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In addition to the following options, the NyquistPlot command takes many of the standard plot options; see plot,options.

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frequencies = list or Vector of nonnegative values

Specifies frequencies to be used to generate a frequency response. The list or Vector must be sorted, from smallest to largest. The units are determined by the hertz option.
Specifies the unit of frequency. If this value is set to true, the unit of frequency is Hertz; otherwise, it is radians per second. The default value is assigned by DynamicSystems[SystemOptions].
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legend = list or element

Specifies the legend for the plot. A list specifies a legend entry for each subsystem. The elements in the list correspond to the Matrix of subsystems taken in Fortran order. An element can be used for a onebyone Matrix of subsystems. The default is no legend.
Specifies the frequency scale. If this value is set to , the scale is linear; otherwise, by default, the scale is logarithmic.
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method = function or matrix

Selects the method used to compute the frequency response. The function method generates the transfer functions of sys and evaluates them at the selected frequencies. The matrix method generates the statespace matrices of sys and evaluates the expression at specific values of . The default is to use the function method for frequencydomain systems (TF, Coeff, and ZPK), and to use the matrix method for timedomain systems (DE and SS).
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numpoints = nonnegative integer

Specifies the number of points. The default is 100.
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output = plot, data, or list of same

Specifies the output of NyquistPlot. The name plot returns the plot structure. The name data returns the data. A list of those names returns a corresponding list of plots and data. The default is plot.
The data is returned as a Matrix for a single selected subsystem and as a list of Matrices for multiple selected subsystems. Each Matrix has two columns: the first is the horizontal component and the second is the vertical component.
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parameters = set(name = complexcons) or list(name = complexcons)

Specifies numeric values for parameters in sys. These values override those specified by the parameters field of the system object, which in turn override the settings in in . The numeric value on the righthand side of each equation is substituted for the name on the lefthand side in the expressions that define the model. No checking is done during the substitution to determine whether the substituted value is valid. For example, a complex value can be substituted for the coefficient of a polynomial. If the complex value had been originally assigned to the model at creation, a warning would be generated.
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range = range( realcons )

Specifies the frequency range to plot. The default setting is to compute an appropriate range based on the locations of the zeros and poles of the transfer functions of the selected subsystems. Similarly, if the rhs of range is infinity, a maximum is computed based on the zeros and poles. The units are specified by the hertz option.
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subsystem = [ posint, posint ] or list of same

Selects subsystems of a multiinput/multioutput system. Each selected subsystem is specified as a list of two indices: the first specifies the output and the second specifies the input. For example, specifies the subsystem from the second input to the first output. A list of lists selects multiple subsystems. The default setting is to select all subsystems, using Fortran ordering. That is, for an m x n system, the default list of subsystems is [ [1,1], ..., [m,1], ..., [1,n], ..., [m,n] ].