\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 = 
  <int32>  - size: [2 4]
 
Columns 1 to 4
 1  0  0  5  
 0  3  2  0  
--> nnz(a)
ans = 
  <int32>  - size: [1 1]
 4  
--> A = sparse(a)
A = 
  <int32>  - size: [2 4]
	Matrix is sparse with 4 nonzeros
--> nnz(A)
ans = 
  <int32>  - size: [1 1]
 4  

\end{verbatim}
