-breaking function <tt>obj</tt>.
 
 A special case of tie-breaking is the "first-set" rule where we are
 only interested in evaluating a function in the first polyhedron which
 contains <tt>x</tt> (despite the fact there can be multiple such sets). This
 is achieved by
 
 <tt>fval = U.feval(x, 'function_name', 'tiebreak', @(x) 0)</tt>
 
 Notes:
 <ul>
     
         <li> Tie-breaking functions must be scalar-valued.</li>
     
         <li> No tie-breaking is done by default. </li>
 
      </ul>
 
 
      <b