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Plot root locus and return plot handle


h = rlocusplot(sys)
rlocusplot(..., plotoptions)


h = rlocusplot(sys) computes and plots the root locus of the single-input, single-output LTI model sys. It also returns the plot handle h. You can use this handle to customize the plot with the getoptions and setoptions commands. Type

help pzoptions 

for a list of available plot options.

See rlocus for a discussion of the feedback structure and algorithms used to calculate the root locus.

rlocusplot(sys,k) uses a user-specified vector k of gain values.

rlocusplot(sys1,sys2,...) draws the root loci of multiple LTI models sys1, sys2,... on a single plot. You can specify a color, line style, and marker for each model, as in


rlocusplot(AX,...) plots into the axes with handle AX.

rlocusplot(..., plotoptions) plots the root locus with the options specified in plotoptions. Type

help pzoptions 

for more details.


Use the plot handle to change the title of the plot.

sys = rss(3);
h = rlocusplot(sys);
p = getoptions(h); % Get options for plot.
p.Title.String = 'My Title'; % Change title in options.
setoptions(h,p); % Apply options to plot.


You can change the properties of your plot, for example the units. For information on the ways to change properties of your plots, see Ways to Customize Plots.

Version History

Introduced before R2006a