\begin{Schunk}
\begin{Sinput}
 dat$wn <- paste0(dat$w, dat$rn)
 head(dat[ ,c("w", "rn", "wn")])
\end{Sinput}
\begin{Soutput}
  w rn wn
1 g  1 g1
2 f  2 f2
3 i  3 i3
4 h  4 h4
5 g  5 g5
6 i  6 i6
\end{Soutput}
\end{Schunk}
