message: added error message for auxiliary element number out of range
diff: @@ -661,7 +661,11 @@ void TACSAssembler::setAuxElements( TACSAuxElements *_aux_elems ){
  naux = auxElements->getAuxElements(&aux);
  for ( int k = 0; k < naux; k++ ){
  int elem = aux[k].num;
  - if (elements[elem]->numVariables() !=
  + if (elem < 0 || elem >= numElements){
  + fprintf(stderr, "[%d] Element number %d out of range [0,%d)\n",
  + mpiRank, elem, numElements);
  + }
  + else if (elements[elem]->numVariables() !=
  aux[k].elem->numVariables()){
  fprintf(stderr, "[%d] Auxiliary element sizes do not match\n",
  mpiRank);
  