# 3.4 Mapping

A mapping $\mu$ relates elements of its domain $d$ to elements of its range $r$ as follows.

 $\mu(d)=r$

A mapping resides in a data structure that supports two operations:

• Map links an element $r$ in the range of $\mu$ to an arbitrary element $d$ in the domain of $\mu$, i.e. sets $\mu(d)$ to $r$.

• Evaluate evaluates the mapping $\mu$ for an arbitrary element $d$ in its domain, i.e. returns $\mu(d)$.