1 //********************************************************************
2 // Example of accessing the information stored in ESD friends
3 // Origin: Iouri Belikov, CERN, Jouri.Belikov@cern.ch
4 //********************************************************************
6 #if !defined( __CINT__) || defined(__MAKECINT__)
12 #include "AliESDfriend.h"
13 #include "AliTrackPointArray.h"
16 void ReadESDfriend(Bool_t readFriend=kTRUE) {
18 //Put here the names of the ESD files to be chained
21 Int_t n=sizeof(name)/sizeof(Char_t *);
22 TChain *esdTree=new TChain("esdTree");
23 for (Int_t i=0; i<n; i++) esdTree->AddFile(name[i]);
26 esdTree->SetBranchAddress("ESD",&ev);
28 // Attach the branch with ESD friends
31 esdTree->SetBranchStatus("ESDfriend*",1);
32 esdTree->SetBranchAddress("ESDfriend.",&evf);
35 Int_t nev=esdTree->GetEntries();
36 for (Int_t i=0; i<nev; i++) {
39 cout<<endl<<"Event number: "<<i<<endl;
40 Int_t n=ev->GetNumberOfTracks();
41 cout<<"Number of tracks: "<<n<<endl;
43 ev->SetESDfriend(evf); //Attach the friend to the ESD
45 // Now the attached information can be accessed via pointer to ESD.
46 // Example: indices of the TPC clusters associated with the track number 0.
48 const AliESDtrack *t=ev->GetTrack(0);
49 Int_t idx[AliESDfriendTrack::kMaxTPCcluster];
50 n=t->GetTPCclusters(idx);
51 cout<<"Track number 0"<<endl;
52 cout<<" Number of TPC clusters: "<<n<<endl;
53 cout<<" Index of the 7th TPC cluster: "<<idx[7]<<endl;
54 UChar_t map=t->GetITSClusterMap();
55 cout<<" ITS cluster map (from SPDs to SSDs): ";
56 for (Int_t i=0; i<6; i++) cout<<TESTBIT(map,i)<<' ';
59 // Example: track points associated with the track number 0.
60 const AliTrackPointArray *pa=t->GetTrackPointArray();
63 const Float_t *x=pa->GetX();
64 cout<<" Number of track points: "<<n<<endl;
66 cout<<" X coordinate of the 7th track point: "<<x[7]<<endl;