Fast vertexer: just a smearing of the true primary vertex position
[u/mrichter/AliRoot.git] / ITS / AliITSVertexerFast.cxx
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92e7a7bb 1/**************************************************************************
2 * Copyright(c) 1998-2003, 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#include <Riostream.h>
16#include <TArrayF.h>
17#include <TRandom.h>
18#include "AliITSVertex.h"
19#include <AliITSVertexerFast.h>
20#include "AliHeader.h"
21#include "AliGenEventHeader.h"
22#include "AliRun.h"
23#include "AliITSLoader.h"
24#include "AliRunLoader.h"
25
26/////////////////////////////////////////////////////////////////////////
27// //
28// Fast vertexer - True (i.e. generated) vertex coordinates //
29// are smeared with gaussians of given width //
30// Origin: masera@to.infn.it 25/09/2003 //
31// //
32/////////////////////////////////////////////////////////////////////////
33ClassImp(AliITSVertexerFast)
34
35
36
37//______________________________________________________________________
38AliITSVertexerFast::AliITSVertexerFast():AliITSVertexer() {
39 // Default Constructor
40 fSmear = 0;
41}
42
43//______________________________________________________________________
44AliITSVertexerFast::AliITSVertexerFast(Double_t *smear):AliITSVertexer() {
45 // Standard constructor
46 fSmear = new Double_t[3];
47 for(Int_t i=0;i<3;i++)fSmear[i]=smear[i];
48}
49
50//______________________________________________________________________
51AliITSVertexerFast::~AliITSVertexerFast(){
52 // Destructor
53 if(fSmear)delete [] fSmear;
54 fSmear = 0;
55}
56
57//______________________________________________________________________
58AliITSVertex* AliITSVertexerFast::FindVertexForCurrentEvent(Int_t evnumb){
59 // Defines the AliITSVertex for the current event
60 fCurrentVertex = 0;
61 AliRunLoader *rl =AliRunLoader::GetRunLoader();
62 rl->GetEvent(evnumb);
63 TArrayF primaryVertex(3); // true vertex
64 AliHeader* header = gAlice->GetHeader();
65 AliGenEventHeader* genEventHeader = header->GenEventHeader();
66 genEventHeader->PrimaryVertex(primaryVertex);
67
68 // Smearing
69 Double_t vrttrue[3],vrtx[3];
70 for(Int_t k=0; k<3;k++){
71 vrttrue[k] = static_cast<Double_t>(primaryVertex[k]);
72 vrtx[k] = gRandom->Gaus(vrttrue[k],fSmear[k]);
73 }
74 char name[30];
75 sprintf(name,"Vertex_%d",evnumb);
76 fCurrentVertex = new AliITSVertex(vrtx,fSmear,name);
77 fCurrentVertex->SetTruePos(vrttrue);
78 return fCurrentVertex;
79}
80
81//______________________________________________________________________
82void AliITSVertexerFast::FindVertices(){
83 // computes the vertices of the events in the range FirstEvent - LastEvent
84
85 AliRunLoader *rl = AliRunLoader::GetRunLoader();
86 AliITSLoader* iTSloader = (AliITSLoader*) rl->GetLoader("ITSLoader");
87 iTSloader->ReloadRecPoints();
88 for(Int_t i=fFirstEvent;i<=fLastEvent;i++){
89 rl->GetEvent(i);
90 FindVertexForCurrentEvent(i);
91 if(fCurrentVertex) WriteCurrentVertex();
92 else {
93 cout<<"Vertex not found for event "<<i<<endl;
94
95 }
96
97 }
98
99}
100
101//________________________________________________________
102void AliITSVertexerFast::PrintStatus() const {
103 // Print current status
104 cout <<"=======================================================\n";
105
106 cout<<"First event to be processed "<<fFirstEvent;
107 cout<<"\n Last event to be processed "<<fLastEvent<<endl;
108 cout<<"RMS for gaussian smearing: ";
109 for(Int_t k=0;k<3;k++)cout<<" "<<fSmear[k];
110 cout<<endl;
111}
112
113//______________________________________________________________________
114AliITSVertexerFast::AliITSVertexerFast(const AliITSVertexerFast &vtxr) :
115 AliITSVertexer(vtxr) {
116 // Copy constructor
117 // Copies are not allowed. The method is protected to avoid misuse.
118 Error("AliITSVertexerFast","Copy constructor not allowed\n");
119}
120
121//______________________________________________________________________
122AliITSVertexerFast& AliITSVertexerFast::operator=(const
123 AliITSVertexerFast& /* vtxr */){
124 // Assignment operator
125 // Assignment is not allowed. The method is protected to avoid misuse.
126 Error("= operator","Assignment operator not allowed\n");
127 return *this;
128}