PostProcessing Ligghts

This software provides many post-processing functions to handle data simulated using the Discrete Element Modelling software Liggghts. It started quite a while ago and has accumulated years of code, so no everything is relevent of working. Nevertheless, it can be quite powerful and useful.

Getting started

Compiling

These instruction are provided with a linux os in mind. Compiling on other operating systems is possible, but your milage may vary.

• Clone the repository: git clone https://github.com/Franzzzzzzzz/PostProcessingLiggghts

• Move there: cd PostProcessingLiggghts

• Create a build folder: mkdir build && cd build

• Prepare the compilation: cmake ..

  • MATLAB support: if you want to support writing the data in Matlab format, cmake needs to be able to find the matlab library. This is done by adjusting the variable Matlab_ROOT_DIR to your system installation.

  • Other useful library: libtif, zlib, boost. Some of these may allow compilation even when not found, other won't.

  • Language: for historical reason, the default language of the software is a mix of mostly French and English. If you want English only, set the language variable in cmake to en_AU.UTF-8.

• Build: make

• You should now have an executable called PostProcessing in the build folder.

Using PostProcessing

The program runs in command line only. The last argument is always a dump from Liggghts. The argument before the last one can be a dump from ligghts of the particle positions if the last argument is a dump of contact forces.

Examples:

• Get help: PostProcessing --help null

• Create vtk files from dump files: PostProcessing --dump2vtk --W '[vtk]def,v,type,radius' dump.test

• Create a vtk with the contact forces: PostProcessing --dump2vtk --chainforce --W '[vtk]def,cff' dump.test dump.force

• Create a vtk with orientation information for superquadric/ellipsoidal particles, to use with the TensorGlyph filter in Paraview (requires to export the quaternion components quat1-4): PostProcessing --dump2vtk --superquadric 0.001 0.001 0.002 --W '[+vtk]def,v,orient' dump.test

• Coarse-grain particle data: PostProcessing --coarse-graining 3 4 5 --W "[vtk]v,phi" dump.test

• Coarse-grain contact data: PostProcessing --coarse-graining 3 4 5 --use-box -0.2 0.2 -0.1 0.1 1.2 1.5 --chainforce --W "[vtk]sigmatot" --w/kinetic dump.particles dump.contact