Pythia `numberOfEvents` error: variable recognized, but its value is out of range

[ikrommyd]

I was going through the hands-on tutotial under: https://github.com/ajgilbert/EFT-HandsOn/ and at the rivet analysis part, when I'd run python scripts/run_gridpack.py --gridpack gridpack_Higgs-VBF.tar.gz -s 1 -e 5000 -p HiggsVBF -o test-Higgs-VBF, pythia would give the following error log:

[ikrommyd@lxplus933 EFT-HandsOn]$ tail -f /tmp/ikrommyd/gridpack_run_1/madevent/Events/GridRun/tag_1_pythia8.log
 PYTHIA Abort from Pythia::init: some user settings did not make sense
Considering 1000 events. Make sure that there is enough events in the input event files, otherwise  normalization is likely to be wrong.



Start generating events
 PYTHIA Error in Settings::mode: value is out of range Main:numberOfEvents

 PYTHIA Error: variable recognized, but its value is out of range:
   Main:numberOfEvents      = -1

If I change the numberOfEvents to let's say 5000 in pythia8_card.dat, it works fine.
I noticed that the cards under the cards directory set Main:numberOfEvents = -1 and I was wondering if this should be changed since pythia specifies that

mode  Main:numberOfEvents   (default = 1000; minimum = 0)
The number of events to be generated.

under https://pythia.org/latest-manual/MainProgramSettings.html or whether there's something else I'm missing. I'm very new with event generators and EFT tools.

[ajgilbert]

Hi @ikrommyd yes I've also seen this recently. I think the MG authors have updated the PY8 version that gets downloaded internally, and -1 is no longer accepted as the default - instead we should put 0. This can be fixed by setting that in the pythia8_card.dat in our EFT2Obs cards/[X] directory before running the make_gridpack.sh step. We will try and develop a fix that takes care of that automatically.