Extacting the OCDB in a separate module. The detectors have write permission in the...
[u/mrichter/AliRoot.git] / TPC / AliTPCComparison.C
index 283ea93..e14f7ca 100644 (file)
@@ -3,7 +3,7 @@
  *                                                                          *
  *               Creates list of "trackable" tracks,                        *
  *             calculates efficiency, resolutions etc.                      *
- *  The ESD tracks must be in an appropriate state (kTPCin or kTPCrefit)    *
+ *     There is a possibility to run this macro over several events.         *
  *                                                                          *
  *           Origin: I.Belikov, CERN, Jouri.Belikov@cern.ch                 *
  * with several nice improvements by: M.Ivanov, GSI, m.ivanov@gsi.de        *
   #include <TH2F.h>
   #include <TTree.h>
   #include <TParticle.h>
-  #include <TPad.h>
   #include <TCanvas.h>
   #include <TLine.h>
   #include <TText.h>
   #include <TBenchmark.h>
   #include <TStyle.h>
-  #include <TKey.h>
+  #include <TFile.h>
+  #include <TROOT.h>
 
   #include "AliStack.h"
   #include "AliHeader.h"
   #include "AliTrackReference.h"
   #include "AliRunLoader.h"
-  #include "AliMagF.h"
   #include "AliRun.h"
-  #include "AliESD.h"
+  #include "AliESDEvent.h"
+  #include "AliESDtrack.h"
 
   #include "AliSimDigits.h"
   #include "AliTPC.h"
   #include "AliTPCParamSR.h"
   #include "AliTPCClustersArray.h"
   #include "AliTPCClustersRow.h"
-  #include "AliTPCtracker.h"
+  #include "AliTPCcluster.h"
   #include "AliTPCLoader.h"
-#endif
 
-struct GoodTrackTPC {
-  Int_t lab;
-  Int_t code;
-  Float_t px,py,pz;
-  Float_t x,y,z;
-};
+  #include "AliCDBManager.h"
+  #include "AliTPCcalibDB.h"
+#endif
 
-Int_t good_tracks_tpc(GoodTrackTPC *gt, const Int_t max, 
-const char* evfoldname=AliConfig::fgkDefaultEventFolderName);
+Int_t GoodTracksTPC(const Char_t *dir=".");
 
-extern AliRun *gAlice;
 extern TBenchmark *gBenchmark;
+extern TROOT *gROOT;
 
-Int_t AliTPCComparison() {
+static Int_t allgood=0;
+static Int_t allselected=0;
+static Int_t allfound=0;
+
+Int_t AliTPCComparison
+(Float_t ptcutl=0.2, Float_t ptcuth=10., const Char_t *dir=".") {
    gBenchmark->Start("AliTPCComparison");
 
    ::Info("AliTPCComparison.C","Doing comparison...");
 
-   if (gAlice) { 
-       delete gAlice->GetRunLoader();
-       delete gAlice;//if everything was OK here it is already NULL
-       gAlice = 0x0;
-    }
-
-   AliRunLoader *rl = AliRunLoader::Open("galice.root","COMPARISON");
-   if (!rl) {
-       ::Fatal("AliTPCComparison.C","Can't start session !");
-   }
 
-   rl->LoadgAlice();
-   if (rl->GetAliRun())
-   AliKalmanTrack::SetConvConst(
-     1000/0.299792458/rl->GetAliRun()->Field()->SolenoidField()
-   );
-   else {
-       ::Fatal("AliTPCComparison.C","Can't get AliRun !");
-   }
-   //rl->UnloadgAlice();
-  
 
-   /* Generate a list of "good" tracks */
-   const Int_t MAX=20000;
-   GoodTrackTPC gt[MAX];
-   Int_t ngood=0;
-   ifstream in("good_tracks_tpc");
-   if (in) {
-      ::Info("AliTPCComparison.C","Reading good tracks...");
-      while (in>>gt[ngood].lab>>gt[ngood].code>>
-                 gt[ngood].px>>gt[ngood].py>>gt[ngood].pz>>
-                 gt[ngood].x >>gt[ngood].y >>gt[ngood].z) {
-         ngood++;
-         if (ngood==MAX) {
-           ::Warning("AliTPCComparison.C","Too many good tracks !");
-           break;
-         }     
-      }
-      if (!in.eof()) 
-        ::Fatal("AliTPCComparison.C","Read error (good_tracks_tpc) !");
-   } else {
-      ::Info
-      ("AliTPCComparison","Marking good tracks (this will take a while)...");
-      ngood=good_tracks_tpc(gt,MAX,"COMPARISON");
-      ofstream out("good_tracks_tpc");
-      if (out) {
-         for (Int_t ngd=0; ngd<ngood; ngd++)            
-           out<<gt[ngd].lab<<' '<<gt[ngd].code<<' '<<
-                 gt[ngd].px<<' '<<gt[ngd].py<<' '<<gt[ngd].pz<<' '<<
-                 gt[ngd].x <<' '<<gt[ngd].y <<' '<<gt[ngd].z <<endl;
-      } else 
-         ::Fatal("AliTPCComparison.C","Can not open file (good_tracks_tpc) !");
-      out.close();
-   }
+   TH1F *hp=(TH1F*)gROOT->FindObject("hp");
+   if (!hp) hp=new TH1F("hp","PHI resolution",50,-20.,20.); 
+   hp->SetFillColor(4);
 
-   Int_t i=0; TObjArray tarray(MAX);
-   { /*Load tracks*/
-   TFile *ef=TFile::Open("AliESDtpc.root");
-   if ((!ef)||(!ef->IsOpen())) {
-      ::Fatal("AliTPCComparison.C","Can't open AliESDtpc.root !");
-   }
-   TKey *key=0;
-   TIter next(ef->GetListOfKeys());
-   if ((key=(TKey*)next())!=0) {
-     AliESD *event=(AliESD*)key->ReadObj();
-     Int_t ntrk=event->GetNumberOfTracks();
-     for (Int_t i=0; i<ntrk; i++) {
-        AliESDtrack *t=event->GetTrack(i);
-        if ((t->GetStatus()&AliESDtrack::kTPCin)==0) continue;
-        AliTPCtrack *iotrack=new AliTPCtrack(*t);
-        tarray.AddLast(iotrack);
-     }
-     delete event;
-   }
-   ef->Close();
-   }
-   Int_t nentr=tarray.GetEntriesFast();
+   TH1F *hl=(TH1F*)gROOT->FindObject("hl");
+   if (!hl) hl=new TH1F("hl","LAMBDA resolution",50,-20,20);
+   hl->SetFillColor(4);
 
-   TH1F *hp=new TH1F("hp","PHI resolution",50,-20.,20.); hp->SetFillColor(4);
-   TH1F *hl=new TH1F("hl","LAMBDA resolution",50,-20,20);hl->SetFillColor(4);
-   TH1F *hpt=new TH1F("hpt","Relative Pt resolution",30,-10.,10.); 
-   hpt->SetFillColor(2); 
-   TH1F *hmpt=new TH1F("hmpt","Relative Pt resolution (pt>4GeV/c)",30,-60,60); 
+   TH1F *hpt=(TH1F*)gROOT->FindObject("hpt");
+   if (!hpt) hpt=new TH1F("hpt","Relative Pt resolution",30,-10.,10.); 
+   hpt->SetFillColor(2);
+   TH1F *hmpt=(TH1F*)gROOT->FindObject("hmpt");
+   if (!hmpt) 
+      hmpt=new TH1F("hmpt","Relative Pt resolution (pt>4GeV/c)",30,-60,60); 
    hmpt->SetFillColor(6);
 
-   TH1F *hgood=new TH1F("hgood","Good tracks",30,0.2,6.1);    
-   TH1F *hfound=new TH1F("hfound","Found tracks",30,0.2,6.1);
-   TH1F *hfake=new TH1F("hfake","Fake tracks",30,0.2,6.1);
-   TH1F *hg=new TH1F("hg","Efficiency for good tracks",30,0.2,6.1);
+
+
+   TH1F *hgood=(TH1F*)gROOT->FindObject("hgood");
+   if (!hgood) hgood=new TH1F("hgood","Good tracks",30,0.2,6.1);
+    
+   TH1F *hfound=(TH1F*)gROOT->FindObject("hfound");
+   if (!hfound) hfound=new TH1F("hfound","Found tracks",30,0.2,6.1);
+
+   TH1F *hfake=(TH1F*)gROOT->FindObject("hfake");
+   if (!hfake) hfake=new TH1F("hfake","Fake tracks",30,0.2,6.1);
+
+   TH1F *hg=(TH1F*)gROOT->FindObject("hg");
+   if (!hg) hg=new TH1F("hg","Efficiency for good tracks",30,0.2,6.1);
    hg->SetLineColor(4); hg->SetLineWidth(2);
-   TH1F *hf=new TH1F("hf","Efficiency for fake tracks",30,0.2,6.1);
+
+   TH1F *hf=(TH1F*)gROOT->FindObject("hf");
+   if (!hf) hf=new TH1F("hf","Efficiency for fake tracks",30,0.2,6.1);
    hf->SetFillColor(1); hf->SetFillStyle(3013); hf->SetLineWidth(2);
 
-   TH1F *he =new TH1F("he","dE/dX for pions with 0.4<p<0.5 GeV/c",50,0.,100.);
-   TH2F *hep=new TH2F("hep","dE/dX vs momentum",50,0.,2.,50,0.,400.);
+   TH1F *he=(TH1F*)gROOT->FindObject("he");
+   if (!he) 
+      he =new TH1F("he","dE/dX for pions with 0.4<p<0.5 GeV/c",50,0.,100.);
+
+   TH2F *hep=(TH2F*)gROOT->FindObject("hep");
+   if (!hep) hep=new TH2F("hep","dE/dX vs momentum",50,0.,2.,50,0.,400.);
    hep->SetMarkerStyle(8);
    hep->SetMarkerSize(0.4);
 
-   //MI change
-   Int_t mingood=ngood;
-   Int_t track_notfound[MAX], itrack_notfound=0;
-   Int_t track_fake[MAX], itrack_fake=0;
-   Int_t track_multifound[MAX], track_multifound_n[MAX], itrack_multifound=0;
 
-   while (ngood--) {
-      Int_t lab=gt[ngood].lab,tlab=-1;
-      Float_t ptg=
-      TMath::Sqrt(gt[ngood].px*gt[ngood].px + gt[ngood].py*gt[ngood].py);
+   Char_t fname[100];
+   sprintf(fname,"%s/GoodTracksTPC.root",dir);
 
-      if (ptg<1e-33) continue; // for those not crossing 0 pad row
+   TFile *refFile=TFile::Open(fname,"old");
+   if (!refFile || !refFile->IsOpen()) {
+     ::Info("AliTPCComparison.C","Marking good tracks (will take a while)...");
+     if (GoodTracksTPC(dir)) {
+        ::Error("AliTPCComparison.C","Can't generate the reference file !");
+        return 1;
+     }
+   }
+   refFile=TFile::Open(fname,"old");
+   if (!refFile || !refFile->IsOpen()) {
+     ::Error("AliTPCComparison.C","Can't open the reference file !");
+     return 2;
+   }   
+  
+   TTree *tpcTree=(TTree*)refFile->Get("tpcTree");
+   if (!tpcTree) {
+     ::Error("AliTPCComparison.C","Can't get the reference tree !");
+     return 3;
+   }
+   TBranch *branch=tpcTree->GetBranch("TPC");
+   if (!branch) {
+     ::Error("AliTPCComparison.C","Can't get the TPC branch !");
+     return 4;
+   }
+   TClonesArray dummy("AliTrackReference",1000), *refs=&dummy;
+   branch->SetAddress(&refs);
 
-      hgood->Fill(ptg);
 
-      AliTPCtrack *track=0;
-      for (i=0; i<nentr; i++) {
-          track=(AliTPCtrack*)tarray.UncheckedAt(i);
-          tlab=track->GetLabel();
-          if (lab==TMath::Abs(tlab)) break;
-      }
-      if (i==nentr) {
-       track_notfound[itrack_notfound++]=lab;
-        continue;
-      }
-      
-      //MI change  - addition
-      Int_t micount=0;
-      Int_t mi;
-      AliTPCtrack * mitrack;
-      for (mi=0; mi<nentr; mi++) {
-       mitrack=(AliTPCtrack*)tarray.UncheckedAt(mi);          
-       if (lab==TMath::Abs(mitrack->GetLabel())) micount++;
-      }
-      if (micount>1) {
-       track_multifound[itrack_multifound]=lab;
-       track_multifound_n[itrack_multifound]=micount;
-       itrack_multifound++;
+   sprintf(fname,"%s/AliESDs.root",dir);
+   TFile *ef=TFile::Open(fname);
+   if ((!ef)||(!ef->IsOpen())) {
+      sprintf(fname,"%s/AliESDtpc.root",dir);
+      ef=TFile::Open(fname);
+      if ((!ef)||(!ef->IsOpen())) {
+         ::Error("AliTPCComparison.C","Can't open AliESDtpc.root !");
+         return 5;
       }
-      
-      Double_t xk=gt[ngood].x;
-      track->PropagateTo(xk);
+   }
+   AliESDEvent* event = new AliESDEvent();
+   TTree* esdTree = (TTree*) ef->Get("esdTree");
+   if (!esdTree) {
+      ::Error("AliTPCComparison.C", "no ESD tree found");
+      return 6;
+   }
+   event->ReadFromTree(esdTree);
+
+
+   //******* Loop over events *********
+   Int_t e=0;
+   while (esdTree->GetEvent(e)) {
+      cout<<endl<<endl<<"********* Processing event number: "<<e<<"*******\n";
 
-      if (lab==tlab) hfound->Fill(ptg);
-      else { 
-       track_fake[itrack_fake++]=lab;
-       hfake->Fill(ptg); 
+      Int_t nentr=event->GetNumberOfTracks();
+      allfound+=nentr;
+
+      if (tpcTree->GetEvent(e++)==0) {
+        cerr<<"No reconstructable tracks !\n";
+         continue;
       }
 
-      Double_t par[5]; track->GetExternalParameters(xk,par);
-      Float_t phi=TMath::ASin(par[2]) + track->GetAlpha();
-      if (phi<-TMath::Pi()) phi+=2*TMath::Pi();
-      if (phi>=TMath::Pi()) phi-=2*TMath::Pi();
-      Float_t lam=TMath::ATan(par[3]); 
-      Float_t pt_1=TMath::Abs(par[4]);
+      Int_t ngood=refs->GetEntriesFast(); 
+      allgood+=ngood;
+
+      const Int_t MAX=15000;
+    //MI change
+      Int_t track_notfound[MAX], itrack_notfound=0;
+      Int_t track_fake[MAX], itrack_fake=0;
+      Int_t track_multifound[MAX],track_multifound_n[MAX],itrack_multifound=0;
+
+      Int_t i;
+      for (Int_t k=0; k<ngood; k++) {
+       AliTrackReference *ref=(AliTrackReference*)refs->UncheckedAt(k); 
+        Int_t lab=ref->Label(), tlab=-1;
+        Float_t ptg=TMath::Sqrt(ref->Px()*ref->Px() + ref->Py()*ref->Py());
+
+        if (ptg<1e-33) continue; // for those not crossing 0 pad row
+  
+        if (ptg<ptcutl) continue;
+        if (ptg>ptcuth) continue;
+
+        allselected++;
 
-      if (TMath::Abs(gt[ngood].code)==11 && ptg>4.) {
-         hmpt->Fill((pt_1 - 1/ptg)/(1/ptg)*100.);
-      } else {
-         Float_t phig=TMath::ATan2(gt[ngood].py,gt[ngood].px);
-         hp->Fill((phi - phig)*1000.);
+        hgood->Fill(ptg);
 
-         Float_t lamg=TMath::ATan2(gt[ngood].pz,ptg);
-         hl->Fill((lam - lamg)*1000.);
+        AliESDtrack *track=0;
+        for (i=0; i<nentr; i++) {
+          track=event->GetTrack(i);
+          tlab=track->GetTPCLabel();
+          if (lab==TMath::Abs(tlab)) break;
+        }
+        if (i==nentr) {
+          track_notfound[itrack_notfound++]=lab;
+           continue;
+        }
+      
+        //MI change  - addition
+        Int_t micount=0;
+        Int_t mi;
+        AliESDtrack * mitrack;
+        for (mi=0; mi<nentr; mi++) {
+         mitrack=event->GetTrack(mi);          
+         if (lab==TMath::Abs(mitrack->GetTPCLabel())) micount++;
+        }
+        if (micount>1) {
+         track_multifound[itrack_multifound]=lab;
+         track_multifound_n[itrack_multifound]=micount;
+         itrack_multifound++;
+        }
+        if ((track->GetStatus()&AliESDtrack::kTPCrefit)==0) continue;
+        if (lab==tlab) hfound->Fill(ptg);
+        else { 
+         track_fake[itrack_fake++]=lab;
+         hfake->Fill(ptg); 
+        }
+      
+        Double_t pxpypz[3]; track->GetInnerPxPyPz(pxpypz);
+        Float_t phi=TMath::ATan2(pxpypz[1],pxpypz[0]);
+        if (phi<-TMath::Pi()) phi+=2*TMath::Pi();
+        if (phi>=TMath::Pi()) phi-=2*TMath::Pi();
+        Double_t pt=TMath::Sqrt(pxpypz[0]*pxpypz[0]+pxpypz[1]*pxpypz[1]);
+        Float_t lam=TMath::ATan2(pxpypz[2],pt); 
+        Float_t pt_1=1/pt;
+
+        Int_t pdg=(Int_t)ref->GetLength();  //this is particle's PDG !
+
+        if (TMath::Abs(pdg)==11 && ptg>4.) {//high momentum electrons
+           hmpt->Fill((pt_1 - 1/ptg)/(1/ptg)*100.);
+        } else {
+           Float_t phig=TMath::ATan2(ref->Py(),ref->Px());
+           hp->Fill((phi - phig)*1000.);
+
+           Float_t lamg=TMath::ATan2(ref->Pz(),ptg);
+           hl->Fill((lam - lamg)*1000.);
+
+           hpt->Fill((pt_1 - 1/ptg)/(1/ptg)*100.);
+        }
 
-         hpt->Fill((pt_1 - 1/ptg)/(1/ptg)*100.);
+        Float_t mom=pt/TMath::Cos(lam);
+        Float_t dedx=track->GetTPCsignal();
+        hep->Fill(mom,dedx,1.);
+        if (TMath::Abs(pdg)==211) //pions
+          if (mom>0.4 && mom<0.5) {
+              he->Fill(dedx,1.);
+           }
       }
 
-      Float_t mom=1./(pt_1*TMath::Cos(lam));
-      Float_t dedx=track->GetdEdx();
-      hep->Fill(mom,dedx,1.);
-      if (TMath::Abs(gt[ngood].code)==211)
-        if (mom>0.4 && mom<0.5) {
-            he->Fill(dedx,1.);
-         }
+      cout<<"\nList of Not found tracks :\n";
+      for ( i = 0; i< itrack_notfound; i++){
+        cout<<track_notfound[i]<<"\t";
+        if ((i%5)==4) cout<<"\n";
+      }
+      cout<<"\nList of fake  tracks :\n";
+      for ( i = 0; i< itrack_fake; i++){
+        cout<<track_fake[i]<<"\t";
+        if ((i%5)==4) cout<<"\n";
+      }
+      cout<<"\nList of multiple found tracks :\n";
+      for ( i=0; i<itrack_multifound; i++) {
+          cout<<"id.   "<<track_multifound[i]
+              <<"     found - "<<track_multifound_n[i]<<"times\n";
+      }
 
-   }
+      cout<<"Number of found tracks ="<<nentr<<endl;
+      cout<<"Number of \"good\" tracks ="<<ngood<<endl;
 
-   cout<<"\nList of Not found tracks :\n";
-   for ( i = 0; i< itrack_notfound; i++){
-     cout<<track_notfound[i]<<"\t";
-     if ((i%5)==4) cout<<"\n";
-   }
-   cout<<"\nList of fake  tracks :\n";
-   for ( i = 0; i< itrack_fake; i++){
-     cout<<track_fake[i]<<"\t";
-     if ((i%5)==4) cout<<"\n";
-   }
-    cout<<"\nList of multiple found tracks :\n";
-   for ( i=0; i<itrack_multifound; i++) {
-       cout<<"id.   "<<track_multifound[i]
-           <<"     found - "<<track_multifound_n[i]<<"times\n";
-   }
+      refs->Clear();
+  }// ***** End of the loop over events
 
-   Stat_t ng=hgood->GetEntries(), nf=hfound->GetEntries();
-   if (ng!=0) cerr<<"\n\nIntegral efficiency is about "<<nf/ng*100.<<" %\n";
-   cout<<"Total number of found tracks ="<<nentr<<endl;
-   cout<<"Total number of \"good\" tracks ="
-       <<mingood<<"   (selected for comparison: "<<ng<<')'<<endl<<endl;
+   delete event;
+   delete esdTree;
+   ef->Close();
+
+   delete tpcTree;
+   refFile->Close();
 
+   Stat_t ng=hgood->GetEntries(), nf=hfound->GetEntries();
+   if (ng!=0) cout<<"\n\nIntegral efficiency is about "<<nf/ng*100.<<" %\n";
+   cout<<"Total number selected of \"good\" tracks ="<<allselected<<endl<<endl;
+   cout<<"Total number of found tracks ="<<allfound<<endl;
+   cout<<"Total number of \"good\" tracks ="<<allgood<<endl;
+   cout<<endl;
 
    gStyle->SetOptStat(111110);
    gStyle->SetOptFit(1);
 
    TCanvas *c1=new TCanvas("c1","",0,0,700,850);
 
+   Int_t minc=33; 
+
    TPad *p1=new TPad("p1","",0,0.3,.5,.6); p1->Draw();
    p1->cd(); p1->SetFillColor(42); p1->SetFrameFillColor(10); 
-   hp->SetFillColor(4);  hp->SetXTitle("(mrad)"); hp->Fit("gaus"); c1->cd();
+   hp->SetFillColor(4);  hp->SetXTitle("(mrad)"); 
+   if (hp->GetEntries()<minc) hp->Draw(); else hp->Fit("gaus"); c1->cd();
 
    TPad *p2=new TPad("p2","",0.5,.3,1,.6); p2->Draw(); 
    p2->cd(); p2->SetFillColor(42); p2->SetFrameFillColor(10);
-   hl->SetXTitle("(mrad)"); hl->Fit("gaus"); c1->cd();
+   hl->SetXTitle("(mrad)");
+   if (hl->GetEntries()<minc) hl->Draw(); else hl->Fit("gaus"); c1->cd();
 
    TPad *p3=new TPad("p3","",0,0,0.5,0.3); p3->Draw();
    p3->cd(); p3->SetFillColor(42); p3->SetFrameFillColor(10); 
-   hpt->SetXTitle("(%)"); hpt->Fit("gaus"); c1->cd();
+   hpt->SetXTitle("(%)");
+   if (hpt->GetEntries()<minc) hpt->Draw(); else hpt->Fit("gaus"); c1->cd();
 
    TPad *p4=new TPad("p4","",0.5,0,1,0.3); p4->Draw();
    p4->cd(); p4->SetFillColor(42); p4->SetFrameFillColor(10);
-   hmpt->SetXTitle("(%)"); hmpt->Fit("gaus"); c1->cd();
+   hmpt->SetXTitle("(%)");
+   if (hmpt->GetEntries()<minc) hmpt->Draw(); else hmpt->Fit("gaus"); c1->cd();
 
    TPad *p5=new TPad("p5","",0,0.6,1,1); p5->Draw(); p5->cd(); 
    p5->SetFillColor(41); p5->SetFrameFillColor(10);
@@ -315,53 +355,69 @@ Int_t AliTPCComparison() {
    p6->cd(); p6->SetFillColor(42); p6->SetFrameFillColor(10); 
    he->SetFillColor(2); he->SetFillStyle(3005);  
    he->SetXTitle("Arbitrary Units"); 
-   he->Fit("gaus"); c2->cd();
+   if (he->GetEntries()<minc) he->Draw(); else he->Fit("gaus"); c2->cd();
 
    TPad *p7=new TPad("p7","",0.,0.5,1.,1.); p7->Draw(); 
    p7->cd(); p7->SetFillColor(42); p7->SetFrameFillColor(10);
    hep->SetXTitle("p (Gev/c)"); hep->SetYTitle("dE/dX (Arb. Units)"); 
    hep->Draw(); c1->cd();
 
+   TFile fc("AliTPCComparison.root","RECREATE");
+   c1->Write();
+   c2->Write();
+   fc.Close();
+
    gBenchmark->Stop("AliTPCComparison");
    gBenchmark->Show("AliTPCComparison");
 
-   delete rl;
    return 0;
 }
 
 
-Int_t 
-good_tracks_tpc(GoodTrackTPC *gt, const Int_t max, const char* evfoldname) {
-   Int_t nt=0;
+Int_t GoodTracksTPC(const Char_t *dir) {
+   Char_t fname[100];
+   sprintf(fname,"%s/galice.root",dir);
 
-   AliRunLoader *rl = AliRunLoader::GetRunLoader(evfoldname);
-   if (rl == 0x0) {
-      ::Fatal("AliTPCComparison.C::good_tracks_tpc",
-              "Can not find Run Loader in Folder Named %s",
-              evfoldname);
+   AliRunLoader *rl = AliRunLoader::Open(fname,"COMPARISON");
+   if (!rl) {
+      ::Error("GoodTracksTPC","Can't start session !");
+      return 1;
    }
+
+   rl->LoadgAlice();
+   rl->LoadHeader();
+   rl->LoadKinematics();
+   rl->LoadTrackRefs();
+
    AliTPCLoader *tpcl = (AliTPCLoader *)rl->GetLoader("TPCLoader");
    if (tpcl == 0x0) {
-       ::Fatal("AliTPCHits2Digits.C","Can not find TPCLoader !");
+      ::Error("GoodTracksTPC","Can not find TPCLoader !");
+      delete rl;
+      return 2;
    }
-   
-   rl->LoadgAlice();
-   
+      
    AliTPC *TPC=(AliTPC*)rl->GetAliRun()->GetDetector("TPC");
    Int_t ver = TPC->IsVersion(); 
-   cerr<<"TPC version "<<ver<<" has been found !\n";
+   cout<<"TPC version "<<ver<<" has been found !\n";
+   if (ver==1) tpcl->LoadRecPoints();
+   else if (ver==2) tpcl->LoadDigits();
+   else {
+      ::Error("GoodTracksTPC","Wrong TPC version !");
+      delete rl;
+      return 3;
+   } 
 
-   rl->CdGAFile();
-   AliTPCParamSR *digp=(AliTPCParamSR*)gDirectory->Get("75x40_100x60_150x60");
+
+   AliCDBManager *man=AliCDBManager::Instance();
+   man->SetDefaultStorage("local://$ALICE_ROOT/OCDB");
+   man->SetRun(0);
+   AliTPCParamSR *digp=
+   (AliTPCParamSR*)(AliTPCcalibDB::Instance()->GetParameters());
    if (!digp) { 
-     ::Fatal("AliTPCHits2Digits.C","TPC parameters have not been found !"); 
+     ::Error("AliTPCComparison.C","TPC parameters have not been found !");
+     delete rl;
+     return 4; 
    }
-   TPC->SetParam(digp);
-
-   rl->LoadHeader();
-
-   Int_t np = rl->GetHeader()->GetNtrack();
-      
 
    Int_t nrow_up=digp->GetNRowUp();
    Int_t nrows=digp->GetNRowLow()+nrow_up;
@@ -369,21 +425,40 @@ good_tracks_tpc(GoodTrackTPC *gt, const Int_t max, const char* evfoldname) {
    Int_t gap=Int_t(0.125*nrows), shift=Int_t(0.5*gap);
    Int_t good_number=Int_t(0.4*nrows);
 
-   Int_t *good=new Int_t[np];
-   Int_t i;
-   for (i=0; i<np; i++) good[i]=0;
-
-
-   switch (ver) {
-   case 1:
-     {
-      tpcl->LoadRecPoints();      
-      AliTPCClustersArray *pca=new AliTPCClustersArray, &ca=*pca;
-      ca.Setup(digp);
-      ca.SetClusterType("AliTPCcluster");
-      ca.ConnectTree(tpcl->TreeR());
-      Int_t nrows=Int_t(ca.GetTree()->GetEntries());
-      for (Int_t n=0; n<nrows; n++) {
+   Int_t nev=rl->GetNumberOfEvents();
+   ::Info("GoodTracksTPC","Number of events : %d\n",nev);  
+
+
+   sprintf(fname,"%s/GoodTracksTPC.root",dir);
+   TFile *file=TFile::Open(fname,"recreate");
+
+   TClonesArray dummy("AliTrackReference",1000), *refs=&dummy;
+   TTree tpcTree("tpcTree","Tree with info about the reconstructable TPC tracks");
+   tpcTree.Branch("TPC",&refs);
+
+   //********  Loop over generated events 
+   for (Int_t e=0; e<nev; e++) {
+     Int_t nt=0;
+     refs->Clear();
+
+     Int_t i;
+
+     rl->GetEvent(e);  file->cd();
+
+     Int_t np = rl->GetHeader()->GetNtrack();
+     cout<<"Event "<<e<<" Number of particles: "<<np<<endl;
+
+     //******** Fill the "good" masks
+     Int_t *good=new Int_t[np]; for (i=0; i<np; i++) good[i]=0;
+     switch (ver) {
+     case 1:
+        {
+        AliTPCClustersArray *pca=new AliTPCClustersArray, &ca=*pca;
+        ca.Setup(digp);
+        ca.SetClusterType("AliTPCcluster");
+        ca.ConnectTree(tpcl->TreeR());
+        Int_t nrows=Int_t(ca.GetTree()->GetEntries());
+        for (Int_t n=0; n<nrows; n++) {
           AliSegmentID *s=ca.LoadEntry(n);
           Int_t sec,row;
           digp->AdjustSectorRow(s->GetID(),sec,row);
@@ -408,29 +483,27 @@ good_tracks_tpc(GoodTrackTPC *gt, const Int_t max, const char* evfoldname) {
               good[lab]++;
           }
           ca.ClearRow(sec,row);
-      }
-      delete pca;
-      tpcl->UnloadRecPoints();
-     }
-     break;
-   case 2:
-     {
-      tpcl->LoadDigits();
-      TTree *TD=tpcl->TreeD();
+        }
+        delete pca;
+        }
+        break;
+     case 2:
+        {
+        TTree *TD=tpcl->TreeD();
       
-      AliSimDigits da, *digits=&da;
-      TD->GetBranch("Segment")->SetAddress(&digits);
+        AliSimDigits da, *digits=&da;
+        TD->GetBranch("Segment")->SetAddress(&digits);
 
-      Int_t *count = new Int_t[np];
-      Int_t i;
-      for (i=0; i<np; i++) count[i]=0;
+        Int_t *count = new Int_t[np];
+        Int_t i;
+        for (i=0; i<np; i++) count[i]=0;
 
-      Int_t sectors_by_rows=(Int_t)TD->GetEntries();
-      for (i=0; i<sectors_by_rows; i++) {
+        Int_t sectors_by_rows=(Int_t)TD->GetEntries();
+        for (i=0; i<sectors_by_rows; i++) {
           if (!TD->GetEvent(i)) continue;
           Int_t sec,row;
           digp->AdjustSectorRow(digits->GetID(),sec,row);
-          cerr<<sec<<' '<<row<<"                                     \r";
+         //cerr<<sec<<' '<<row<<'\r';
           digits->First();
           do { //Many thanks to J.Chudoba who noticed this
               Int_t it=digits->CurrentRow(), ip=digits->CurrentColumn();
@@ -457,97 +530,93 @@ good_tracks_tpc(GoodTrackTPC *gt, const Int_t max, const char* evfoldname) {
               }
               count[j]=0;
           }
-      }
-      delete[] count;
-      tpcl->UnloadDigits();
+        }
+        delete[] count;
+        }
+        break;
      }
-      break;
-   default:
-      ::Fatal("AliTPCComparison.C","Invalid TPC version !");
-   }
 
-   rl->LoadKinematics();
-   AliStack* stack = rl->Stack();
-   /** select tracks which are "good" enough **/
-   for (i=0; i<np; i++) {
-      if ((good[i]&0x5000) != 0x5000)
-      if ((good[i]&0x2800) != 0x2800) continue;
-      if ((good[i]&0x7FF ) < good_number) continue;
-
-      TParticle *p = (TParticle*)stack->Particle(i);
-      if (p == 0x0)
-       {
+
+     //****** select tracks which are "good" enough
+     AliStack* stack = rl->Stack();
+     for (i=0; i<np; i++) {
+        if ((good[i]&0x5000) != 0x5000)
+        if ((good[i]&0x2800) != 0x2800) continue;
+        if ((good[i]&0x7FF ) < good_number) continue;
+
+        TParticle *p = (TParticle*)stack->Particle(i);
+        if (p == 0x0) {
          cerr<<"Can not get particle "<<i<<endl;
          continue;
-       }
-      if (p->Pt()<0.100) continue;
-      if (TMath::Abs(p->Pz()/p->Pt())>0.999) continue;
-
-      Int_t j=p->GetFirstMother();
-      if (j>=0) {
-        TParticle *pp = (TParticle*)stack->Particle(j);
-        if (pp == 0x0)
-         {
-           cerr<<"Can not get particle "<<j<<endl;
-           continue;
-         }
-        if (pp->GetFirstMother()>=0) continue;//only one decay is allowed
-       /*  for cascade hyperons only
-        Int_t jj=pp->GetFirstMother();
-        if (jj>=0) {
-          TParticle *ppp = (TParticle*)stack->Particle(jj);
-          if (ppp->GetFirstMother()>=0) continue;//two decays are allowed
         }
-       */
-      }
+        if (p->Pt()<0.100) continue;
+        if (TMath::Abs(p->Pz()/p->Pt())>0.999) continue;
 
-      gt[nt].lab=i;
-      gt[nt].code=p->GetPdgCode();
-      gt[nt].px=0.; gt[nt].py=0.; gt[nt].pz=0.;
-      gt[nt].x=0.; gt[nt].y=0.; gt[nt].z=0.;
-      nt++;
-      if (nt==max) {cerr<<"Too many good tracks !\n"; break;}
-      cerr<<np-i<<"                \r";
-   }
-   rl->UnloadKinematics();
+        Double_t vx=p->Vx(),vy=p->Vy(),vz=p->Vz();
+        if (TMath::Sqrt(vx*vx+vy*vy)>3.5) continue;
+        if (TMath::Abs(vz) > 50.) continue;
 
-   /** check if there is also information at the entrance of the TPC **/
-   
-   rl->LoadTrackRefs();
-   TTree *TR=rl->TreeTR();
-   TBranch *branch=TR->GetBranch("TPC");
-   if (branch==0) {
-      ::Fatal("AliTPCComparison.C::good_tracks_tpc","No track references !");
-   }
-   TClonesArray *references=new TClonesArray("AliTrackReference",1000);
-   branch->SetAddress(&references);
-   np=(Int_t)TR->GetEntries();
-   for (i=0; i<np; i++) {
-      references->Clear();
-      TR->GetEvent(i);
-      Int_t nref=references->GetEntriesFast();
-      if (nref==0) continue;
-      AliTrackReference *ref=(AliTrackReference*)references->UncheckedAt(0);
-
-      Int_t j, lab=ref->Label();
-      for (j=0; j<nt; j++) {if (gt[j].lab==lab) break;}
-      if (j==nt) continue;         
-
-      // (px,py,pz) - in global coordinate system, (x,y,z) - in local !
-      gt[j].px=ref->Px(); gt[j].py=ref->Py(); gt[j].pz=ref->Pz();
-      gt[j].x = ref->LocalX();
-      gt[j].y = ref->LocalY();
-      gt[j].z = ref->Z();
-   }
+        AliTrackReference *ref=new((*refs)[nt]) AliTrackReference();
+
+        ref->SetLabel(i);
+        Int_t pdg=p->GetPdgCode();
+        ref->SetLength(pdg);  //This will the particle's PDG !
+        ref->SetMomentum(0.,0.,0.);  
+        ref->SetPosition(0.,0.,0.);
+
+        nt++;
+     }
+
+     //**** check if there is also information at the entrance of the TPC
+     TTree *TR=rl->TreeTR();
+     TBranch *branch=TR->GetBranch("TrackReferences");
+     if (branch==0) {
+        ::Error("GoodTracksTPC","No track references !");
+        delete rl;
+        return 5;
+     }
+     TClonesArray tpcdummy("AliTrackReference",1000), *tpcRefs=&tpcdummy;
+     branch->SetAddress(&tpcRefs);
+     Int_t nr=(Int_t)TR->GetEntries();
+     for (Int_t r=0; r<nr; r++) {
+         //cerr<<r<<' '<<nr<<'\r';
+         TR->GetEvent(r);
+
+        Int_t nref = tpcRefs->GetEntriesFast();
+         if (!nref) continue;
+         AliTrackReference *tpcRef= 0x0;        
+        for (Int_t iref=0; iref<nref; ++iref) {
+          tpcRef = (AliTrackReference*)tpcRefs->UncheckedAt(iref);
+          if (tpcRef->DetectorId() == AliTrackReference::kTPC) break;
+          tpcRef = 0x0;
+        }
+
+        if (!tpcRef) continue;
+
+         Int_t j;
+        AliTrackReference *ref=0;
+         for (j=0; j<nt; j++) {
+          ref=(AliTrackReference *)refs->UncheckedAt(j);
+           if (ref->Label()==tpcRef->Label()) break;
+           ref=0;
+        }  
+         if (ref==0) continue;
+
+         ref->SetMomentum(tpcRef->Px(),tpcRef->Py(),tpcRef->Pz());
+         ref->SetPosition(tpcRef->LocalX(),tpcRef->LocalY(),tpcRef->Z());
+
+        tpcRefs->Clear();
+     }
+
+     tpcTree.Fill();
+
+     delete[] good;
+   } //****** end of the loop over generated events
 
-   delete references;
-   delete[] good;
    
-   tpcl->UnloadHits();
-   rl->UnloadTrackRefs();
-   rl->UnloadgAlice();
+   tpcTree.Write();
+   file->Close();
 
-   gBenchmark->Stop("AliTPCComparison");
-   gBenchmark->Show("AliTPCComparison");   
-   return nt;
+   delete rl;
+   return 0;
 }