Domain of Variable/Examples/Countries in Europe

Example of Domain of Variable
Let $C$ be a country in Europe.

The domain of $C$ is the set $\set {\text {France}, \text {Germany}, \text {Spain}, \text {Italy}, \ldots}$

These can be represented numerically if desired, by assigning an integer to each of the countries in Europe, for example:
 * $1: \text {France}$
 * $2: \text {Germany}$
 * $3: \text {Spain}$
 * $4: \text {Italy}$
 * $\vdots$

$C$ is a discrete variable.