Help with Pythia8 and Root

ROOT
1

Hi,

I’m new to using Root, and right now I’m trying to use Pythia8 in conjunction with Root. I’ve followed all of the README file instructions for both Root and Pythia thus far, but when I go to the $ROOTSYS/tutorials/pythia directory on my computer and enter root > .x pythia8.C, the output is:

Error in <TUnixSystem::DynamicPathName>: $PYTHIA8/lib/libpythia8[.so | .sl | .dl | .a | .dll] does not exist in /home/joey/Research/root/lib:/home/joey/Research/root/lib:/home/joey/Research/root/lib:/home/joey/Research/root/test:.:/home/joey/Research/root/lib::/home/joey/Research/root/cint/cint/stl Error in <TUnixSystem::DynamicPathName>: libEGPythia8[.so | .sl | .dl | .a | .dll] does not exist in /home/joey/Research/root/lib:/home/joey/Research/root/lib:/home/joey/Research/root/lib:/home/joey/Research/root/test:.:/home/joey/Research/root/lib::/home/joey/Research/root/cint/cint/stl Error: Symbol TPythia8 is not defined in current scope pythia8.C:32: Error: Symbol TPythia8 is not defined in current scope pythia8.C:32: Error: type TPythia8 not defined FILE:/home/joey/Research/root/tutorials/pythia/./pythia8.C LINE:32 Error: Invalid type 'TPythia8*' in declaration of 'pythia8' pythia8.C:32: *** Interpreter error recovered ***

Now, when I look at $PYTHIA8/lib, the libpythia8.so and libEGPythia8.so files are, in fact missing, and the only thing in this directory is an archive directory. I also tried moving the contents of this archive directory (libpythia8.a and liblhapdfdummy.a) into $PYTHIA8/lib, but then I get an invalid ELF header error message.

So my question is, why do I seem to be missing these files, and what should I be doing to make Pythia work with Root?

2

Ok, I’ve finally solved my own problem. I had to reconfigure pythia and remake it in order to get the libpythia.so file. And then I had to do the same in the root directory in order for it to make libEGPythia.so.

(I had reconfigured and remade root earlier, and I had reconfigured pythia to enable the shared libraries, but never remade pythia…The little mistakes are the most frustrating!)

Thanks for reading though!