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based on an earlier version of the Wolfram Language.
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NicholsPlot

NicholsPlot[g]
gives the Nichols plot of a rational function g in one complex variable.
NicholsPlot[sys]
gives the Nichols plot of a TransferFunctionModel or StateSpaceModel object sys.
NicholsPlot
gives the plot for frequencies from to .
  • NicholsPlot gives the magnitude versus phase plot of the sinusoidal transfer function.
  • The unit of frequency is radians per time unit.
  • If the frequency range is not specified, an appropriate range is computed automatically.
AxesTruewhether to draw axes
ColorFunctionAutomatichow to apply coloring to the curve
ColorFunctionScalingTruewhether to scale arguments to ColorFunction
EvaluationMonitorNoneexpression to evaluate at every evaluation
ExclusionsAutomaticfrequencies to exclude
ExclusionsStyleNonewhat to draw at excluded frequencies
FeedbackType"Negative"the feedback type
MaxRecursionAutomaticthe maximum number of recursive subdivisions allowed
MeshAutomatichow many mesh divisions to draw
MeshFunctions{#3&}how to determine the placement of mesh divisions
MeshShadingNonehow to shade regions between mesh points
MeshStyleAutomaticthe style for mesh divisions
NicholsGridLinesNonethe Nichols grid lines to draw
PerformanceGoal$PerformanceGoalaspects of performance to try to optimize
PlotPointsAutomaticiniitial number of sample frequencies
PlotRangeAutomaticrange of magnitude and phase values to include
PlotRangeClippingTruewhether to clip at the PlotRange
PlotStyleAutomaticgraphics directives to specify the style of the plot
RegionFunctionAutomatichow to determine whether a point should be included
SamplingPeriodNonethe sampling period
ScalingFunctions{"Degree","dB"}the scaling functions
StabilityMarginsFalsewhether to show the stability margins
StabilityMarginsStyleAutomaticgraphics directives to specify the style of the stability margins
WorkingPrecisionMachinePrecisionthe precision used in internal computations
  • The phase scale phasescale can be or .
  • The magnitude scale magscale can be or , which correspond to the decibel and absolute values of the magnitude, respectively.
Nichols plot of a transfer function model:
Specify a system as an expression:
Specify the frequency range:
Nichols plot of a discrete-time system:
Nichols plot of a transfer function model:
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Specify a system as an expression:
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Specify the frequency range:
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Nichols plot of a discrete-time system:
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The Nichols plot of a continuous-time system:
The Nichols plot of a discrete-time system:
The system can also be specified as an expression:
A discrete-time system with sampling period 1, specified as an expression:
Specify the frequency range:
The Nichols plot of a state-space model:
Specify the aspect ratio:
Specify axes labels:
Color the curve by scaled frequency values:
Use a named color gradient:
Use red when the sensitivity function is less than 1, and black otherwise:
Scale the frequency to be between 0 and 1:
ColorFunctionScaling->False uses absolute values:
Specify the scaling manually:
Display the tooltip coordinates in radians and absolute magnitude:
By default the singular frequencies are excluded:
Show equally spaced frequency locations:
Show the coordinates at 1 radian per time unit:
Show the coordinates at several frequencies:
Specify the graphics directives:
By default the mesh is located at evenly spaced frequencies:
Specify a mesh with evenly spaced log-10 frequency values:
Specify the mesh style:
Use automatically chosen values of closed-loop magnitude and phase:
Draw specific contours:
Use more initial points to get a smoother curve:
A continuous-time system:
A discrete-time system:
The discrete-time system specified as an object:
Show the phase in radians:
Show absolute values of magnitude:
Show stability margins:
Show only the gain margin:
Only margins and crossover frequencies with numerical values are shown:
Specify stability margins style:
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