Definition:Filtering Function/2 Dimensional

Definition
Let $\operatorname {sinc}: \R \to \R$ denote the filtering function.

The $2$-dimensional form of $\operatorname {sinc}$ is defined and denoted:
 * $\forall x, y \in \R: \map {\operatorname { {}^2 sinc} } {x, y} := \map {\operatorname {sinc} } x \map {\operatorname {sinc} } y$