\section{NNZ Number of Nonzeros}

\subsection{Usage}

Returns the number of nonzero elements in a matrix.
The general format for its use is
\begin{verbatim}
   y = nnz(x)
\end{verbatim}
This function returns the number of nonzero elements
in a matrix or array.  This function works for both
sparse and non-sparse arrays.  For 
\subsection{Example}

\begin{verbatim}
--> a = [1,0,0,5;0,3,2,0]

a = 

 1 0 0 5 
 0 3 2 0 

--> nnz(a)

ans = 

 4 

--> A = sparse(a)

A = 
	Matrix is sparse with 4 nonzeros
--> nnz(A)

ans = 

 4 


\end{verbatim}
