# zplane

Zero-pole plot for discrete-time systems

## Syntax

## Description

`zplane(`

plots the zeros and poles of discrete-time systems in the current figure window.
Specify the zeros in a column vector `z`

,`p`

)`z`

and the poles in a
column vector `p`

. The symbol `'o'`

represents a zero and the symbol `'x'`

represents a pole. The
plot includes the unit circle for reference.

If `z`

and `p`

are matrices, then
`zplane`

plots the poles and zeros in the columns of
`z`

and `p`

in different
colors.

`zplane(`

finds and plots the
zeros and poles of the digital filter represented as Cascaded Transfer Functions (CTF) with numerator coefficients `B,A`

,"ctf")`B`

and denominator
coefficients `A`

.* (since R2024b)*

## Examples

## Input Arguments

## Output Arguments

## More About

## Tips

You can override the automatic scaling of

`zplane`

usingaxis([xmin xmax ymin ymax])

after calling

`zplane`

. This scaling is useful when one or more zeros or poles have such a large magnitude that the others are grouped tightly around the origin and are hard to distinguish.

## References

[1] Lyons, Richard G.
*Understanding Digital Signal Processing*. Upper Saddle River,
NJ: Prentice Hall, 2004.

## Version History

**Introduced before R2006a**