HepMC3 event record library
HEPEVT_Helpers.h
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1// -*- C++ -*-
2//
3// This file is part of HepMC
4// Copyright (C) 2014-2021 The HepMC collaboration (see AUTHORS for details)
5//
6#ifndef HEPEVT_HELPERS_H
7#define HEPEVT_HELPERS_H
8/**
9 * @file HEPEVT_Helpers.h
10 * @brief Helper functions used to manipulate with HEPEVT block
11 *
12 */
13#if defined(WIN32)&&(!defined(HEPMC3_NO_EXPORTS))
14#if defined(HepMC3_EXPORTS)
15#define HEPMC3_EXPORT_API __declspec(dllexport)
16#else
17#define HEPMC3_EXPORT_API __declspec(dllimport)
18#endif
19#else
20#define HEPMC3_EXPORT_API
21#endif
22#include <algorithm>
23#include <map>
24
25#include "HepMC3/GenEvent.h"
26#include "HepMC3/GenParticle.h"
27#include "HepMC3/GenVertex.h"
28namespace HepMC3
29{
30
31/** @struct HEPEVT_Templated
32 * @brief C structure representing Fortran common block HEPEVT
33 * T. Sjöstrand et al., "A proposed standard event record",
34 * in `Z physics at LEP 1', eds. G. Altarelli, R. Kleiss and C. Verzegnassi,
35 * Geneva, Switzerland, September 4-5, 1989, CERN 89-08 (Geneva, 1989), Vol. 3, p. 327
36 * Disk representation is given by Fortran WRITE/READ format.
37 */
38template <int max_particles, typename momentum_type = double>
40{
41 int nevhep; //!< Event number
42 int nhep; //!< Number of entries in the event
43 int isthep[max_particles]; //!< Status code
44 int idhep [max_particles]; //!< PDG ID
45 int jmohep[max_particles][2]; //!< Position of 1st and 2nd (or last!) mother
46 int jdahep[max_particles][2]; //!< Position of 1nd and 2nd (or last!) daughter
47 momentum_type phep [max_particles][5]; //!< Momentum: px, py, pz, e, m
48 momentum_type vhep [max_particles][4]; //!< Time-space position: x, y, z, t
49};
50
51/** @struct HEPEVT_Pointers
52 * @brief C structure representing Fortran common block HEPEVT
53 * T. Sjöstrand et al., "A proposed standard event record",
54 * in `Z physics at LEP 1', eds. G. Altarelli, R. Kleiss and C. Verzegnassi,
55 * Geneva, Switzerland, September 4-5, 1989, CERN 89-08 (Geneva, 1989), Vol. 3, p. 327
56 * Disk representation is given by Fortran WRITE/READ format.
57 */
58template<typename momentum_type = double>
60{
61 int* nevhep; //!< Pointer to Event number
62 int* nhep; //!< Pointer to Number of entries in the event
63 int* isthep; //!< Pointer to Status code
64 int* idhep; //!< Pointer to PDG ID
65 int* jmohep; //!< Pointer to position of 1st and 2nd (or last!) mother
66 int* jdahep; //!< Pointer to position of 1nd and 2nd (or last!) daughter
67 momentum_type* phep; //!< Pointer to momentum: px, py, pz, e, m
68 momentum_type* vhep; //!< Pointer to time-space position: x, y, z, t
69};
70
71/** @brief comparison of two particles */
73{
74 /** @brief comparison of two particles */
75 bool operator()(ConstGenParticlePtr lx, ConstGenParticlePtr rx) const;
76};
77/** @brief Order vertices with equal paths. */
79{
80 /** @brief Order vertices with equal paths. If the paths are equal, order in other quantities.
81 * We cannot use id, as it can be assigned in different way*/
82 bool operator()(const std::pair<ConstGenVertexPtr, int>& lx, const std::pair<ConstGenVertexPtr, int>& rx) const;
83};
84/** @brief Calculates the path to the top (beam) particles */
85void calculate_longest_path_to_top(ConstGenVertexPtr v, std::map<ConstGenVertexPtr, int>& pathl);
86
87
88/** @brief Converts HEPEVT into GenEvent. */
89template <class T>
91{
92 if ( !evt ) { std::cerr << "HEPEVT_to_GenEvent_nonstatic - passed null event." << std::endl; return false;}
93 evt->set_event_number(A->event_number());
94 std::map<GenParticlePtr, int > hepevt_particles;
95 std::map<int, GenParticlePtr > particles_index;
96 std::map<GenVertexPtr, std::pair<std::set<int>, std::set<int> > > hepevt_vertices;
97 std::map<int, GenVertexPtr > vertex_index;
98 int ne=0;
99 ne=A->number_entries();
100 for ( int i = 1; i <= ne; i++ )
101 {
102 GenParticlePtr p = std::make_shared<GenParticle>();
103 p->set_momentum(FourVector(A->px(i), A->py(i), A->pz(i), A->e(i)));
104 p->set_status(A->status(i));
105 p->set_pid(A->id(i)); //Confusing!
106 p->set_generated_mass(A->m(i));
107 hepevt_particles[p] = i;
108 particles_index[i] = p;
109 GenVertexPtr v = std::make_shared<GenVertex>();
110 v->set_position(FourVector(A->x(i), A->y(i), A->z(i), A->t(i)));
111 v->add_particle_out(p);
112 std::set<int> in;
113 std::set<int> out;
114 out.insert(i);
115 vertex_index[i] = v;
116 hepevt_vertices[v] = std::pair<std::set<int>, std::set<int> >(in, out);
117 }
118 /* The part above is always correct as it is a raw information without any topology.*/
119
120 /* In this way we trust mother information. The "Trust daughters" is not implemented.*/
121 for (std::map<GenParticlePtr, int >::iterator it1 = hepevt_particles.begin(); it1 != hepevt_particles.end(); ++it1)
122 for (std::map<GenParticlePtr, int >::iterator it2 = hepevt_particles.begin(); it2 != hepevt_particles.end(); ++it2) {
123 if (A->first_parent(it2->second) <= it1->second && it1->second <= A->last_parent(it2->second)) hepevt_vertices[it2->first->production_vertex()].first.insert(it1->second);
124 }
125 /* Now all incoming sets are correct for all vertices. But we have duplicates.*/
126
127 /* Disconnect all particles from the vertices*/
128 for ( int i = 1; i <= A->number_entries(); i++ ) vertex_index[i]->remove_particle_out(particles_index[i]);
129
130 /*Fill container with vertices with unique sets of incoming particles. Merge the outcoming particle sets.*/
131 std::map<GenVertexPtr, std::pair<std::set<int>, std::set<int> > > final_vertices_map;
132 for (std::map<GenVertexPtr, std::pair<std::set<int>, std::set<int> > >::iterator vs = hepevt_vertices.begin(); vs != hepevt_vertices.end(); ++vs)
133 {
134 if ((final_vertices_map.size() == 0) || (vs->second.first.size() == 0 && vs->second.second.size() != 0)) { final_vertices_map.insert(*vs); continue; } /*Always insert particles out of nowhere*/
135 std::map<GenVertexPtr, std::pair<std::set<int>, std::set<int> > >::iterator v2;
136 for (v2 = final_vertices_map.begin(); v2 != final_vertices_map.end(); ++v2) if (vs->second.first == v2->second.first) {v2->second.second.insert(vs->second.second.begin(), vs->second.second.end()); break;}
137 if (v2 == final_vertices_map.end()) final_vertices_map.insert(*vs);
138 }
139
140 std::vector<GenParticlePtr> final_particles;
141 std::set<int> used;
142 for (std::map<GenVertexPtr, std::pair<std::set<int>, std::set<int> > >:: iterator it = final_vertices_map.begin(); it != final_vertices_map.end(); ++it)
143 {
144 GenVertexPtr v = it->first;
145 std::set<int> in = it->second.first;
146 std::set<int> out = it->second.second;
147 used.insert(in.begin(), in.end());
148 used.insert(out.begin(), out.end());
149 for (std::set<int>::iterator el = in.begin(); el != in.end(); ++el) v->add_particle_in(particles_index[*el]);
150 if (in.size() !=0 ) for (std::set<int>::iterator el = out.begin(); el != out.end(); ++el) v->add_particle_out(particles_index[*el]);
151 }
152 for (std::set<int>::iterator el = used.begin(); el != used.end(); ++el) final_particles.push_back(particles_index[*el]);
153 /* One can put here a check on the number of particles/vertices*/
154
155 evt->add_tree(final_particles);
156
157 return true;
158}
159/** @brief Converts GenEvent into HEPEVT. */
160template <class T>
162{
163 /// This writes an event out to the HEPEVT common block. The daughters
164 /// field is NOT filled, because it is possible to contruct graphs
165 /// for which the mothers and daughters cannot both be make sequential.
166 /// This is consistent with how pythia fills HEPEVT (daughters are not
167 /// necessarily filled properly) and how IO_HEPEVT reads HEPEVT.
168 if ( !evt ) return false;
169
170 /*AV Sorting the vertices by the lengths of their longest incoming paths assures the mothers will not go before the daughters*/
171 /* Calculate all paths*/
172 std::map<ConstGenVertexPtr, int> longest_paths;
173 for (ConstGenVertexPtr v: evt->vertices()) calculate_longest_path_to_top(v, longest_paths);
174 /* Sort paths*/
175 std::vector<std::pair<ConstGenVertexPtr, int> > sorted_paths;
176 std::copy(longest_paths.begin(), longest_paths.end(), std::back_inserter(sorted_paths));
177 std::sort(sorted_paths.begin(), sorted_paths.end(), pair_GenVertexPtr_int_greater());
178
179 std::vector<ConstGenParticlePtr> sorted_particles;
180 std::vector<ConstGenParticlePtr> stable_particles;
181 /*For a valid "Trust mothers" HEPEVT record we must keep mothers together*/
182 for (std::pair<ConstGenVertexPtr, int> it: sorted_paths)
183 {
184 std::vector<ConstGenParticlePtr> Q = it.first->particles_in();
185 std::sort(Q.begin(), Q.end(), GenParticlePtr_greater());
186 std::copy(Q.begin(), Q.end(), std::back_inserter(sorted_particles));
187 /*For each vertex put all outgoing particles w/o end vertex. Ordering of particles to produces reproduceable record*/
188 for (ConstGenParticlePtr pp: it.first->particles_out())
189 if (!(pp->end_vertex())) stable_particles.push_back(pp);
190 }
191 std::sort(stable_particles.begin(), stable_particles.end(), GenParticlePtr_greater());
192 std::copy(stable_particles.begin(), stable_particles.end(), std::back_inserter(sorted_particles));
193
194 int particle_counter;
195 particle_counter = std::min(int(sorted_particles.size()), A->max_number_entries());
196 /* fill the HEPEVT event record (MD code)*/
197 A->set_event_number(evt->event_number());
198 A->set_number_entries(particle_counter);
199 for ( int i = 1; i <= particle_counter; ++i )
200 {
201 A->set_status(i, sorted_particles[i-1]->status());
202 A->set_id(i, sorted_particles[i-1]->pid());
203 FourVector m = sorted_particles[i-1]->momentum();
204 A->set_momentum(i, m.px(), m.py(), m.pz(), m.e());
205 A->set_mass(i, sorted_particles[i-1]->generated_mass());
206 if ( sorted_particles[i-1]->production_vertex() &&
207 sorted_particles[i-1]->production_vertex()->particles_in().size())
208 {
209 FourVector p = sorted_particles[i-1]->production_vertex()->position();
210 A->set_position(i, p.x(), p.y(), p.z(), p.t() );
211 std::vector<int> mothers;
212 mothers.clear();
213
214 for (ConstGenParticlePtr it: sorted_particles[i-1]->production_vertex()->particles_in())
215 for ( int j = 1; j <= particle_counter; ++j )
216 if (sorted_particles[j-1] == (it))
217 mothers.push_back(j);
218 std::sort(mothers.begin(), mothers.end());
219 if (mothers.size() == 0)
220 mothers.push_back(0);
221 if (mothers.size() == 1) mothers.push_back(mothers[0]);
222
223 A->set_parents(i, mothers.front(), mothers.back());
224 }
225 else
226 {
227 A->set_position(i, 0, 0, 0, 0);
228 A->set_parents(i, 0, 0);
229 }
230 A->set_children(i, 0, 0);
231 }
232 return true;
233}
234
235
236/** @brief Converts HEPEVT into GenEvent. */
237template <class T>
239{
240 if ( !evt ) { std::cerr << "HEPEVT_to_GenEvent_static - passed null event." << std::endl; return false;}
241 evt->set_event_number(T::event_number());
242 std::map<GenParticlePtr, int > hepevt_particles;
243 std::map<int, GenParticlePtr > particles_index;
244 std::map<GenVertexPtr, std::pair<std::set<int>, std::set<int> > > hepevt_vertices;
245 std::map<int, GenVertexPtr > vertex_index;
246 int ne=0;
247 ne=T::number_entries();
248 for ( int i = 1; i <= ne; i++ )
249 {
250 GenParticlePtr p = std::make_shared<GenParticle>();
251 p->set_momentum(FourVector(T::px(i), T::py(i), T::pz(i), T::e(i)));
252 p->set_status(T::status(i));
253 p->set_pid(T::id(i)); //Confusing!
254 p->set_generated_mass(T::m(i));
255 hepevt_particles[p] = i;
256 particles_index[i] = p;
257 GenVertexPtr v = std::make_shared<GenVertex>();
258 v->set_position(FourVector(T::x(i), T::y(i), T::z(i), T::t(i)));
259 v->add_particle_out(p);
260 std::set<int> in;
261 std::set<int> out;
262 out.insert(i);
263 vertex_index[i] = v;
264 hepevt_vertices[v] = std::pair<std::set<int>, std::set<int> >(in, out);
265 }
266 /* The part above is always correct as it is a raw information without any topology.*/
267
268 /* In this way we trust mother information. The "Trust daughters" is not implemented.*/
269 for (std::map<GenParticlePtr, int >::iterator it1 = hepevt_particles.begin(); it1 != hepevt_particles.end(); ++it1)
270 for (std::map<GenParticlePtr, int >::iterator it2 = hepevt_particles.begin(); it2 != hepevt_particles.end(); ++it2) {
271 if (T::first_parent(it2->second) <= it1->second && it1->second <= T::last_parent(it2->second)) hepevt_vertices[it2->first->production_vertex()].first.insert(it1->second);
272 }
273 /* Now all incoming sets are correct for all vertices. But we have duplicates.*/
274
275 /* Disconnect all particles from the vertices*/
276 for ( int i = 1; i <= T::number_entries(); i++ ) vertex_index[i]->remove_particle_out(particles_index[i]);
277
278 /*Fill container with vertices with unique sets of incoming particles. Merge the outcoming particle sets.*/
279 std::map<GenVertexPtr, std::pair<std::set<int>, std::set<int> > > final_vertices_map;
280 for (std::map<GenVertexPtr, std::pair<std::set<int>, std::set<int> > >::iterator vs = hepevt_vertices.begin(); vs != hepevt_vertices.end(); ++vs)
281 {
282 if ((final_vertices_map.size() == 0) || (vs->second.first.size() == 0 && vs->second.second.size() != 0)) { final_vertices_map.insert(*vs); continue; } /*Always insert particles out of nowhere*/
283 std::map<GenVertexPtr, std::pair<std::set<int>, std::set<int> > >::iterator v2;
284 for (v2 = final_vertices_map.begin(); v2 != final_vertices_map.end(); ++v2) if (vs->second.first == v2->second.first) {v2->second.second.insert(vs->second.second.begin(), vs->second.second.end()); break;}
285 if (v2 == final_vertices_map.end()) final_vertices_map.insert(*vs);
286 }
287
288 std::vector<GenParticlePtr> final_particles;
289 std::set<int> used;
290 for (std::map<GenVertexPtr, std::pair<std::set<int>, std::set<int> > >:: iterator it = final_vertices_map.begin(); it != final_vertices_map.end(); ++it)
291 {
292 GenVertexPtr v = it->first;
293 std::set<int> in = it->second.first;
294 std::set<int> out = it->second.second;
295 used.insert(in.begin(), in.end());
296 used.insert(out.begin(), out.end());
297 for (std::set<int>::iterator el = in.begin(); el != in.end(); ++el) v->add_particle_in(particles_index[*el]);
298 if (in.size() !=0 ) for (std::set<int>::iterator el = out.begin(); el != out.end(); ++el) v->add_particle_out(particles_index[*el]);
299 }
300 for (std::set<int>::iterator el = used.begin(); el != used.end(); ++el) final_particles.push_back(particles_index[*el]);
301 /* One can put here a check on the number of particles/vertices*/
302
303 evt->add_tree(final_particles);
304
305 return true;
306}
307
308/** @brief Converts GenEvent into HEPEVT. */
309template <class T>
311{
312 /// This writes an event out to the HEPEVT common block. The daughters
313 /// field is NOT filled, because it is possible to contruct graphs
314 /// for which the mothers and daughters cannot both be make sequential.
315 /// This is consistent with how pythia fills HEPEVT (daughters are not
316 /// necessarily filled properly) and how IO_HEPEVT reads HEPEVT.
317 if ( !evt ) return false;
318
319 /*AV Sorting the vertices by the lengths of their longest incoming paths assures the mothers will not go before the daughters*/
320 /* Calculate all paths*/
321 std::map<ConstGenVertexPtr, int> longest_paths;
322 for (ConstGenVertexPtr v: evt->vertices()) calculate_longest_path_to_top(v, longest_paths);
323 /* Sort paths*/
324 std::vector<std::pair<ConstGenVertexPtr, int> > sorted_paths;
325 std::copy(longest_paths.begin(), longest_paths.end(), std::back_inserter(sorted_paths));
326 std::sort(sorted_paths.begin(), sorted_paths.end(), pair_GenVertexPtr_int_greater());
327
328 std::vector<ConstGenParticlePtr> sorted_particles;
329 std::vector<ConstGenParticlePtr> stable_particles;
330 /*For a valid "Trust mothers" HEPEVT record we must keep mothers together*/
331 for (std::pair<ConstGenVertexPtr, int> it: sorted_paths)
332 {
333 std::vector<ConstGenParticlePtr> Q = it.first->particles_in();
334 std::sort(Q.begin(), Q.end(), GenParticlePtr_greater());
335 std::copy(Q.begin(), Q.end(), std::back_inserter(sorted_particles));
336 /*For each vertex put all outgoing particles w/o end vertex. Ordering of particles to produces reproduceable record*/
337 for (ConstGenParticlePtr pp: it.first->particles_out())
338 if (!(pp->end_vertex())) stable_particles.push_back(pp);
339 }
340 std::sort(stable_particles.begin(), stable_particles.end(), GenParticlePtr_greater());
341 std::copy(stable_particles.begin(), stable_particles.end(), std::back_inserter(sorted_particles));
342
343 int particle_counter;
344 particle_counter = std::min(int(sorted_particles.size()), T::max_number_entries());
345 /* fill the HEPEVT event record (MD code)*/
346 T::set_event_number(evt->event_number());
347 T::set_number_entries(particle_counter);
348 for ( int i = 1; i <= particle_counter; ++i )
349 {
350 T::set_status(i, sorted_particles[i-1]->status());
351 T::set_id(i, sorted_particles[i-1]->pid());
352 FourVector m = sorted_particles[i-1]->momentum();
353 T::set_momentum(i, m.px(), m.py(), m.pz(), m.e());
354 T::set_mass(i, sorted_particles[i-1]->generated_mass());
355 if ( sorted_particles[i-1]->production_vertex() &&
356 sorted_particles[i-1]->production_vertex()->particles_in().size())
357 {
358 FourVector p = sorted_particles[i-1]->production_vertex()->position();
359 T::set_position(i, p.x(), p.y(), p.z(), p.t() );
360 std::vector<int> mothers;
361 mothers.clear();
362
363 for (ConstGenParticlePtr it: sorted_particles[i-1]->production_vertex()->particles_in())
364 for ( int j = 1; j <= particle_counter; ++j )
365 if (sorted_particles[j-1] == (it))
366 mothers.push_back(j);
367 std::sort(mothers.begin(), mothers.end());
368 if (mothers.size() == 0)
369 mothers.push_back(0);
370 if (mothers.size() == 1) mothers.push_back(mothers[0]);
371
372 T::set_parents(i, mothers.front(), mothers.back());
373 }
374 else
375 {
376 T::set_position(i, 0, 0, 0, 0);
377 T::set_parents(i, 0, 0);
378 }
379 T::set_children(i, 0, 0);
380 }
381 return true;
382}
383
384}
385#endif
Definition of class GenEvent.
Definition of class GenParticle.
Definition of class GenVertex.
Generic 4-vector.
Definition: FourVector.h:36
double e() const
Energy component of momentum.
Definition: FourVector.h:131
double pz() const
z-component of momentum
Definition: FourVector.h:124
double t() const
Time component of position/displacement.
Definition: FourVector.h:102
double px() const
x-component of momentum
Definition: FourVector.h:110
double py() const
y-component of momentum
Definition: FourVector.h:117
double x() const
x-component of position/displacement
Definition: FourVector.h:81
double y() const
y-component of position/displacement
Definition: FourVector.h:88
double z() const
z-component of position/displacement
Definition: FourVector.h:95
Stores event-related information.
Definition: GenEvent.h:41
void add_tree(const std::vector< GenParticlePtr > &particles)
Add whole tree in topological order.
Definition: GenEvent.cc:265
int event_number() const
Get event number.
Definition: GenEvent.h:148
void set_event_number(const int &num)
Set event number.
Definition: GenEvent.h:150
const std::vector< ConstGenVertexPtr > & vertices() const
Get list of vertices (const)
Definition: GenEvent.cc:43
HepMC3 main namespace.
bool HEPEVT_to_GenEvent_static(GenEvent *evt)
Converts HEPEVT into GenEvent.
bool HEPEVT_to_GenEvent_nonstatic(GenEvent *evt, T *A)
Converts HEPEVT into GenEvent.
void calculate_longest_path_to_top(ConstGenVertexPtr v, std::map< ConstGenVertexPtr, int > &pathl)
Calculates the path to the top (beam) particles.
bool GenEvent_to_HEPEVT_static(const GenEvent *evt)
Converts GenEvent into HEPEVT.
bool GenEvent_to_HEPEVT_nonstatic(const GenEvent *evt, T *A)
Converts GenEvent into HEPEVT.
comparison of two particles
bool operator()(ConstGenParticlePtr lx, ConstGenParticlePtr rx) const
comparison of two particles
C structure representing Fortran common block HEPEVT T. Sjöstrand et al., "A proposed standard event ...
int * jdahep
Pointer to position of 1nd and 2nd (or last!) daughter.
int * isthep
Pointer to Status code.
int * nevhep
Pointer to Event number.
int * idhep
Pointer to PDG ID.
momentum_type * vhep
Pointer to time-space position: x, y, z, t.
momentum_type * phep
Pointer to momentum: px, py, pz, e, m.
int * jmohep
Pointer to position of 1st and 2nd (or last!) mother.
int * nhep
Pointer to Number of entries in the event.
C structure representing Fortran common block HEPEVT T. Sjöstrand et al., "A proposed standard event ...
int jmohep[max_particles][2]
Position of 1st and 2nd (or last!) mother.
momentum_type vhep[max_particles][4]
Time-space position: x, y, z, t.
momentum_type phep[max_particles][5]
Momentum: px, py, pz, e, m.
int idhep[max_particles]
PDG ID.
int jdahep[max_particles][2]
Position of 1nd and 2nd (or last!) daughter.
int isthep[max_particles]
Status code.
int nevhep
Event number.
int nhep
Number of entries in the event.
Order vertices with equal paths.
bool operator()(const std::pair< ConstGenVertexPtr, int > &lx, const std::pair< ConstGenVertexPtr, int > &rx) const
Order vertices with equal paths. If the paths are equal, order in other quantities....