12. Executables and Scripts

12.1. openmc

Once you have a model built (see Basics of Using OpenMC), you can either run the openmc executable directly from the directory containing your XML input files, or you can specify as a command-line argument the directory containing the XML input files.

Warning

OpenMC models should be treated as code, and it is important to be careful with code from untrusted sources.

For example, if your XML input files are in the directory /home/username/somemodel/, one way to run the simulation would be:

cd /home/username/somemodel
openmc

Alternatively, you could run from any directory:

openmc /home/username/somemodel

Note that in the latter case, any output files will be placed in the present working directory which may be different from /home/username/somemodel. openmc accepts the following command line flags:

-c, --volume

Run in stochastic volume calculation mode

-e, --event

Run using event-based parallelism

-g, --geometry-debug

Run in geometry debugging mode, where cell overlaps are checked for after each move of a particle

-n, --particles N

Use N particles per generation or batch

-p, --plot

Run in plotting mode

-r, --restart file

Restart a previous run from a state point or a particle restart file

-s, --threads N

Run with N OpenMP threads

-t, --track

Write tracks for all particles (up to max_tracks)

-v, --version

Show version information

-h, --help

Show help message

Note

If you’re using the Python API, openmc.run() is equivalent to running openmc from the command line.