# Quick questions regarding RoCs with Z transforms

1. Dec 1, 2014

### pjcircle

Hi I was wondering when there is only one pole for a function's z-transform then the RoC can only be either left or right sided not two sided and then two sided requires having two or more poles so you actually have an "inner" region to be between then? Or does the entire z-plane just not including the ring of that one pole count as 2sided?

Last edited: Dec 1, 2014
2. Dec 7, 2014