\section{I-J Square Root of Negative One}

\subsection{Usage}

Returns a \verb|complex| value that represents the square root of -1.  There are two
functions that return the same value:
\begin{verbatim}
   y = i
\end{verbatim}
and 
\begin{verbatim}
   y = j.
\end{verbatim}
This allows either \verb|i| or \verb|j| to be used as loop indices.  The returned value is a 32-bit complex value.
\subsection{Example}

The following examples demonstrate a few calculations with \verb|i|.
\begin{verbatim}
--> i

ans = 

    0.0000 +  1.0000i 

--> i^2

ans = 

   -1.0000 +  0.0000i 


\end{verbatim}
The same calculations with \verb|j|:
\begin{verbatim}
--> j

ans = 

    0.0000 +  1.0000i 

--> j^2

ans = 

   -1.0000 +  0.0000i 


\end{verbatim}
Here is an example of how \verb|i| can be used as a loop index and then recovered as the square root of -1.
\begin{verbatim}
--> accum = 0; for i=1:100; accum = accum + i; end; accum

ans = 

 5050 

--> i

ans = 

 100 

--> clear i
--> i

ans = 

    0.0000 +  1.0000i 


\end{verbatim}
