\begin{Schunk}
\begin{Sinput}
  dat$grp
\end{Sinput}
\begin{Soutput}
 [1] 1 2 1 3 1 1 2 2 2 1 2 2 2 3 3 3 3 1 3
\end{Soutput}
\end{Schunk}
