Setting environment for FissionFragment GEANT4 example


I am trying to run one of GEANT4 extended examples, which is FissionFragment. However, it is asking me to set an environment before running. I do not know how to do that honestly. Here is a capture:


How to set the environment above? Sorry it might seem very easy but I am a new user.

Figured it out. It was so simple: export G4NEU…=“geant4 location/data”

How did you export those variable?
I can’t find G4NEU… at my geant4_location/data.
Should I make it? Or download some other thing?

Look at the name string quoted in the screenshot originally posted. The author wrote “G4NEU…” as an abbreviation for “G4NEUTRONHP_PRODUCE_FISSION_FRAGMENTS”.

Oh, I knew that G4NEU… is an abbreviation for G4NEUTRONHP_PRODUCE_FISSION_FRAGMENTS.
What I meant was I can’t find the “G4NEUTRONHP_PRODUCE_FISSION_FRAGMENTS” at my geant4_location/data.
Anyway, thank you for your reply! :slight_smile:

That’s not going to be the name of the file. It’s the name of the envvar. Looking into the code ( it looks like it does not need to have a value at all, it just has to exist:


So you should be able to set


and get the fragments produced as secondaries.

Thank you for your reply, mkelsey. It was really helpfull!

in examples/extended/hadronic/Hadr03 you will find (or csh) which illustrates how to set such environment variables.

Thank you for your specific comment maire. :slight_smile: