SISCone  3.0.5
siscone.cpp
1 // File: siscone.cpp //
3 // Description: source file for the main SISCone class //
4 // This file is part of the SISCone project. //
5 // For more details, see http://projects.hepforge.org/siscone //
6 // //
7 // Copyright (c) 2006 Gavin Salam and Gregory Soyez //
8 // //
9 // This program is free software; you can redistribute it and/or modify //
10 // it under the terms of the GNU General Public License as published by //
11 // the Free Software Foundation; either version 2 of the License, or //
12 // (at your option) any later version. //
13 // //
14 // This program is distributed in the hope that it will be useful, //
15 // but WITHOUT ANY WARRANTY; without even the implied warranty of //
16 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the //
17 // GNU General Public License for more details. //
18 // //
19 // You should have received a copy of the GNU General Public License //
20 // along with this program; if not, write to the Free Software //
21 // Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA //
22 // //
23 // $Revision:: 403 $//
24 // $Date:: 2016-05-19 16:52:05 +0200 (Thu, 19 May 2016) $//
26 
27 #include "config.h"
28 #include "ranlux.h"
29 #include "momentum.h"
30 #include "defines.h"
31 #include "siscone.h"
32 #include "siscone_error.h"
33 #include <iostream>
34 #include <sstream>
35 #include <iomanip>
36 
37 namespace siscone{
38 using namespace std;
39 
40 /***************************************************************
41  * Csiscone implementation *
42  * final class: gather everything to compute the jet contents. *
43  * *
44  * This is the class user should use. *
45  * It computes the jet contents of a list of particles *
46  * given a cone radius and a threshold for splitting/merging. *
47  ***************************************************************/
48 
49 // default ctor
50 //--------------
52  rerun_allowed = false;
53 }
54 
55 // default dtor
56 //--------------
58  rerun_allowed = false;
59 }
60 
61 bool Csiscone::init_done=false;
62 std::ostream* Csiscone::_banner_ostr = &cout;
63 
64 /*
65  * compute the jets from a given particle set doing multiple passes
66  * such pass N looks for jets among all particles not put into jets
67  * during previous passes.
68  * - _particles list of particles
69  * - _radius cone radius
70  * - _f shared energy threshold for splitting&merging
71  * - _n_pass_max maximum number of runs
72  * - _ptmin minimum pT of the protojets
73  * - _split_merge_scale the scale choice for the split-merge procedure
74  * NOTE: using pt leads to IR unsafety for some events with momentum
75  * conservation. So we strongly advise not to change the default
76  * value.
77  * return the number of jets found.
78  **********************************************************************/
79 int Csiscone::compute_jets(vector<Cmomentum> &_particles, double _radius, double _f,
80  int _n_pass_max, double _ptmin,
81  Esplit_merge_scale _split_merge_scale){
82  _initialise_if_needed();
83 
84  // run some general safety tests (NB: f will be checked in split-merge)
85  if (_radius <= 0.0 || _radius >= 0.5*M_PI) {
86  ostringstream message;
87  message << "Illegal value for cone radius, R = " << _radius
88  << " (legal values are 0<R<pi/2)";
89  throw Csiscone_error(message.str());
90  }
91 
92 
93 
94  ptcomparison.split_merge_scale = _split_merge_scale;
95  partial_clear(); // make sure some things are initialised properly
96 
97  // init the split_merge algorithm with the initial list of particles
98  // this initialises particle list p_left of remaining particles to deal with
99  init_particles(_particles);
100 
101  bool finished = false;
102 
103  rerun_allowed = false;
104  protocones_list.clear();
105 
106 #ifdef DEBUG_STABLE_CONES
107  nb_hash_cones_total = 0;
108  nb_hash_occupied_total = 0;
109 #endif
110 
111  do{
112  // initialise stable_cone finder
113  // here we use the list of remaining particles
114  // AFTER COLLINEAR CLUSTERING !!!!!!
115  Cstable_cones::init(p_uncol_hard);
116 
117  // get stable cones
118  if (get_stable_cones(_radius)){
119  // we have some new protocones; add them to candidates
120  // Note that add_protocones has to be called first
121  // if we want the 4-vect components to be available
122  // on top of eta and phi.
123  add_protocones(&protocones, R2, _ptmin);
124  protocones_list.push_back(protocones);
125 #ifdef DEBUG_STABLE_CONES
126  nb_hash_cones_total += nb_hash_cones;
127  nb_hash_occupied_total += nb_hash_occupied;
128 #endif
129  } else {
130  // no new protocone: leave
131  finished=true;
132  }
133 
134  _n_pass_max--;
135  } while ((!finished) && (n_left>0) && (_n_pass_max!=0));
136 
137  rerun_allowed = true;
138 
139  // split & merge
140  return perform(_f, _ptmin);
141 }
142 
143 
144 /*
145  * compute the jets from a given particle set doing multiple passes
146  * such pass N looks for jets among all particles not put into jets
147  * during previous passes.
148  * - _particles list of particles
149  * - _radius cone radius
150  * - _n_pass_max maximum number of runs
151  * - _ptmin minimum pT of the protojets
152  * - _ordering_scale the ordering scale to decide which stable
153  * cone is removed
154  * return the number of jets found.
155  **********************************************************************/
156 int Csiscone::compute_jets_progressive_removal(vector<Cmomentum> &_particles, double _radius,
157  int _n_pass_max, double _ptmin,
158  Esplit_merge_scale _ordering_scale){
159  _initialise_if_needed();
160 
161  // run some general safety tests (NB: f will be checked in split-merge)
162  if (_radius <= 0.0 || _radius >= 0.5*M_PI) {
163  ostringstream message;
164  message << "Illegal value for cone radius, R = " << _radius
165  << " (legal values are 0<R<pi/2)";
166  throw Csiscone_error(message.str());
167  }
168 
169  ptcomparison.split_merge_scale = _ordering_scale;
170  partial_clear(); // make sure some things are initialised properly
171 
172  // init the split_merge algorithm with the initial list of particles
173  // this initialises particle list p_left of remaining particles to deal with
174  //
175  // this stores the "processed" particles in p_uncol_hard
176  init_particles(_particles);
177  jets.clear();
178 
179  bool unclustered_left;
180  rerun_allowed = false;
181  protocones_list.clear();
182 
183  do{
184  //cout << n_left << " particle left" << endl;
185 
186  // initialise stable_cone finder
187  // here we use the list of remaining particles
188  // AFTER COLLINEAR CLUSTERING !!!!!!
189  Cstable_cones::init(p_uncol_hard);
190 
191  // get stable cones (stored in 'protocones')
192  unclustered_left = get_stable_cones(_radius);
193 
194  // add the hardest stable cone to the list of jets
195  if (add_hardest_protocone_to_jets(&protocones, R2, _ptmin)) break;
196 
197  _n_pass_max--;
198  } while ((unclustered_left) && (n_left>0) && (_n_pass_max!=0));
199 
200  // split & merge
201  return jets.size();
202 }
203 
204 
205 /*
206  * recompute the jets with a different overlap parameter.
207  * we use the same particles and R as in the preceeding call.
208  * - _f shared energy threshold for splitting&merging
209  * - _ptmin minimum pT of the protojets
210  * - _split_merge_scale the scale choice for the split-merge procedure
211  * NOTE: using pt leads to IR unsafety for some events with momentum
212  * conservation. So we strongly advise not to change the default
213  * value.
214  * return the number of jets found, -1 if recomputation not allowed.
215  ********************************************************************/
216 int Csiscone::recompute_jets(double _f, double _ptmin,
217  Esplit_merge_scale _split_merge_scale){
218  if (!rerun_allowed)
219  return -1;
220 
221  ptcomparison.split_merge_scale = _split_merge_scale;
222 
223  // restore particle list
224  partial_clear();
225  init_pleft();
226 
227  // initialise split/merge algorithm
228  unsigned int i;
229  for (i=0;i<protocones_list.size();i++)
230  add_protocones(&(protocones_list[i]), R2, _ptmin);
231 
232  // split & merge
233  return perform(_f, _ptmin);
234 }
235 
236 // ensure things are initialised
237 void Csiscone::_initialise_if_needed(){
238  // initialise random number generator
239  if (init_done) return;
240 
241  // initialise random number generator
242  ranlux_init();
243 
244  // do not do this again
245  init_done=true;
246 
247  // print the banner
248  if (_banner_ostr != 0){
249  ios::fmtflags flags_to_restore(_banner_ostr->flags());
250 
251  (*_banner_ostr) << "#ooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooo" << endl;
252  (*_banner_ostr) << "# SISCone version " << setw(28) << left << siscone_version() << "o" << endl;
253  (*_banner_ostr) << "# http://projects.hepforge.org/siscone o" << endl;
254  (*_banner_ostr) << "# o" << endl;
255  (*_banner_ostr) << "# This is SISCone: the Seedless Infrared Safe Cone Jet Algorithm o" << endl;
256  (*_banner_ostr) << "# SISCone was written by Gavin Salam and Gregory Soyez o" << endl;
257  (*_banner_ostr) << "# It is released under the terms of the GNU General Public License o" << endl;
258  (*_banner_ostr) << "# o" << endl;
259  (*_banner_ostr) << "# A description of the algorithm is available in the publication o" << endl;
260  (*_banner_ostr) << "# JHEP 05 (2007) 086 [arXiv:0704.0292 (hep-ph)]. o" << endl;
261  (*_banner_ostr) << "# Please cite it if you use SISCone. o" << endl;
262  (*_banner_ostr) << "#ooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooo" << endl;
263  (*_banner_ostr) << endl;
264 
265  _banner_ostr->flush();
266  _banner_ostr->flags(flags_to_restore);
267  }
268 }
269 
270 // finally, a bunch of functions to access to
271 // basic information (package name, version)
272 //---------------------------------------------
273 
274 /*
275  * return SISCone package name.
276  * This is nothing but "SISCone", it is a replacement to the
277  * SISCONE_PACKAGE_NAME string defined in config.h and which is not
278  * guaranteed to be public.
279  * return the SISCone name as a string
280  */
281 string siscone_package_name(){
282  return SISCONE_PACKAGE_NAME;
283 }
284 
285 /*
286  * return SISCone version number.
287  * return a string of the form "X.Y.Z" with possible additional tag
288  * (alpha, beta, devel) to mention stability status
289  */
290 string siscone_version(){
291  return SISCONE_VERSION;
292 }
293 
294 }
class corresponding to errors that will be thrown by siscone
Definition: siscone_error.h:38
int compute_jets(std::vector< Cmomentum > &_particles, double _radius, double _f, int _n_pass_max=0, double _ptmin=0.0, Esplit_merge_scale _split_merge_scale=SM_pttilde)
compute the jets from a given particle set.
Definition: siscone.cpp:79
int recompute_jets(double _f, double _ptmin=0.0, Esplit_merge_scale _split_merge_scale=SM_pttilde)
recompute the jets with a different overlap parameter.
Definition: siscone.cpp:216
~Csiscone()
default dtor
Definition: siscone.cpp:57
int compute_jets_progressive_removal(std::vector< Cmomentum > &_particles, double _radius, int _n_pass_max=0, double _ptmin=0.0, Esplit_merge_scale _ordering_scale=SM_pttilde)
compute the jets from a given particle set.
Definition: siscone.cpp:156
static bool init_done
check random generator initialisation
Definition: siscone.h:120
Csiscone()
default ctor
Definition: siscone.cpp:51
void init(std::vector< Cmomentum > &_particle_list)
initialisation
Definition: protocones.cpp:114