\section{ISFLOAT Test for Floating Point Array}

\subsection{Usage}

The syntax for \verb|isfloat| is
\begin{verbatim}
   x = isfloat(y)
\end{verbatim}
and it returns a logical 1 if the argument is a floating 
point array (i.e., a \verb|float| or \verb|double|), and a logical
0 otherwise.
