fullsimlight: Pythia random number seeds ignored.
Hi, this may not really be an issue because I can see that the source as it comes is setup to always use the same seed, but I also see from the comments in PythiaPrimaryGeneratorAction.hh/cc that it is supposed to be possible?
I have changed PythiaPrimaryGeneratorAction.hh so that
PythiaPrimaryGeneratorAction(int seeding = 0);
and by setting fPythia.readString("Random:seed = 0");
in PythiaPrimaryGeneratorAction.cc, which according to the comments should set a random seed by the system clock, but it does not. If I run my simulation I always get the same initial momenta for my events.
I have tried many different things, commenting everything out in hopes to get it to read my random numbers from my pythia command file. I have setup random number generator in the code and used it for Random:seed, I have ran the simulation with 1 seed, change the seed, recompiles, re-ran. In the GeneratePrimaries(G4Event *event) method I've changed
if (fSeeding == 0) { fPythia.rndm.init(event->GetEventID()+1); }
so that a random number is used instead of this. No matter what I do I get the same result, however if I take my command file and run it in pythia and print out a hepmc file, I can get different results when I change the seed.
Again, I know it's not necessarily an intended function of the program, but is there any way to enable a random seed and pass it to pythia, so that I don't get the same result every time I run?