Definition:Distance to Nearest Integer Function

From ProofWiki
Jump to navigation Jump to search

Definition

The distance to nearest integer function $\norm \cdot: \R \to \closedint 0 {\dfrac 1 2}$ is defined in the following ways:


Definition 1

$\norm \alpha:= \min \set {\size {n - \alpha}: n \in \Z}$


Definition 2

$\norm \alpha:= \min \set {\set \alpha, 1 - \set \alpha}$

where $\set \alpha$ is the fractional part of $\alpha$.


Also denoted as

The notation $\norm \cdot_{\R / \Z}$ is also in use.


Also see