rv_ptr            156 src/grid_GridAndTime_impl.cpp   const auto rv_ptr = max_element(cbegin(v), cend(v));
rv_ptr            157 src/grid_GridAndTime_impl.cpp   if(rv_ptr == cend(v)) throw logic_error {"Error in max()"};
rv_ptr            158 src/grid_GridAndTime_impl.cpp   return *rv_ptr;