changes from Misha
[u/mrichter/AliRoot.git] / EVGEN / AliGenTHnSparse.cxx
CommitLineData
92a7e9c7 1/**************************************************************************
2 * Copyright(c) 1998-2007, ALICE Experiment at CERN, All rights reserved. *
3 * *
4 * Author: The ALICE Off-line Project. *
5 * Contributors are mentioned in the code where appropriate. *
6 * *
7 * Permission to use, copy, modify and distribute this software and its *
8 * documentation strictly for non-commercial purposes is hereby granted *
9 * without fee, provided that the above copyright notice appears in all *
10 * copies and that both the copyright notice and this permission notice *
11 * appear in the supporting documentation. The authors make no claims *
12 * about the suitability of this software for any purpose. It is *
13 * provided "as is" without express or implied warranty. *
14 **************************************************************************/
15
16//-----------------------------------------------------------------------
17// Particle generator according to 4 correlated variables : here
18// z, ptot, r, theta. The input is a THnSparse object included in
19// the root file (path and name to be set via the SetTHnSparse method).
20// This class is similar to AliGenFunction.
21//-----------------------------------------------------------------------
22// Author : X. Lopez - LPC Clermont (fr)
23//-----------------------------------------------------------------------
24/*
25 Example for generation :
92a7e9c7 26 AliGenTHnSparse *gener = new AliGenTHnSparse();
27 gener->SetNumberParticles(10);
fee5f683 28 gener->SetPart(13,kTRUE); // for generating id 13 and -13
92a7e9c7 29 gener->SetThnSparse("file_name","thn_name");
30 gener->Init();
31*/
32
33#include <TRandom.h>
34#include <TFile.h>
35#include "THnSparse.h"
36
37#include "AliGenTHnSparse.h"
38
fee5f683 39// NEW
40#include "AliRun.h"
4a33c50d 41#include "AliLog.h"
fee5f683 42#include "AliGenEventHeader.h"
43//
44
92a7e9c7 45ClassImp(AliGenTHnSparse)
46
47//_______________________________________________________________________
48AliGenTHnSparse::AliGenTHnSparse():
49 AliGenerator(),
50 fHn(0),
51 fFile(0),
fee5f683 52 fIpart(0),
53 fBoth(kFALSE)
92a7e9c7 54{
55 // Default constructor
56 SetNumberParticles(1);
57}
58
59//_______________________________________________________________________
60AliGenTHnSparse::AliGenTHnSparse(const AliGenTHnSparse& func):
61 AliGenerator(),
62 fHn(func.fHn),
63 fFile(func.fFile),
29e8465c 64 fIpart(func.fIpart),
65 fBoth(func.fBoth)
92a7e9c7 66{
67 // Copy constructor
68 SetNumberParticles(1);
69}
70
71//_______________________________________________________________________
72AliGenTHnSparse & AliGenTHnSparse::operator=(const AliGenTHnSparse& func)
73{
74 // Assigment operator
75 if(&func == this) return *this;
76 fHn = func.fHn;
77 fFile = func.fFile;
78 fIpart = func.fIpart;
29e8465c 79 fBoth = func.fBoth;
80
92a7e9c7 81 return *this;
82}
83
84//_______________________________________________________________________
85AliGenTHnSparse::~AliGenTHnSparse()
86{
87 // Destructor
88 delete fFile;
89}
90
91//_______________________________________________________________________
92void AliGenTHnSparse::Generate()
93{
92a7e9c7 94 // Generate Npart of id Ipart
4a33c50d 95 Int_t naccepted =0;
92a7e9c7 96
97 Double_t rand[4]; // z, ptot, r, theta
98 Float_t pos[3], phi, ptot, theta, pt, z, r;
99 Float_t mom[3];
100 Int_t pdg = fIpart;
101
fee5f683 102 for (Int_t ipart = 0; ipart < fNpart && naccepted<fNpart; ipart++) {
92a7e9c7 103
104 fHn->GetRandom(rand);
105 z=rand[0];
106 ptot=rand[1];
107 r=rand[2];
108 theta=rand[3];
109
110// Phi: same for position and momemtum
111
112 phi=(-180+gRandom->Rndm()*360)*TMath::Pi()/180;
113
114// position at production
115
116 pos[0] = r*TMath::Cos(phi);
117 pos[1] = r*TMath::Sin(phi);
118 pos[2] = z;
119
120// momentum at production
121
122 pt = ptot*TMath::Sin(theta);
123 mom[0] = pt*TMath::Cos(phi);
124 mom[1] = pt*TMath::Sin(phi);
125 mom[2] = ptot*TMath::Cos(theta);
126
127// propagation
128
fee5f683 129 Float_t polarization[3] = {0,0,0};
92a7e9c7 130 Int_t nt;
fee5f683 131
132// Part and anti-part
133
134 if(fBoth){
135 Double_t sign = gRandom->Rndm();
136 if(sign < 0.5) pdg = -fIpart;
137 else pdg = fIpart;
138 }
139
92a7e9c7 140 PushTrack(fTrackIt,-1,pdg,mom, pos, polarization,0,kPPrimary,nt);
fee5f683 141 naccepted++;
92a7e9c7 142 }
143
fee5f683 144 AliGenEventHeader* header = new AliGenEventHeader("THn");
145 gAlice->SetGenEventHeader(header);
92a7e9c7 146 return;
fee5f683 147
92a7e9c7 148}
149
150//_______________________________________________________________________
151void AliGenTHnSparse::Init()
152{
153
154 // Initialisation, check consistency of selected file
155 printf("************ AliGenTHnSparse ****************\n");
156 printf("*********************************************\n");
157 if (!fHn){
158 AliFatal("THnSparse file not specified");
159 }
160
161 return;
162}
163
164//_______________________________________________________________________
165void AliGenTHnSparse::SetThnSparse(char *file_name, char *thn_name)
166{
167
168 // Open the file and get object
224cb081 169 fFile = new TFile(file_name);
170 fHn = (THnSparseF*)(fFile->Get(thn_name));
92a7e9c7 171
172}