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3.9 Graphics Functions 353
3.9.5 RootLocusPlot
RootLocusPlot[func, {k, k , k }]
displays the root locus of func as k is swept from k to k
RootLocusPlot[func]
RootLocusPlot[rootloc]
Command structure of RootLocusPlot.
displays a pole/zero diagram of func
displays a root locus calculated with RootLocusByQZ
RootLocusPlot displays a root locus plot of a transfer function Hs k, where k denotes a realvalued
parameter. A root locus plot shows the trajectories of the poles and zeros of Hs k in the
complex plane as k varies from k to k . RootLocusPlot can also be used to produce a pole/zero
diagram of transfer function Hs without parameters as well as to display root loci calculated with
RootLocusByQZ.
By default, RootLocusPlot chooses a logarithmic representation of the complex plane for better
visualization of widely separated poles and zeros. However, as logarithmic scaling is inappropriate
for coordinates near the axes, the regions around the axes are scaled semi-logarithmically, and the
region around the origin is scaled linearly. RootLocusPlot marks the linearly scaled region with a
gray background. The semi-logarithmic regions are the regions above and below as well as to the
left and the right of the linear region.
You can customize the appearance of root locus plots with the following options. In addition,
RootLocusPlot inherits many options from Graphics. Both the options which are specific to
RootLocusPlot as well as the inherited options can be set with SetOptions[RootLocusPlot, opts].