HepMC3 event record library: HepMC2_reader_example.cc Source File

HepMC3 event record library

HepMC2_reader_example.cc
1// -*- C++ -*-
2//
3// This file is part of HepMC
4// Copyright (C) 2014-2023 The HepMC collaboration (see AUTHORS for details)
5//
6/**
7 * @example HepMC2_reader_example.cc
8 * @brief Example of use of HepMC2 adapter
9 *
10 * Converts selected HepMC2 file to HepMC3 file
11 *
12 */
13#include "HepMC3/GenEvent.h"
14
15#include "HepMC3/ReaderAsciiHepMC2.h"
16#include "HepMC3/WriterAscii.h"
17#include "HepMC3/Print.h"
18
19#include <iostream>
20#include <cstdlib> // atoi
21using namespace HepMC3;
22
23/** Main program */
24int main(int argc, char **argv) {
25
26 if( argc < 3 ) {
27 std::cout<<"Usage: " << argv[0] <<" <input_hepmc2_file> <output_hepmc3_file> [<optional_events_limit>]" << std::endl;
28 exit(-1);
29 }
30
31 // Open input and output files
32 ReaderAsciiHepMC2 adapter(argv[1]);
33 WriterAscii output_file(argv[2]);
34 int events_parsed = 0;
35 int events_limit = 0;
36
37 if( argc >= 4 ) events_limit = atoi(argv[3]);
38
39 while( !adapter.failed() ) {
40 GenEvent evt(Units::GEV,Units::MM);
41
42 // Read event from input file
43 adapter.read_event(evt);
44
45 // If reading failed - exit loop
46 if( adapter.failed() ) break;
47
48 // Save event to output file
49 output_file.write_event(evt);
50
51 if(events_parsed==0) {
52 std::cout << " First event: " << std::endl;
53 Print::listing(evt);
54 }
55
56 ++events_parsed;
57 if( events_parsed%100 == 0 ) std::cout<<"Events parsed: "<<events_parsed<<std::endl;
58 if( events_limit && events_parsed >= events_limit ) break;
59 }
60
61 adapter.close();
62 output_file.close();
63
64 return 0;
65}
GenEvent.h
Definition of class GenEvent.
Print.h
Definition of static class Print.
ReaderAsciiHepMC2.h
Definition of class ReaderAsciiHepMC2.
WriterAscii.h
Definition of class WriterAscii.
HepMC3::GenEvent
Stores event-related information.
Definition GenEvent.h:47
HepMC3::Print::listing
static void listing(std::ostream &os, const GenEvent &event, unsigned short precision=2)
Print event in listing (HepMC2) format.
Definition Print.cc:52
HepMC3::ReaderAsciiHepMC2
Parser for HepMC2 I/O files.
Definition ReaderAsciiHepMC2.h:30
HepMC3::WriterAscii
GenEvent I/O serialization for structured text files.
Definition WriterAscii.h:25
HepMC3
HepMC3 main namespace.
Definition AnalysisExample.h:24