EXAMPLE_CUTS.cc

Go to the documentation of this file.

// -*- C++ -*-
#include "Rivet/Analysis.hh"
#include "Rivet/Projections/FinalState.hh"
#include "Rivet/Cuts.hh"

namespace Rivet {


  /// @brief Just measures a few random things as an example.
  class EXAMPLE_CUTS : public Analysis {
  public:

    /// Constructor
    EXAMPLE_CUTS()
      : Analysis("EXAMPLE_CUTS")
    {
      // No counters etc. to initialise, hence nothing to do here!
    }


    /// @name Analysis methods
    //@{

    /// Set up projections and book histograms
    void init() {
      // Projections
      const FinalState cnfs( EtaIn(-4, 4) );
      addProjection(cnfs, "FS");

      // Histograms
      _histPt         = bookHisto1D("pT", 30, 0, 30);
      _histMass       = bookHisto1D("Mass", 20, 0, 1);

    }


    /// Do the analysis
    void analyze(const Event& event) {
      // Make sure to always include the event weight in histogram fills!
      const double weight = event.weight();

      const Particles ps = applyProjection<FinalState>(event, "FS").particlesByPt();

      Cut ptcut = Range( Cuts::pT, 5, 20 );
      Cut masscut = Range( Cuts::mass, 0, 0.2);
      Cut combine = ptcut & masscut; //Possible to combine cuts

      foreach(const Particle& p, ps) {
        if ( ptcut->accept(p) ) 
      _histPt->fill(p.momentum().pT(), weight);
    if ( combine->accept(p) ) 
      _histMass->fill(p.momentum().mass(), weight);
      }

    }


    /// Finalize
    void finalize() {
      normalize(_histPt);
      normalize(_histMass);
    }

    //@}


  private:

    //@{
    /// Histograms
    Histo1DPtr _histPt, _histMass;
    //@}

  };



  // The hook for the plugin system
  DECLARE_RIVET_PLUGIN(EXAMPLE_CUTS);

}