Signal Processing Toolbox

Zero-Pole Analysis

The zplane function plots poles and zeros of a linear system. For example, a simple filter with a zero at -1/2 and a complex pole pair at and is

zer = -0.5; 
pol = 0.9*exp(j*2*pi*[-0.3 0.3]');

The zero-pole plot for the filter is

zplane(zer,pol)

For a system in zero-pole form, supply column vector arguments z and p to zplane.

zplane(z,p)

For a system in transfer function form, supply row vectors b and a as arguments to zplane.

zplane(b,a)

In this case zplane finds the roots of b and a using the roots function and plots the resulting zeros and poles.

See Linear System Models for details on zero-pole and transfer function representation of systems.

Delay

Linear System Models