Function Reference: rlocus

Function File: rlocus (sys)

Function File: [rldata, k] = rlocus (sys, increment, min_k, max_k)

Display root locus plot of the specified SISO system.

Inputs

sys: LTI model. Must be a single-input and single-output (SISO) system.
increment: The increment used in computing gain values.
min_k: Minimum value of k.
max_k: Maximum value of k.

Outputs

rldata: Data points plotted: in column 1 real values, in column 2 the imaginary values.
k: Gains for real axis break points.

Block Diagram

 u    +         +---+      +------+             y
------>(+)----->|k |----->|SISO |-------+------->
        ^ -     +---+      +------+       |
        |                                |
        +---------------------------------+

Demonstration 1

The following code

 s = tf('s');
 g = (s^2+2*s+2)/(s*(s^4+9*s^3+33*s^2+51*s+26));
 rlocus(g);

Produces the following figure

Figure 1

Package: control