5.15. Removed commands and packages

This page lists LAMMPS commands and packages that have been removed from the distribution and provides suggestions for alternatives or replacements. LAMMPS has special dummy styles implemented, that will stop LAMMPS and print a suitable error message in most cases, when a style/command is used that has been removed or will replace the command with the direct alternative (if available) and print a warning.

5.15.1. Fix ave/spatial and fix ave/spatial/sphere

Deprecated since version 11Dec2015.

The fixes ave/spatial and ave/spatial/sphere have been removed from LAMMPS since they were superseded by the more general and extensible “chunk infrastructure”. Here the system is partitioned in one of many possible ways through the compute chunk/atom command and then averaging is done using fix ave/chunk. Please refer to the chunk HOWTO section for an overview.

5.15.2. Box command

Deprecated since version 22Dec2022.

The box command has been removed and the LAMMPS code changed so it won’t be needed. If present, LAMMPS will ignore the command and print a warning.

5.15.3. Reset_ids, reset_atom_ids, reset_mol_ids commands

Deprecated since version 22Dec2022.

The reset_ids, reset_atom_ids, and reset_mol_ids commands have been folded into the reset_atoms command. If present, LAMMPS will replace the commands accordingly and print a warning.

5.15.4. LATTE package

Deprecated since version 15Jun2023.

The LATTE package with the fix latte command was removed from LAMMPS. This functionality has been superseded by fix mdi/qm and fix mdi/qmmm from the MDI package. These fixes are compatible with several quantum software packages, including LATTE. See the examples/QUANTUM dir and the MDI coupling HOWTO page. MDI supports running LAMMPS with LATTE as a plugin library (similar to the way fix latte worked), as well as on a different set of MPI processors.

5.15.5. MEAM package

The MEAM package in Fortran has been replaced by a C++ implementation. The code in the MEAM package is a translation of the Fortran code of MEAM into C++, which removes several restrictions (e.g. there can be multiple instances in hybrid pair styles) and allows for some optimizations leading to better performance. The pair style meam has the exact same syntax. For a transition period the C++ version of MEAM was called USER-MEAMC so it could coexist with the Fortran version.

5.15.6. Minimize style fire/old

Deprecated since version 8Feb2023.

Minimize style fire/old has been removed. Its functionality can be reproduced with fire with specific options. Please see the min_modify command documentation for details.

5.15.7. Pair style mesont/tpm, compute style mesont, atom style mesont

Deprecated since version 8Feb2023.

Pair style mesont/tpm, compute style mesont, and atom style mesont have been removed from the MESONT package. The same functionality is available through pair style mesocnt, bond style mesocnt and angle style mesocnt.

5.15.8. REAX package

The REAX package has been removed since it was superseded by the REAXFF package. The REAXFF package has been tested to yield equivalent results to the REAX package, offers better performance, supports OpenMP multi-threading via OPENMP, and GPU and threading parallelization through KOKKOS. The new pair styles are not syntax compatible with the removed reax pair style, so input files will have to be adapted. The REAXFF package was originally called USER-REAXC.

5.15.9. USER-CUDA package

The USER-CUDA package had been removed, since it had been unmaintained for a long time and had known bugs and problems. Significant parts of the design were transferred to the KOKKOS package, which has similar performance characteristics on NVIDIA GPUs. Both, the KOKKOS and the GPU package are maintained and allow running LAMMPS with GPU acceleration.

5.15.10. restart2data tool

The functionality of the restart2data tool has been folded into the LAMMPS executable directly instead of having a separate tool. A combination of the commands read_restart and write_data can be used to the same effect. For added convenience this conversion can also be triggered by command line flags