2.6. Download source via SVN


As of Oct 2016, SVN support is now implemented via a git-to-subversion interface service on GitHub and no longer through a mirror of the internal SVN repository at Sandia.

You must have the Subversion (SVN) client software installed on your system to communicate with the Git server in this mode.

You can follow LAMMPS development on 3 different SVN branches:

  • stable : this branch is updated with every stable release
  • unstable : this branch is updated with every patch release
  • master : this branch continuously follows ongoing development

The corresponding command lines to do an initial checkout are as follows. (Note that unlike Git, you must perform a separate checkout into a unique directory for each of the 3 branches.)

svn checkout https://github.com/lammps/lammps.git/branches/unstable mylammps
svn checkout https://github.com/lammps/lammps.git/branches/stable mylammps
svn checkout https://github.com/lammps/lammps.git/trunk mylammps

where “mylammps” is the name of the directory you wish to create on your machine.

Once the command completes, your directory will contain the same files as if you unpacked a current LAMMPS tarball, with two exceptions:

1) No LAMMPS packages are initially installed in the src dir (a few packages are installed by default in the tarball src dir). You can install whichever packages you wish before building LAMMPS; type “make package” from the src dir to see the options, and the Packages doc page for a discussion of packages.

2) The HTML documentation files are not included. They can be fetched from the LAMMPS website by typing “make fetch” in the doc directory. Or they can be generated from the content provided in doc/src by typing “make html” from the the doc directory.

After initial checkout, as bug fixes and new features are added to LAMMPS, as listed on this page, you can stay up-to-date by typing the following SVN commands from within the “mylammps” directory:

svn update

You can also check if there are any updates by typing:

svn -qu status

Doing an “update” will not change any files you have added to the LAMMPS directory structure. It will also not change any existing LAMMPS files you have edited, unless those files have changed in the repository. In that case, SVN will attempt to merge the new repository file with your version of the file and tell you if there are any conflicts. See the SVN documentation for details.

Please refer to the subversion client support help pages on GitHub if you want to use advanced features like accessing particular previous release versions via tags.

Once you have updated your local files with an “svn update” (or “svn co”), you still need to re-build LAMMPS if any source files have changed. To do this, you should cd to the src directory and type:

make purge             # remove any deprecated src files
make package-update    # sync package files with src files
make foo               # re-build for your machine (mpi, serial, etc)

just as described on the Install patch doc page, after a patch has been installed.


If you wish to edit/change a src file that is from a package, you should edit the version of the file inside the package sub-directory with src, then re-install the package. The version in the src dir is merely a copy and will be wiped out if you type “make package-update”.

The LAMMPS GitHub project is managed by Christoph Junghans (LANL, junghans at lanl.gov), Axel Kohlmeyer (Temple U, akohlmey at gmail.com) and Richard Berger (Temple U, richard.berger at temple.edu).