\section{WHICH Get Information on Function}

\subsection{Usage}

Returns information on a function (if defined).  The usage is
\begin{verbatim}
   which(fname)
\end{verbatim}
where \verb|fname| is a \verb|string| argument that contains the name of the 
function.  For functions and scripts defined
via \verb|.m| files, the \verb|which| command returns the location of the source
file:
\begin{verbatim}
   y = which(fname)
\end{verbatim}
will return the filename for the \verb|.m| file corresponding to the given
function, and an empty string otherwise.
\subsection{Example}

First, we apply the \verb|which| command to a built in function.
\begin{verbatim}
--> which fft
Function fft is a built in function

\end{verbatim}
Next, we apply it to a function defined via a \verb|.m| file.
\begin{verbatim}
--> which fliplr
Function fliplr, M-File function in file '/home/basu/dev/trunk/FreeMat2/src/toolbox/array/fliplr.m'

\end{verbatim}
