Function Reference

pole

Compute the poles of an LTI system

Syntax

• p = pole(sys)
  

Description

pole computes the poles p of the SISO or MIMO LTI model sys.

Algorithm

For state-space models, the poles are the eigenvalues of the matrix, or the generalized eigenvalues of in the descriptor case.

For SISO transfer functions or zero-pole-gain models, the poles are simply the denominator roots (see roots).

For MIMO transfer functions (or zero-pole-gain models), the poles are computed as the union of the poles for each SISO entry. If some columns or rows have a common denominator, the roots of this denominator are counted only once.

Limitations

Multiple poles are numerically sensitive and cannot be computed to high accuracy. A pole with multiplicity typically gives rise to a cluster of computed poles distributed on a circle with center and radius of order

where is the relative machine precision (eps).

See Also
damp        Damping and natural frequency of system poles

esort, dsort  Sort system poles

pzmap       Pole-zero map

zero        Compute (transmission) zeros

place

pzmap