Control System Toolbox™

dsort - Sort discrete-time poles by magnitude

Syntax

dsort
[s,ndx] = dsort(p)

Description

dsort sorts the discrete-time poles contained in the vector p in descending order by magnitude. Unstable poles appear first.

When called with one lefthand argument, dsort returns the sorted poles in s.

[s,ndx] = dsort(p) also returns the vector ndx containing the indices used in the sort.

Example

Sort the following discrete poles.

p =
  -0.2410 + 0.5573i
  -0.2410 - 0.5573i
   0.1503         
  -0.0972         
  -0.2590 

s = dsort(p)

s =
  -0.2410 + 0.5573i
  -0.2410 - 0.5573i
  -0.2590         
   0.1503         
  -0.0972 

Limitations

The poles in the vector p must appear in complex conjugate pairs.

See Also

eig, esort, sort, pole, pzmap, zero

drss

dss