iopzmap

Plot pole-zero map for I/O pairs of model

Syntax

iopzmap(sys) iopzmap(sys1,sys2,...)

Description

iopzmap(sys)computes and plots the poles and zeros of each input/output pair of the dynamic system modelsys. The poles are plotted as x's and the zeros are plotted as o's.

iopzmap(sys1,sys2,...)shows the poles and zeros of multiple modelssys1,sys2,... on a single plot. You can specify distinctive colors for each model, as iniopzmap(sys1,'r',sys2,'y',sys3,'g').

The functionssgridorzgridcan be used to plot lines of constant damping ratio and natural frequency in thesorzplane.

For model arrays,iopzmapplots the poles and zeros of each model in the array on the same diagram.

Examples

collapse all

Pole-Zero Map for MIMO System

This example uses:

Control System Toolbox Control System Toolbox

Open Live Script

Create a one-input, two-output dynamic system.

H = [tf(-5 ,[1 -1]); tf([1 -5 6],[1 1 0])];

Plot a pole-zero map.

iopzmap(H)

Figure contains 2 axes objects. Axes object 1 contains 2 objects of type line. This object represents H. Axes object 2 contains 2 objects of type line. This object represents H.

iopzmapgenerates a separate map for each I/O pair in the system.

Pole-Zero Map of Identified Model

This example uses:

Open Live Script

View the poles and zeros of an over-parameterized state-space model estimated from input-output data. (Requires System Identification Toolbox™).

loadiddata1sys = ssest(z1,6,ssestOptions('focus','simulation')); iopzmap(sys)

Figure contains an axes object. The axes object with title From: u1 To: y1 contains 2 objects of type line. This object represents sys.

The plot shows that there are two pole-zero pairs that almost overlap, which hints are their potential redundancy.

Tips

For additional options for customizing the appearance of the pole-zero plot, useiopzplot.

Version History

Introduced in R2012a