/* -*- c++ -*- ---------------------------------------------------------- LAMMPS - Large-scale Atomic/Molecular Massively Parallel Simulator https://www.lammps.org/, Sandia National Laboratories Steve Plimpton, sjplimp@sandia.gov Copyright (2003) Sandia Corporation. Under the terms of Contract DE-AC04-94AL85000 with Sandia Corporation, the U.S. Government retains certain rights in this software. This software is distributed under the GNU General Public License. See the README file in the top-level LAMMPS directory. ------------------------------------------------------------------------- */ #ifdef FIX_CLASS // clang-format off FixStyle(addforce,FixAddForce); // clang-format on #else #ifndef LMP_FIX_ADDFORCE_H #define LMP_FIX_ADDFORCE_H #include "fix.h" namespace LAMMPS_NS { class FixAddForce : public Fix { public: FixAddForce(class LAMMPS *, int, char **); ~FixAddForce() override; int setmask() override; void init() override; void setup(int) override; void min_setup(int) override; void post_force(int) override; void post_force_respa(int, int, int) override; void min_post_force(int) override; double compute_scalar() override; double compute_vector(int) override; double memory_usage() override; private: double xvalue, yvalue, zvalue; int varflag, iregion; char *xstr, *ystr, *zstr, *estr; char *idregion; int xvar, yvar, zvar, evar, xstyle, ystyle, zstyle, estyle; double foriginal[4], foriginal_all[4]; int force_flag; int ilevel_respa; int maxatom; double **sforce; }; } // namespace LAMMPS_NS #endif #endif /* ERROR/WARNING messages: E: Illegal ... command Self-explanatory. Check the input script syntax and compare to the documentation for the command. You can use -echo screen as a command-line option when running LAMMPS to see the offending line. E: Region ID for fix addforce does not exist Self-explanatory. E: Variable name for fix addforce does not exist Self-explanatory. E: Variable for fix addforce is invalid style Self-explanatory. E: Cannot use variable energy with constant force in fix addforce This is because for constant force, LAMMPS can compute the change in energy directly. E: Must use variable energy with fix addforce Must define an energy variable when applying a dynamic force during minimization. */