===== Alternative Delphes instructions ===== 
==== Getting the software ==== 
  * You can either use the CMS "short-version" or the official version of Delphes. The CMS version contains Detector Cards for the Phase 2 detector layout with 140 PU and is recommended for our purposes.
  * In order to use Delphes you need to have ROOT installed. If you are using Scientific Linux 5 you can do this by setting up CMSSW (export SCRAM_ARCH=slc6_amd64_gcc481; cmsrel CMSSW_7_1_1; CMSSW_7_1_1/src/; cmsenv). If you are using SLC6 (t3ui12, t3ui15), you get compilation issues when using the CMS version and I recommend doing 'source /swshare/ROOT/thisroot.sh' at PSI. I recommend using SLC6 as this is needed for tkLayout (which we will use later).
  * Instrucions on how to set up the CMS Delphes version can be found [[https://twiki.cern.ch/twiki/bin/viewauth/CMS/HiggsWG/Phase2UpgradeStudies#Recommended_tag_and_version|here]]. A summary is given below. 

Fork the code from Git [[https://github.com/sethzenz/Delphes|here]] (or [[https://github.com/delphes/delphes|here]] for the official version) before cloning it to your local directory.

Do yourself a favour and be organized:
       mkdir $HOME/Phase2UpgradeStudies
       cd $HOME/Phase2UpgradeStudies

Clone your personal copy of the repository 
     git clone git@github.com:$USERNAME/Delphes
Make an alias to the main repository so you can fetch the latest changes
     git remote add official_delphes git@github.com:sethzenz/Delphes //or git@github.com:delphes/delphes for the official
Build
     cd Delphes/
     ./configure
     make
Congratulations, you are now ready to run Delphes! Depending on what type of input files you want to use, different codes are run. For HepMC files the syntax is
     ./DelphesHepMC Datacard.tcl output.root input.hepmc
Three arguments must be passed: the data card containing the detector configuration, the output file and the input MC file.\\
Try your setup with some Z->ee events and an example data card:
   wget http://cp3.irmp.ucl.ac.be/downloads/z_ee.hep.gz
   gunzip z_ee.hep.gz 
   ./DelphesSTDHEP examples/delphes_card_CMS.tcl delphes_output.root z_ee.hep

Examine the output:
   root -l
   gSystem->Load("libDelphes");
   TFile::Open("delphes_output.root");
   Delphes->Draw("Electron.PT");
   TBrowser browser;   
The different branches of the "Delphes" tree are listed [[ https://cp3.irmp.ucl.ac.be/projects/delphes/wiki/WorkBook/RootTreeDescription|here]]. For macro based analysis look in the [[https://cp3.irmp.ucl.ac.be/projects/delphes/browser/examples|examples/]] directory. Example1.C gives a simple example of histogram booking, event loop and histogram display. Check the [[https://cp3.irmp.ucl.ac.be/projects/delphes/wiki/WorkBook|WorkBook]] for more advanced examples.