Subtractor.hh

//STARTHEADER
// $Id: Subtractor.hh 2188 2011-05-31 15:44:46Z soyez $
//
// Copyright (c) 2005-2011, Matteo Cacciari, Gavin Salam and Gregory Soyez
//
//----------------------------------------------------------------------
// This file is part of FastJet.
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#ifndef __FASTJET_TOOLS_SUBTRACTOR_HH__
#define __FASTJET_TOOLS_SUBTRACTOR_HH__

#include <fastjet/tools/Transformer.hh> // to derive Subtractor from Transformer
#include <fastjet/tools/BackgroundEstimator.hh> // used as a ctor argument

FASTJET_BEGIN_NAMESPACE     // defined in fastjet/internal/base.hh


//----------------------------------------------------------------------
/// @ingroup tools
/// \class Subtractor
/// Class that helps performing jet background subtraction
///
/// This class is nothing but a transformer that makes use of the
/// BackgroundEstimator introduced above to subtract the background 
/// from the jet.
///
/// \section desc Options
/// 
/// The constructor takes as an argument a BackgroundEstimator.
///
/// \section input Input conditions
/// 
///  - the original jet must have area support (4-vector)
///
/// \section output Output/interface
/// 
///  The structure of the jet is not modified.
///
class Subtractor : public Transformer{
public:
  /// define a subtractor based on a BackgroundEstimator
  Subtractor(BackgroundEstimator * bge) : 
    _bge(bge) {}

  /// default dtor
  virtual ~Subtractor(){};

  /// returns a jet that's subtracted
  ///
  /// \param jet    the jet that is to be subtracted
  /// \return       the subtracted jet
  virtual PseudoJet result(const PseudoJet & jet) const;

  /// class description
  virtual std::string description() const{
    return "Subtractor";
  }

protected:
  /// the tool used to estimate the background
  /// if has to be mutable in case its underlying selector takes a reference jet
  mutable BackgroundEstimator * _bge;
};

FASTJET_END_NAMESPACE

#endif  // __FASTJET_TOOLS_SUBTRACTOR_HH__