3.6. Include packages in build
In LAMMPS, a package is a group of files that enable a specific set of features. For example, force fields for molecular systems or rigid-body constraints are in packages. In the src directory, each package is a sub-directory with the package name in capital letters.
An overview of packages is given on the Packages doc page. Brief overviews of each package are on the Packages details doc page.
When building LAMMPS, you can choose to include or exclude each package. In general there is no need to include a package if you never plan to use its features.
If you get a run-time error that a LAMMPS command or style is “unknown”, it is often because the command is contained in a package, and your build did not include that package. If the command or style is available in a package included in the LAMMPS distribution, the error message will indicate which package would be needed. Running LAMMPS with the -h command-line switch will print all optional commands and packages that were enabled when building that executable.
For the majority of packages, if you follow the single step below to include it, you can then build LAMMPS exactly the same as you would without any packages installed. A few packages may require additional steps, as explained on the Build extras doc page.
These links take you to the extra instructions for those select packages:
The mechanism for including packages is simple but different for CMake versus make.
CMake build:
-D PKG_NAME=value # yes or no (default)
Examples:
-D PKG_MANYBODY=yes
-D PKG_USER-INTEL=yes
All standard and user packages are included the same way. Note that USER packages have a hyphen between USER and the rest of the package name, not an underscore.
See the shortcut section below for how to install many packages at once with CMake.
Note
If you toggle back and forth between building with CMake vs make, no packages in the src directory can be installed when you invoke cmake. CMake will give an error if that is not the case, indicating how you can un-install all packages in the src dir.
Traditional make:
cd lammps/src
make ps # check which packages are currently installed
make yes-name # install a package with name
make no-name # un-install a package with name
make mpi # build LAMMPS with whatever packages are now installed
Examples:
make no-rigid
make yes-user-intel
All standard and user packages are included the same way.
See the shortcut section below for how to install many packages at once with make.
Note
You must always re-build LAMMPS (via make) after installing or un-installing a package, for the action to take effect.
Note
You cannot install or un-install packages and build LAMMPS in a single make command with multiple targets, e.g. make yes-colloid mpi. This is because the make procedure creates a list of source files that will be out-of-date for the build if the package configuration changes within the same command. You can include or exclude multiple packages in a single make command, e.g. make yes-colloid no-manybody.
CMake and make info:
Any package can be included or excluded in a LAMMPS build, independent of all other packages. However, some packages include files derived from files in other packages. LAMMPS checks for this and does the right thing. Individual files are only included if their dependencies are already included. Likewise, if a package is excluded, other files dependent on that package are also excluded.
When you download a LAMMPS tarball or download LAMMPS source files from the git repository, no packages are pre-installed in the src directory.
Note
Prior to Aug 2018, if you downloaded a tarball, 3 packages (KSPACE, MANYBODY, MOLECULE) were pre-installed in the src directory. That is no longer the case, so that CMake will build as-is without the need to un-install those packages.
CMake shortcuts for installing many packages:
Instead of specifying all the CMake options via the command-line, CMake allows initializing its settings cache using script files. These are regular CMake files which can manipulate and set CMake variables (which represent selected options), and can also contain control flow constructs for more complex operations.
LAMMPS includes several of these files to define configuration “presets”, similar to the options that exist for the Make based system. Using these files you can enable/disable portions of the available packages in LAMMPS. If you need a custom preset you can take one of them as a starting point and customize it to your needs.
cmake -C ../cmake/presets/all_on.cmake [OPTIONS] ../cmake # enable all packages
cmake -C ../cmake/presets/all_off.cmake [OPTIONS] ../cmake # disable all packages
cmake -C ../cmake/presets/minimal.cmake [OPTIONS] ../cmake # enable just a few core packages
cmake -C ../cmake/presets/most.cmake [OPTIONS] ../cmake # enable most common packages
cmake -C ../cmake/presets/nolib.cmake [OPTIONS] ../cmake # disable packages that do require extra libraries or tools
cmake -C ../cmake/presets/clang.cmake [OPTIONS] ../cmake # change settings to use the Clang compilers by default
cmake -C ../cmake/presets/mingw.cmake [OPTIONS] ../cmake # enable all packages compatible with MinGW compilers
Note
Running cmake this way manipulates the CMake settings cache in your current build directory. You can combine multiple presets and options in a single cmake run, or change settings incrementally by running cmake with new flags.
Example:
# build LAMMPS with most commonly used packages, but then remove
# those requiring additional library or tools, but still enable
# GPU package and configure it for using CUDA. You can run.
mkdir build
cd build
cmake -C ../cmake/presets/most.cmake -C ../cmake/presets/nolib.cmake -D PKG_GPU=on -D GPU_API=cuda ../cmake
# to add another package, say BODY to the previous configuration you can run:
cmake -D PKG_BODY=on .
# to reset the package selection from above to the default of no packages
# but leaving all other settings untouched. You can run:
cmake -C ../cmake/presets/no_all.cmake .
Make shortcuts for installing many packages:
The following commands are useful for managing package source files and their installation when building LAMMPS via traditional make. Just type “make” in lammps/src to see a one-line summary.
These commands install/un-install sets of packages:
make yes-all # install all packages
make no-all # uninstall all packages
make yes-standard or make yes-std # install standard packages
make no-standard or make no-std # uninstall standard packages
make yes-user # install user packages
make no-user # uninstall user packages
make yes-lib # install packages that require extra libraries
make no-lib # uninstall packages that require extra libraries
make yes-ext # install packages that require external libraries
make no-ext # uninstall packages that require external libraries
which install/un-install various sets of packages. Typing “make package” will list all the these commands.
Note
Installing or un-installing a package for the make based build process works by simply copying files back and forth between the main source directory src and the sub-directories with the package name (e.g. src/KSPACE, src/USER-ATC), so that the files are included or excluded when LAMMPS is built. Only source files in the src folder will be compiled.
The following make commands help manage files that exist in both the src directory and in package sub-directories. You do not normally need to use these commands unless you are editing LAMMPS files or are installing a patch downloaded from the LAMMPS web site.
Type “make package-status” or “make ps” to show which packages are currently installed. For those that are installed, it will list any files that are different in the src directory and package sub-directory.
Type “make package-installed” or “make pi” to show which packages are currently installed, without listing the status of packages that are not installed.
Type “make package-update” or “make pu” to overwrite src files with files from the package sub-directories if the package is installed. It should be used after a patch has been applied, since patches only update the files in the package sub-directory, but not the src files.
Type “make package-overwrite” to overwrite files in the package sub-directories with src files.
Type “make package-diff” to list all differences between pairs of files in both the source directory and the package directory.