HepMC3 event record library
ReaderLHEF.cc
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1// -*- C++ -*-
2//
3// This file is part of HepMC
4// Copyright (C) 2014-2019 The HepMC collaboration (see AUTHORS for details)
5//
6/**
7 * @file ReaderLHEF.cc
8 * @brief Implementation of \b class ReaderLHEF
9 *
10 */
11#include "HepMC3/ReaderLHEF.h"
12namespace HepMC3
13{
14ReaderLHEF::ReaderLHEF(const std::string& filename)
15{
16 m_reader = new LHEF::Reader(filename);
17 init();
18}
19ReaderLHEF::ReaderLHEF(std::istream & stream)
20{
21 m_reader = new LHEF::Reader(stream);
22 init();
23}
24
25bool ReaderLHEF::skip(const int n)
26{
27 GenEvent evt;
28 for (int nn=n; nn>0; --nn)
29 {
30 if (!read_event(evt)) return false;
31 evt.clear();
32 }
33 return !failed();
34}
35
36
38{
39 m_neve=0;
40 m_failed=false;
41 // Create a HEPRUP attribute and initialize it from the reader.
42 m_hepr = std::make_shared<HEPRUPAttribute>();
43 m_hepr->heprup = m_reader->heprup;
44
45 // There may be some XML tags in the LHE file which are
46 // non-standard, but we can save them as well.
48
49 // Nowwe want to create a GenRunInfo object for the HepMC file, and
50 // we add the LHEF attribute to that.
51 set_run_info(std::make_shared<GenRunInfo>());
52 run_info()->add_attribute("HEPRUP", m_hepr);
53
54 // This is just a test to make sure we can add other attributes as
55 // well.
56 run_info()->add_attribute("NPRUP",
57 std::make_shared<FloatAttribute>(m_hepr->heprup.NPRUP));
58
59 // We want to be able to convey the different event weights to
60 // HepMC. In particular we need to add the names of the weights to
61 // the GenRunInfo object.
62 std::vector<std::string> weightnames;
63 weightnames.push_back("0"); // The first weight is always the
64 // default weight with name "0".
65 for ( int i = 0, N = m_hepr->heprup.weightinfo.size(); i < N; ++i )
66 weightnames.push_back(m_hepr->heprup.weightNameHepMC(i));
67 run_info()->set_weight_names(weightnames);
68
69 // We also want to convey the information about which generators was
70 // used.
71 for ( int i = 0, N = m_hepr->heprup.generators.size(); i < N; ++i )
72 {
74 tool.name = m_hepr->heprup.generators[i].name;
75 tool.version = m_hepr->heprup.generators[i].version;
76 tool.description = m_hepr->heprup.generators[i].contents;
77 run_info()->tools().push_back(tool);
78 }
79}
80/// @brief Destructor
82
84{
86 if (m_failed) return m_failed;
87 // To each GenEvent we want to add an attribute corresponding to
88 // the HEPEUP. Also here there may be additional non-standard
89 // information outside the LHEF <event> tags, which we may want to
90 // add.
91 std::shared_ptr<HEPEUPAttribute> hepe = std::make_shared<HEPEUPAttribute>();
92 if ( m_reader->outsideBlock.length() )
94 hepe->hepeup = m_reader->hepeup;
96 m_neve++;
97 // This is just a text to check that we can add additional
98 // attributes to each event.
99 ev.add_attribute("HEPEUP", hepe);
100 ev.add_attribute("AlphaQCD",
101 std::make_shared<DoubleAttribute>(hepe->hepeup.AQCDUP));
102 ev.add_attribute("AlphaEM",
103 std::make_shared<DoubleAttribute>(hepe->hepeup.AQEDUP));
104 ev.add_attribute("NUP",
105 std::make_shared<IntAttribute>(hepe->hepeup.NUP));
106 ev.add_attribute("IDPRUP",
107 std::make_shared<LongAttribute>(hepe->hepeup.IDPRUP));
108
109 // Now add the Particles from the LHE event to HepMC
110 GenParticlePtr p1 = std::make_shared<GenParticle>(hepe->momentum(0),
111 hepe->hepeup.IDUP[0],
112 hepe->hepeup.ISTUP[0]);
113 GenParticlePtr p2 = std::make_shared<GenParticle>(hepe->momentum(1),
114 hepe->hepeup.IDUP[1],
115 hepe->hepeup.ISTUP[1]);
116 GenVertexPtr vx = std::make_shared<GenVertex>();
117 vx->add_particle_in(p1);
118 vx->add_particle_in(p2);
119
120 for ( int i = 2; i < hepe->hepeup.NUP; ++i )
121 vx->add_particle_out(std::make_shared<GenParticle>
122 (hepe->momentum(i),
123 hepe->hepeup.IDUP[i],
124 hepe->hepeup.ISTUP[i]));
125 ev.add_vertex(vx);
126 // And we also want to add the weights.
127 std::vector<double> wts;
128 for ( int i = 0, N = hepe->hepeup.weights.size(); i < N; ++i )
129 wts.push_back(hepe->hepeup.weights[i].first);
130 ev.weights() = wts;
131 return m_failed;
132}
133/// @brief Return status of the stream
135
136/// @brief Close file stream
137void ReaderLHEF::close() { delete m_reader; };
138} // namespace HepMC3
139
140
Definition of class ReaderLHEF.
Stores event-related information.
Definition: GenEvent.h:41
void add_vertex(GenVertexPtr v)
Add vertex.
Definition: GenEvent.cc:97
void set_event_number(const int &num)
Set event number.
Definition: GenEvent.h:137
void add_attribute(const std::string &name, const std::shared_ptr< Attribute > &att, const int &id=0)
Add event attribute to event.
Definition: GenEvent.h:208
const std::vector< double > & weights() const
Get event weight values as a vector.
Definition: GenEvent.h:86
void clear()
Remove contents of this event.
Definition: GenEvent.cc:608
~ReaderLHEF()
Destructor.
Definition: ReaderLHEF.cc:81
void init()
Init helper.
Definition: ReaderLHEF.cc:37
bool failed() override
State.
Definition: ReaderLHEF.cc:134
LHEF::Reader * m_reader
The actual reader.
Definition: ReaderLHEF.h:57
bool read_event(GenEvent &ev) override
Reading event.
Definition: ReaderLHEF.cc:83
bool skip(const int) override
skip events
Definition: ReaderLHEF.cc:25
std::shared_ptr< HEPRUPAttribute > m_hepr
Holder of attributes.
Definition: ReaderLHEF.h:58
void close() override
Close.
Definition: ReaderLHEF.cc:137
bool m_failed
State of reader.
Definition: ReaderLHEF.h:60
ReaderLHEF(std::istream &)
The ctor to read from stream.
Definition: ReaderLHEF.cc:19
int m_neve
Event counter.
Definition: ReaderLHEF.h:59
std::shared_ptr< GenRunInfo > run_info() const
Get the global GenRunInfo object.
Definition: Reader.h:44
void set_run_info(std::shared_ptr< GenRunInfo > run)
Set the global GenRunInfo object.
Definition: Reader.h:64
std::string outsideBlock
Definition: LHEF.h:3002
HEPEUP hepeup
Definition: LHEF.h:3022
HEPRUP heprup
Definition: LHEF.h:3012
bool readEvent()
Definition: LHEF.h:2868
std::string headerBlock
Definition: LHEF.h:3007
std::string initComments
Definition: LHEF.h:3017
HepMC3 main namespace.
Interrnal struct for keeping track of tools.
Definition: GenRunInfo.h:38
std::string description
Other information about how the tool was used in the run.
Definition: GenRunInfo.h:48
std::string version
The version of the tool.
Definition: GenRunInfo.h:44
std::string name
The name of the tool.
Definition: GenRunInfo.h:41
static std::vector< XMLTag * > findXMLTags(std::string str, std::string *leftover=0)
Definition: LHEF.h:198