Debugging Tips

Printing Logs

ParaView Catalyst uses the standard logging system of ParaView to log its internal execution. To increase the verbosity of those specific logs, you can set the PARAVIEW_LOG_CATALYST_VERBOSITY environmental variable to INFO.

If you have issues prior to the actual ParaView Catalyst execution, you can set CATALYST_DEBUG to any non empty value. This will enable upstream logs about the Catalyst implementation loading procedure. You will see which implementation is actually loaded.

Debugging Runtime

Dealing with issues during the in situ analysis can be painful as you need to run the whole simulation code at each new try. Fortunately, two useful tools exist to help debugging your runtime.

First is the Catalyst Replay. With that, you need to run your simulation only once: it will write reusable data on your disk. Then, you only need to call the catalyst_replay executable to simulate a new run. Some environment variables may be useful here:

  • CATALYST_IMPLEMENTATION_PATHS and CATALYST_IMPLEMENTATION_NAME to point to the desired Catalyst implementation.

  • CATALYST_IMPLEMENTATION_PREFER_ENV to give priority to environment variable when looking for Catalyst implementation.

  • PYTHONPATH to override the python script directory, as Catalyst Replay will store an absolute path.

You can also emulate a simulation from a time series of VTK files, using the Catalyst Player. This is useful to prototype an analysis script from a representative dataset.