CDFJetCluPlugin.hh

//FJSTARTHEADER
// $Id$
//
// Copyright (c) 2005-2021, Matteo Cacciari, Gavin P. Salam and Gregory Soyez
//
//----------------------------------------------------------------------
// This file is part of FastJet.
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//  FastJet is free software; you can redistribute it and/or modify
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#ifndef __CDFJETCLUPLUGIN_HH__
#define __CDFJETCLUPLUGIN_HH__
 
#include "fastjet/JetDefinition.hh"
#include "fastjet/PseudoJet.hh"
#include <map>
#include "fastjet/internal/thread_safety_helpers.hh"  // helpers to write transparent code w&wo C++11 features
 
// questionable whether this should be in fastjet namespace or not...
 
FASTJET_BEGIN_NAMESPACE      // defined in fastjet/internal/base.hh
 
/// @ingroup plugins
/// \class CDFJetCluPlugin
/// Implementation of the JetClu algorithm from CDF (plugin for
/// fastjet-v2.1 upwards)
class CDFJetCluPlugin : public JetDefinition::Plugin {
public:
  /// a compact constructor
  CDFJetCluPlugin (double   cone_radius_in, 
                   double   overlap_threshold_in, 
                   double   seed_threshold_in = 1.0,
                   int      iratch_in = 1) : 
    _seed_threshold    ( seed_threshold_in    ),    
    _cone_radius       ( cone_radius_in       ),
    _adjacency_cut     (   2                  ),
    _max_iterations    ( 100                  ),
    _iratch            ( iratch_in            ),
    _overlap_threshold ( overlap_threshold_in )  {}
 
  /// a constructor that looks like the one provided by CDF
  CDFJetCluPlugin (double seed_threshold_in   ,  
                   double cone_radius_in      ,
                   int    adjacency_cut_in    ,
                   int    max_iterations_in   ,
                   int    iratch_in           ,
                   double overlap_threshold_in) :
    _seed_threshold    (seed_threshold_in    ),    
    _cone_radius       (cone_radius_in       ),
    _adjacency_cut     (adjacency_cut_in     ),
    _max_iterations    (max_iterations_in    ),
    _iratch            (iratch_in            ),
    _overlap_threshold (overlap_threshold_in )  {}
 
  // some functions to return info about parameters
  double seed_threshold    () const {return _seed_threshold    ;}
  double cone_radius       () const {return _cone_radius       ;}
  int    adjacency_cut     () const {return _adjacency_cut     ;}
  int    max_iterations    () const {return _max_iterations    ;}
  int    iratch            () const {return _iratch            ;}
  double overlap_threshold () const {return _overlap_threshold ;}
 
 
  // the things that are required by base class
  virtual std::string description () const;
  virtual void run_clustering(ClusterSequence &) const;
  /// the plugin mechanism's standard way of accessing the jet radius
  virtual double R() const {return cone_radius();}
                      
private:
 
  double _seed_threshold   ;
  double _cone_radius      ;
  int    _adjacency_cut    ;
  int    _max_iterations   ;
  int    _iratch           ;
  double _overlap_threshold;
 
  /// given a jet try inserting its energy into the map -- if that
  /// energy entry already exists, modify the jet infinitesimally so
  /// as ensure that the jet energy is unique
  void _insert_unique (PseudoJet & jet, std::map<double,int> & jetmap) const;
 
  static thread_safety_helpers::FirstTimeTrue _first_time;
 
  /// print a banner for reference to the 3rd-party code
  void _print_banner(std::ostream *ostr) const;
};
 
FASTJET_END_NAMESPACE      // defined in fastjet/internal/base.hh
 
#endif // __CDFJETCLUPLUGIN_HH__