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Function Reference: rlocusx

Function File: rlocusx (sys)
Function File: rlocusx (sys, increment, min_k, max_k)

Interactive root locus plot of the specified SISO system SYS.

This functions directly calls rlocus() from the control package which must be installed and loaded. In contrast to rlocus(), mouse clicks on the root locus display the related gain and all other poles resulting from this gain together with damping and frequency of conjugate complex pole pairs.
All possible interaction by mouse clicks or keys are:

Left click: Gain, damping and Frequency

Displays related gain and all resulting closed loop poles together with damping and frequency

s: Step response

Simulates the step response for the gain of of the most recently selected pole locations

i: Impulse response

Simulates the impulse response for the most recently selected gain

b: Bode plot

Provides the open loop bode plot for the most recently selected gain

m: Stability margins

Provides the open loop bode plot with stability margins for the most recently selected gain

a: All plots

Provide sall four aforementioned plots

c: Clear

Removes all closed loop pole markers and annotations

d: Delete

Removes all open figures with simulation and bode plots

x: Exit

Exits the interactive mode and re-activates the octave prompt

There are no output parameters.



LTI model. Must be a single-input and single-output (SISO) system.


The increment used in computing gain values.


Minimum value of k.


Maximum value of k.


Plots the interactive root locus to the screen.
Unlike rlocus(), this function does not have any output parameters. For output parameters please directly use rlocus().

See also: rlocus

Source Code: rlocusx