1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
|
//STARTHEADER
// $Id: JadePlugin.cc 2577 2011-09-13 15:11:38Z salam $
//
// Copyright (c) 2007-2011, Matteo Cacciari, Gavin P. Salam and Gregory Soyez
//
//----------------------------------------------------------------------
// This file is part of FastJet.
//
// FastJet is free software; you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation; either version 2 of the License, or
// (at your option) any later version.
//
// The algorithms that underlie FastJet have required considerable
// development and are described in hep-ph/0512210. If you use
// FastJet as part of work towards a scientific publication, please
// include a citation to the FastJet paper.
//
// FastJet is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with FastJet. If not, see <http://www.gnu.org/licenses/>.
//----------------------------------------------------------------------
//ENDHEADER
// fastjet stuff
#include "fastjet/ClusterSequence.hh"
#include "fastjet/JadePlugin.hh"
#include <iostream>
//#include "fastjet/internal/ClusterSequence_N2.icc"
#include "fastjet/NNH.hh"
// other stuff
#include <vector>
#include <sstream>
#include <limits>
using namespace std;
FASTJET_BEGIN_NAMESPACE // defined in fastjet/internal/base.hh
//----------------------------------------------------------------------
/// class to help run a JADE algorithm
class JadeBriefJet {
public:
void init(const PseudoJet & jet) {
double norm = 1.0/sqrt(jet.modp2());
nx = jet.px() * norm;
ny = jet.py() * norm;
nz = jet.pz() * norm;
rt2E = sqrt(2.0)*jet.E();
}
double distance(const JadeBriefJet * jet) const {
double dij = 1 - nx*jet->nx
- ny*jet->ny
- nz*jet->nz;
dij *= rt2E*jet->rt2E;
return dij;
}
double beam_distance() const {
return numeric_limits<double>::max();
}
private:
double rt2E, nx, ny, nz;
};
//----------------------------------------------------------------------
string JadePlugin::description () const {
ostringstream desc;
desc << "e+e- JADE algorithm plugin";
return desc.str();
}
//----------------------------------------------------------------------
void JadePlugin::run_clustering(ClusterSequence & cs) const {
int njets = cs.jets().size();
NNH<JadeBriefJet> nnh(cs.jets());
// if testing against Hoeth's implementation, need to rescale the
// dij by Q^2.
//double Q2 = cs.Q2();
while (njets > 0) {
int i, j, k;
double dij = nnh.dij_min(i, j);
if (j >= 0) {
cs.plugin_record_ij_recombination(i, j, dij, k);
nnh.merge_jets(i, j, cs.jets()[k], k);
} else {
double diB = cs.jets()[i].E()*cs.jets()[i].E(); // get new diB
cs.plugin_record_iB_recombination(i, diB);
nnh.remove_jet(i);
}
njets--;
}
}
FASTJET_END_NAMESPACE // defined in fastjet/internal/base.hh
|
