(i) | $E \subseteq X$ is a D78: Subset of $X$ |

**diameter**of $E$ in $M$ is the D1699: Basic number \begin{equation} \sup_{x, y \in E} d(x, y) \end{equation}

Definition D1224

Set diameter

Formulation 0

Let $M = (X, d)$ be a D1107: Metric space such that

The **diameter** of $E$ in $M$ is the D1699: Basic number
\begin{equation}
\sup_{x, y \in E} d(x, y)
\end{equation}

(i) | $E \subseteq X$ is a D78: Subset of $X$ |