Transformer.hh

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#ifndef __FASTJET_TRANSFORMER_HH__
#define __FASTJET_TRANSFORMER_HH__
 
#include "fastjet/PseudoJet.hh"
#include "fastjet/FunctionOfPseudoJet.hh"
#include "fastjet/PseudoJetStructureBase.hh"
 
FASTJET_BEGIN_NAMESPACE      // defined in fastjet/internal/base.hh
 
// forward declarations of what we will have down here
class Transformer;
 
/// @ingroup tools_generic
/// \class Transformer
///
/// Base (abstract) class for a jet transformer.
///
/// A transformer, when it acts on a jet, returns a modified version
/// of that jet, one that may have a different momentum and/or
/// different internal structure.
///
/// The typical usage of a class derived from Transformer is
/// \code
///   SomeTransformer transformer(...);
///   PseudoJet transformed_jet = transformer(original_jet);
///   // or
///   vector<PseudoJet> transformed_jets = transformer(original_jets);
/// \endcode
///
/// For many transformers, the transformed jets have
/// transformer-specific information that can be accessed through the
///
/// \code
///   transformed_jet.structure_of<SomeTransformer>().transformer_specific_info();
/// \endcode
///
/// See the description of the Filter class for a more detailed usage
/// example. See the FastJet manual to find out how to implement
/// new transformers.
///
class Transformer : public FunctionOfPseudoJet<PseudoJet>{
public:
  /// default ctor
  Transformer(){}
 
  /// default dtor
  virtual ~Transformer(){}
 
  /// the result of the Transformer acting on the PseudoJet.
  /// this _has_ to be overloaded in derived classes
  /// \param original   the PseudoJet input to the Transformer
  virtual PseudoJet result(const PseudoJet & original) const = 0;
 
  /// This should be overloaded to return a description of the
  /// Transformer
  virtual std::string description() const = 0;
 
  /// A typedef that is needed to ensure that the
  /// PseudoJet::structure_of() template function works
  //
  // Make sure you reimplement this appropriately in any
  // derived classes
  typedef PseudoJetStructureBase StructureType;
};
 
FASTJET_END_NAMESPACE      // defined in fastjet/internal/base.hh
 
#endif // __FASTJET_TRANSFORMER_HH__