rlocusplot (Control System Toolbox)

Calculate the root locus and return the plot handle

Syntax

h = rlocusplot(sys)

h = rlocusplot(sys,k)
h = rlocusplot(sys1,sys2,...)
h = rlcousplot(AX,...)
h = rlocusplot(..., plotoptions)

Description

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(sys1,'r',sys2,'y:',sys3,'gx')

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.

Example

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

sys = rss(3,2,2);
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.

See Also
getoptions Get plot options

rlocus Calculate root loci of LTI models

setoptions Set plot options

rlocus rss