Definition:Partial Subtraction

Definition
Partial subtraction is the operation $\dot - : \N \times \N \to \N$ defined on the set of natural numbers $\N$ as follows:


 * $\forall a, b \in \N: a \mathop{\dot -} b = \begin{cases}

0 & : a < b \\ a - b & : a \ge b \end{cases}$ where $a - b$ denotes proper subtraction.

Also known as

 * Cut-off subtraction