tt> where the first   matrix derivative was nonempty. Alternatively, <tt>mconlagrhess()</tt> can   be defined instead.
               </li>
               <li>the 2nd derivative of the lagrangian of the <tt>k</tt>-th nonlinear matrix   constraint (<tt>k=1..NANLN</tt>); Matrix Constraint Lagrangian is defined as
               </li>
            </ul>
         </div><pre>    |MCL_k(x,Y,Umlt) = &lt;A_k(x,Y),Umlt&gt; = trace(A_k(x,Y) * Umlt)|</pre><p>where <tt>Umlt</tt> is provided Lagrangian multiplier for the