'

  • 'cycles/year'

Default: 'rad/s'

You can also specify 'auto' which uses frequency units rad/TimeUnit relative to system time units specified in the TimeUnit property. For multiple systems with different time units, the units of the first system are used.

MagUnits Magnitude units
Specified as one of the following strings: 'dB' | 'abs'
Default: 'dB'
PhaseUnits Phase units
Specified as one of the following strings: 'deg' | 'rad'
Default: 'deg'
ShowFullContourShow response for negative frequencies
Specified as one of the following strings: 'on' | 'off'
Default: 'on'
ConfidenceRegionNumberSDNumber of standard deviations to use to plotting the response confidence region (identified models only).
Default: 1.
ConfidenceRegionDisplaySpacingThe frequency spacing of confidence ellipses. For identified models only.
Default: 5, which means the confidence ellipses are shown at every 5th frequency sample.

Examples

This example shows how to create a Nyquist plot displaying the full contour (the response for both positive and negative frequencies).

P = nyquistoptions;
P.ShowFullContour = 'on'; 
h = nyquistplot(tf(1,[1,.2,1]),P);
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