[Rivet] possibility to add (hadd) yoda files, and running rivet on lxplus batch jobs

[Raghav Kunnawalkam Elayavalli]

Hi Rivet Experts, 

My current analysis has exploded into quite the complicated one leading to a large run time ~25 seconds per 100 events. It would be very useful if i can submit jobs to run this in parallel say 100 job running over 1000 events each. In leu of this requirement, i would need to add the output yoda files together similar to the hadd script that does root files. 
Im also having several difficulties with the proper python environment at the node where my batch jobs end up (for rivet -a ANALYSIS input.hepmc). 
this is what i used in my rivet installation on lxplus in the rivet-bootstrap-lcg 
SETUPCMD_PYTHON="source $LCGDIR/Python/2.7.10/x86_64-slc6-gcc48-opt/Python-env.sh"
and this is what i set in my job 
source /cvmfs/sft.cern.ch/lcg/releases/LCG_84/Python/2.7.10/x86_64-slc6-gcc48-opt/Python-env.sh
when i submit a job with this python and rivet setup, i get a following error


@(#)CERN job starter $Date: 2010/06/23 14:22:16 $
Working directory is </pool/lsf/rkunnawa/809932193> on <b64f2daace.cern.ch>
Started running the job

this error is for sourcing that python env. 

'import site' failed; use -v for traceback
Traceback (most recent call last):
  File "/cvmfs/sft.cern.ch/lcg/releases/LCG_84/lcgenv/1.3.2.1/x86_64-centos7-gcc49-dbg/lcgenv", line 11, in <module>
    import os
ImportError: No module named os

# output of which python: 
/usr/bin/python

these are for the following error messages when it comes to the rivet -a 
'import site' failed; use -v for traceback
Traceback (most recent call last):
  File "/afs/cern.ch/work/r/rkunnawa/JEWEL/local/bin/rivet", line 20, in <module>
    import os, sys
ImportError: No module named os
'import site' failed; use -v for traceback
Traceback (most recent call last):
  File "/afs/cern.ch/work/r/rkunnawa/JEWEL/local/bin/rivet-mkhtml", line 17, in <module>
    import rivet, sys, os
ImportError: No module named rivet


Cheers
Raghav