FastJet 3.0.4
Dnn4piCylinder.hh
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00002 // $Id: Dnn4piCylinder.hh 2577 2011-09-13 15:11:38Z salam $
00003 //
00004 // Copyright (c) 2005-2011, Matteo Cacciari, Gavin P. Salam and Gregory Soyez
00005 //
00006 //----------------------------------------------------------------------
00007 // This file is part of FastJet.
00008 //
00009 //  FastJet is free software; you can redistribute it and/or modify
00010 //  it under the terms of the GNU General Public License as published by
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00017 //  include a citation to the FastJet paper.
00018 //
00019 //  FastJet is distributed in the hope that it will be useful,
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00022 //  GNU General Public License for more details.
00023 //
00024 //  You should have received a copy of the GNU General Public License
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00026 //----------------------------------------------------------------------
00027 //ENDHEADER
00028 
00029 
00030 #ifndef DROP_CGAL // in case we do not have the code for CGAL
00031 #ifndef __FASTJET_DNN4PICYLINDER_HH__
00032 #define __FASTJET_DNN4PICYLINDER_HH__
00033 
00034 #include "fastjet/internal/DynamicNearestNeighbours.hh"
00035 #include "fastjet/internal/DnnPlane.hh"
00036 #include "fastjet/internal/numconsts.hh"
00037 
00038 FASTJET_BEGIN_NAMESPACE      // defined in fastjet/internal/base.hh
00039 
00040 /// \if internal_doc
00041 /// @ingroup internal
00042 /// \class Dnn4piCylinder
00043 /// class derived from DynamicNearestNeighbours that provides an
00044 /// implementation for the surface of cylinder (using two copies of
00045 /// DnnPlane, one running from 0--2pi, the other from pi--3pi).
00046 /// \endif
00047 class Dnn4piCylinder : public DynamicNearestNeighbours {
00048  public:
00049   /// empty initaliser
00050   Dnn4piCylinder() {}
00051 
00052   /// Initialiser from a set of points on an Eta-Phi plane, where
00053   /// eta can have an arbitrary ranges and phi must be in range
00054   /// 0 <= phi < 2pi
00055   Dnn4piCylinder(const std::vector<EtaPhi> &, const bool & verbose = false );
00056 
00057   /// Returns the index of  the nearest neighbour of point labelled
00058   /// by ii (assumes ii is valid)
00059   int NearestNeighbourIndex(const int & ii) const ;
00060 
00061   /// Returns the distance to the nearest neighbour of point labelled
00062   /// by index ii (assumes ii is valid)
00063   double NearestNeighbourDistance(const int & ii) const ;
00064 
00065   /// Returns true iff the given index corresponds to a point that
00066   /// exists in the DNN structure (meaning that it has been added, and
00067   /// not removed in the meantime)
00068   bool Valid(const int & index) const;
00069 
00070   void RemoveAndAddPoints(const std::vector<int> & indices_to_remove,
00071                           const std::vector<EtaPhi> & points_to_add,
00072                           std::vector<int> & indices_added,
00073                           std::vector<int> & indices_of_updated_neighbours);
00074 
00075   ~Dnn4piCylinder();
00076 
00077  private:
00078 
00079   bool _verbose;
00080 
00081   // NB: we define POINTERS here because the initialisation gave
00082   //     us problems (things crashed!), perhaps because in practice
00083   //     we were making a copy without being careful and defining
00084   //     a proper copy constructor.
00085   DnnPlane * _DNN1, * _DNN2;
00086 
00087   /// given a phi value in the 0--2pi range return one 
00088   /// in the pi--3pi range.
00089   inline EtaPhi _remap_phi(const EtaPhi & point) {
00090     double phi = point.second;
00091     if (phi < pi) { phi += twopi ;}
00092     return EtaPhi(point.first, phi);}
00093 
00094 };
00095 
00096 
00097 // here follow some inline implementations of the simpler of the
00098 // functions defined above
00099 
00100 inline int Dnn4piCylinder::NearestNeighbourIndex(const int & current) const {
00101   return (_DNN1->NearestNeighbourDistance(current) < 
00102           _DNN2->NearestNeighbourDistance(current)) ? 
00103     _DNN1->NearestNeighbourIndex(current) : 
00104     _DNN2->NearestNeighbourIndex(current) ; 
00105 }
00106 
00107 inline double Dnn4piCylinder::NearestNeighbourDistance(const int & current) const {
00108   return (_DNN1->NearestNeighbourDistance(current) < 
00109           _DNN2->NearestNeighbourDistance(current)) ? 
00110     _DNN1->NearestNeighbourDistance(current) : 
00111     _DNN2->NearestNeighbourDistance(current) ; 
00112 }
00113 
00114 inline bool Dnn4piCylinder::Valid(const int & index) const {
00115   return (_DNN1->Valid(index) && _DNN2->Valid(index));
00116 }
00117 
00118 
00119 inline Dnn4piCylinder::~Dnn4piCylinder() {
00120   delete _DNN1; 
00121   delete _DNN2;
00122 }
00123 
00124 
00125 FASTJET_END_NAMESPACE
00126 
00127 #endif //  __FASTJET_DNN4PICYLINDER_HH__
00128 #endif //  DROP_CGAL 
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