Fork me on GitHub

Changes between Version 8 and Version 9 of WorkBook/Tutorials/Student


Ignore:
Timestamp:
09/08/19 18:36:16 (13 months ago)
Author:
mselvaggi
Comment:

--

Legend:

Unmodified
Added
Removed
Modified
  • WorkBook/Tutorials/Student

    v8 v9  
    7070
    7171
    72 In order to perform an event-loop with a more sophisticated event selection you will have to write a small python macro. This macro takes as input the {{{data.root}}} and produce an output file that contains a couple of histograms. Copy paste inside a file called {{{macro.py}}}, and run it via the command {{{python example.py histograms.root}}}.
    73 The {{{histograms.root}}} file can then be browsed as done before with the data file.
     72In order to perform an event-loop with a more sophisticated event selection you will have to write a small python macro. This macro takes as input the {{{data.root}}} and produce an output file that contains a couple of histograms. Download the file called {{{example.py}}}, and run it via the command {{{python example.py data.root hist_data.root}}}.
     73This will create a file called {{{hist_data.root}}} that can be browsed as done earlier with {{{data.root}}}.
    7474
    75 {{{
    76 # example event loop macro
    77 #!/usr/bin/env python
    7875
    79 import sys
    80 import ROOT
    81 
    82 if len(sys.argv) < 2:
    83   print " Usage: python macro.py data.root histograms.root"
    84   sys.exit(1)
    85 
    86 ROOT.gSystem.Load("libDelphes")
    87 
    88 try:
    89   ROOT.gInterpreter.Declare('#include "classes/SortableObject.h"')
    90   ROOT.gInterpreter.Declare('#include "classes/DelphesClasses.h"')
    91   ROOT.gInterpreter.Declare('#include "external/ExRootAnalysis/ExRootTreeReader.h"')
    92 except:
    93   pass
    94 
    95 inputFile = sys.argv[1]
    96 outputFile = sys.argv[2]
    97 
    98 # Create chain of root trees
    99 chain = ROOT.TChain("Delphes")
    100 chain.Add(inputFile)
    101 
    102 # Create object of class ExRootTreeReader
    103 treeReader = ROOT.ExRootTreeReader(chain)
    104 numberOfEntries = treeReader.GetEntries()
    105 
    106 # Get pointers to branches used in this analysis
    107 branchMuon = treeReader.UseBranch("Muon")
    108 branchJet = treeReader.UseBranch("Jet")
    109 
    110 # Book histograms
    111 histMuonMultiplicity = ROOT.TH1F("histMuonMultiplicity", "M_{recoil} [GeV]", 60, 100.0, 160.0)
    112 
    113 ptot = ROOT.TLorentzVector(0.,0.,0.,240.)
    114 # Loop over all events
    115 for entry in range(0, numberOfEntries):
    116   # Load selected branches with data from specified event
    117   treeReader.ReadEntry(entry)
    118 
    119   # If event contains at least 2 muons
    120   if branchMuon.GetEntries() > 1:
    121 
    122     mu1 = branchMuon.At(0)
    123     mu2 = branchMuon.At(1)
    124 
    125     pll = mu1.P4() + mu2.P4()
    126     ph = ptot - pll
    127 
    128     histMass.Fill(ph.M())
    129 
    130 out_root = ROOT.TFile(outputFile,"RECREATE")
    131 histMass.Write()
    132 }}}