ode></td>
<td>Swaps the contents of the sub vectors.</td>
</tr>

<tr>
<td><code>const_iterator begin () const</code></td>
<td>Returns a <code>const_iterator</code> pointing to the beginning
of the <code>matrix_column</code>.</td>
</tr>

<tr>
<td><code>const_iterator end () const</code></td>
<td>Returns a <code>const_iterator</code> pointing to the end of
the <code>matrix_column</code>.</td>
</tr>

<tr>
<td><code>iterator begin ()</code> </td>
<td>Returns a <code>iterator</code> pointing to the beginning of
