1 /**************************************************************************
2 * Copyright(c) 1998-2007, ALICE Experiment at CERN, All rights reserved. *
4 * Author: The ALICE Off-line Project. *
5 * Contributors are mentioned in the code where appropriate. *
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 **************************************************************************/
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 //-----------------------------------------------------------------------
25 Example for generation :
27 AliGenTHnSparse *gener = new AliGenTHnSparse();
28 gener->SetNumberParticles(10);
30 gener->SetThnSparse("file_name","thn_name");
36 #include "THnSparse.h"
38 #include "AliGenTHnSparse.h"
40 ClassImp(AliGenTHnSparse)
42 //_______________________________________________________________________
43 AliGenTHnSparse::AliGenTHnSparse():
49 // Default constructor
50 SetNumberParticles(1);
53 //_______________________________________________________________________
54 AliGenTHnSparse::AliGenTHnSparse(const AliGenTHnSparse& func):
61 SetNumberParticles(1);
64 //_______________________________________________________________________
65 AliGenTHnSparse & AliGenTHnSparse::operator=(const AliGenTHnSparse& func)
68 if(&func == this) return *this;
75 //_______________________________________________________________________
76 AliGenTHnSparse::~AliGenTHnSparse()
82 //_______________________________________________________________________
83 void AliGenTHnSparse::Generate()
86 // Generate Npart of id Ipart
88 Double_t rand[4]; // z, ptot, r, theta
89 Float_t pos[3], phi, ptot, theta, pt, z, r;
93 for (Int_t ipart = 0; ipart < fNpart; ipart++) {
101 // Phi: same for position and momemtum
103 phi=(-180+gRandom->Rndm()*360)*TMath::Pi()/180;
105 // position at production
107 pos[0] = r*TMath::Cos(phi);
108 pos[1] = r*TMath::Sin(phi);
111 // momentum at production
113 pt = ptot*TMath::Sin(theta);
114 mom[0] = pt*TMath::Cos(phi);
115 mom[1] = pt*TMath::Sin(phi);
116 mom[2] = ptot*TMath::Cos(theta);
120 Float_t polarization[3]= {0,0,0};
122 PushTrack(fTrackIt,-1,pdg,mom, pos, polarization,0,kPPrimary,nt);
128 //_______________________________________________________________________
129 void AliGenTHnSparse::Init()
132 // Initialisation, check consistency of selected file
133 printf("************ AliGenTHnSparse ****************\n");
134 printf("*********************************************\n");
136 AliFatal("THnSparse file not specified");
142 //_______________________________________________________________________
143 void AliGenTHnSparse::SetThnSparse(char *file_name, char *thn_name)
146 // Open the file and get object
147 fFile = new TFile(file_name);
148 fHn = (THnSparseF*)(fFile->Get(thn_name));