spZeros
==============================================

Purpose
----------------
Creates a sparse matrix containing no non-zero values.

Format
----------------
.. function:: y = spZeros(r, c)

    :param r: rows of output matrix.
    :type r: scalar

    :param c: columns of output matrix.
    :type c: scalar

    :return y: sparse matrix containing no non-zero values. 

    :rtype y: RxC sparse matrix

Examples
----------------

::

    sparse matrix y;

    // Create a 4x3 sparse matrix with all elements set to 0
    y = spZeros(4, 3);

    // Create a dense matrix with the same values as 'y'
    d = spToDense(y);

The contents of *d* are equal to:

::

    0 0 0
    0 0 0
    0 0 0
    0 0 0

Remarks
-------

Since sparse matrices are strongly typed in GAUSS, *y* must be defined as
a sparse matrix before the call to :func:`spZeros`.

.. seealso:: Functions :func:`spOnes`, :func:`spEye`