Set Partition/Examples/Integers by Sign

Examples of Set Partitions
Let $\Z$ denote the set of integers.

Let $\Z_{> 0}$ denote the set of strictly positive integers.

Let $\Z_{< 0}$ denote the set of strictly negative integers.

Let $\Z_0$ denote the singleton $\set 0$

Then $P = \set {\Z_{> 0}, \Z_{< 0}, \Z_0}$ forms a partition of $\Z$.