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CircularRange.hh
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2 // $Id: CircularRange.hh 2577 2011-09-13 15:11:38Z salam $
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28 
29 
30 #ifndef __FASTJET_CIRCULARRANGE_HH__
31 #define __FASTJET_CIRCULARRANGE_HH__
32 
33 #include "fastjet/RangeDefinition.hh"
34 #include "fastjet/Error.hh"
35 
36 // for backwards compatibility: one should now use SelectorCircle,
37 // defined in fastjet/Selector.hh, instead CircularRange
38 #warning This file includes fastjet/CircularRange.hh, \
39 a deprecated FastJet header provided only for backward compatibility. \
40 This is not guaranteed to work in future releases of FastJet. \
41 From FastJet 3.0 onwards, please consider using Selector, defined in \
42 fastjet/Selector.hh, instead of RangeDefinition and, in particular, \
43 SelectorCircle instead of CircularRange.
44 
45 FASTJET_BEGIN_NAMESPACE // defined in fastjet/internal/base.hh
46 
47 class CircularRange : public fastjet::RangeDefinition {
48 public:
49  /// constructor
50  CircularRange() {_set_invalid_rapphi();}
51 
52  /// initialise CircularRange with a jet
53  CircularRange(const fastjet::PseudoJet & jet, double distance) {
54  _distance = distance;
55  _rapjet = jet.rap();
56  _phijet = jet.phi();
57  _total_area = fastjet::pi*_distance*_distance; }
58 
59  /// initialise CircularRange with a (rap,phi) point
60  CircularRange(double rap, double phi, double distance) {
61  _distance = distance;
62  _rapjet = rap;
63  _phijet = phi;
64  _total_area = fastjet::pi*_distance*_distance; }
65 
66  /// initialise CircularRange with just the radius parameter
67  CircularRange(double distance) {
68  _set_invalid_rapphi();
69  _distance = distance;
70  _total_area = fastjet::pi*_distance*_distance; }
71 
72  /// destructor
73  virtual ~CircularRange() {}
74 
75  /// return description of range
76  virtual inline std::string description() const {
77  std::ostringstream ostr;
78  ostr << "CircularRange: within distance "<< _distance << " of given jet or point." ;
79  return ostr.str(); }
80 
81  /// returns true since this range is localizable (i.e. set_position
82  /// does something meaningful)
83  virtual inline bool is_localizable() const { return true; }
84 
85  /// return bool according to whether (rap,phi) is in range
86  virtual inline bool is_in_range(double rap, double phi) const {
87  if (! _rapphi_are_valid()) {
88  throw Error("Circular range used without a center having being defined (use set_position())");
89  }
90  double deltaphi = _phijet - phi;
91  if ( deltaphi > pi) { deltaphi -= twopi; }
92  else if ( deltaphi < -pi) { deltaphi += twopi; }
93  bool inrange = ( (rap-_rapjet)*(rap-_rapjet) +
94  deltaphi*deltaphi <= _distance*_distance );
95  return inrange; }
96 
97  /// return the minimal and maximal rapidity of this range
98  virtual inline void get_rap_limits(double & rapmin, double & rapmax) const {
99  rapmin = _rapjet - _distance;
100  rapmax = _rapjet + _distance; }
101 
102 private:
103  double _distance;
104 
105  /// value for phi that marks it as invalid
106  const static double _invalid_phi = -1000.0;
107  /// set internal phi so as to mark things as invalid
108  void _set_invalid_rapphi() {_phijet = _invalid_phi;}
109  /// true if rap,phi are valid (tests only phi)
110  bool _rapphi_are_valid() const {return _phijet != _invalid_phi;}
111 };
112 
113 FASTJET_END_NAMESPACE
114 
115 #endif // __FASTJET_CIRCULARRANGE_HH__