static int convergences;
  static int progress_errors;
  static int limit_errors;
  static int unknown_errors;
  
  NLFunc fcn(&Hybrd_Solver::f_hybrd);
  NLEqn	 eqn(Solver::_ui,fcn);
  //  eqn.set_tolerance(0.01);
  Solver::_ui = eqn.solve(info);

  switch (info)
    {
    case 1:
      convergences++;
      break;