\begin{Schunk}
\begin{Sinput}
 x4a <- c("a" = 1, "b" = 3, "c" = 9.1)
 ## Retrieve by index or name
 x4a[2]
\end{Sinput}
\begin{Soutput}
b 
3 
\end{Soutput}
\begin{Sinput}
 x4a["b"]
\end{Sinput}
\begin{Soutput}
b 
3 
\end{Soutput}
\end{Schunk}
