def set_distributed_assembled_values(self, a_loc):
        """Set the distributed assembled matrix values.

        Distributed assembled matrices require setting icntl(18) != 0.
        """
        assert a_loc.size == self._refs['irn_loc'].size
        self._refs.update(a_loc=a_loc)
        self.id.a_loc = self.cast_array(a_loc)