ADAPTING EXAMPLES TO DIFFERENT PYTHIA VERSIONS
-------------------------------------------------------------------------------

Currently this directory and 'testing' subdirecotry are adapted to pythia8.2
In order to use it with older pythia versions:

-------------------------------------------------------------------------------
0) Configuration
-------------------------------------------------------------------------------

NOTE: We are assuming the default configuration scripts are used. Changes
      to LCG scripts are analogous but nonetheless require different procedure.

- Use ./configure without providing pythia8 path (but provide all other paths)
- Files: make.inc ../configure.paths.sh (and .csh) will have
  empty PYTHIALOCATION variable. Provide this path by hand in both files.
- In ../configure.paths.sh (or .csh) provide PYTHIA8DATA location as:

  in .sh:  export PYTHIA8DATA=$PYTHIALOCATION/xmldoc
  in .csh: setenv PYTHIA8DATA "${PYTHIALOCATION}/xmldoc"

- source ../configure.paths.sh (or .csh)

-------------------------------------------------------------------------------
1) Adapting to pythia 8.180-8.185
-------------------------------------------------------------------------------
In code, replace:                     with:

#include "Pythia8Plugins/HepMC2.h"    #include "Pythia8/Pythia8ToHepMC.h"
pythia.stat()                         pythia.statistics()

In Makefile locate the PYTHIA_LIBS variable and update it with the list of
libraries for your version of pythia.

-------------------------------------------------------------------------------
2) Adapting to older pythia 8.1 versions
-------------------------------------------------------------------------------
In code, replace:                     with:

#include "Pythia8/Pythia.h"           #include "Pythia.h"
#include "Pythia8Plugins/HepMC2.h"    #include "HepMCInterface.h"
HepMC::Pythia8ToHepMC ToHepMC;        HepMC::I_Pythia8 ToHepMC;
pythia.stat()                         pythia.statistics()

In Makefile locate the PYTHIA_LIBS variable and update it with the list of
libraries for your version of pythia.

--
Last updated: 12 Mar 2016
