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Create list of Nichols plot options


P = nicholsoptions
P = nicholsoptions('cstprefs')


P = nicholsoptions returns a list of available options for Nichols plots with default values set. You can use these options to customize the Nichols plot appearance from the command line.

P = nicholsoptions('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.

This table summarizes the Nichols plot options.

Title, XLabel, YLabelLabel text and style
TickLabelTick label style
Grid Show or hide the grid
Specified as one of: 'off' | 'on'
Default: 'off'
GridColorColor of the grid lines
Specified as one of: Vector of RGB values in the range [0,1]| color shorthand such as 'k' or 'r'|'none'.
Default: [0.15,0.15,0.15]
XlimMode, YlimMode Limit modes
Xlim, YlimAxes limits
IOGrouping Grouping of input-output pairs
Specified as one of: 'none' |'inputs'|'outputs'|'all'
Default: 'none'
InputLabels, OutputLabels Input and output label styles.
InputVisible, OutputVisibleVisibility of input and output channels

Frequency units, specified as one of:

  • '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'

MagLowerLimModeEnables a lower magnitude limit
Specified as one of: 'auto' | 'manual'
Default: 'auto'
MagLowerLimSpecifies the lower magnitude limit
PhaseUnits Phase units
Specified as one of: 'deg' | 'rad'
Default: 'deg'
PhaseWrapping Enables phase wrapping
Specified as one of: 'on' | 'off'
Default: 'off'
PhaseWrappingBranchPhase value at which the plot wraps accumulated phase when PhaseWrapping is set to 'on'.
Default: –180 (phase wraps into the interval [–180º,180º))
PhaseMatchingEnables phase matching
Specified as one of: 'on' | 'off'
Default: 'off'
PhaseMatchingFreqFrequency for matching phase
PhaseMatchingValueThe value to make the phase responses close to


collapse all

Create an options set, and set the phase units and grid option.

P = nicholsoptions; 
P.PhaseUnits = 'rad';
P.Grid = 'on';

Use the options set to generate a Nichols plot. Not the phase units and grid in the plot.

h = nicholsplot(tf(1,[1,.2,1,0]),P);

Figure contains an axes. The axes contains an object of type line. This object represents untitled1.

Introduced in R2008a