Let \(M\) be a metric space . The diameter of a subset \(S\subseteq M\) is defined by
\begin{equation*} \diam S = \sup \{d(x,y)\mid x,y\in S\}. \end{equation*}Let \(M\) be a metric space . The diameter of a subset \(S\subseteq M\) is defined by
\begin{equation*} \diam S = \sup \{d(x,y)\mid x,y\in S\}. \end{equation*}