handle reference tracks correctly for background subtraction and randomized events

[u/mrichter/AliRoot.git] / PWG4 / JetTasks / AliPWG4HighPtSpectra.cxx

/**************************************************************************
 * Copyright(c) 1998-1999, ALICE Experiment at CERN, All rights reserved. *
 *                                                                        *
 * Author: The ALICE Off-line Project.                                    *
 * Contributors are mentioned in the code where appropriate.              *
 *                                                                        *
 * Permission to use, copy, modify and distribute this software and its   *
 * documentation strictly for non-commercial purposes is hereby granted   *
 * without fee, provided that the above copyright notice appears in all   *
 * copies and that both the copyright notice and this permission notice   *
 * appear in the supporting documentation. The authors make no claims     *
 * about the suitability of this software for any purpose. It is          *
 * provided "as is" without express or implied warranty.                  *
 **************************************************************************/

//-----------------------------------------------------------------------
// Example of task (running locally, on AliEn and CAF),
// which provides standard way of calculating acceptance and efficiency
// between different steps of the procedure.
// The ouptut of the task is a AliCFContainer from which the efficiencies
// can be calculated
//-----------------------------------------------------------------------
// Author : Marta Verweij - UU
//-----------------------------------------------------------------------


#ifndef ALIPWG4HIGHPTSPECTRA_CXX
#define ALIPWG4HIGHPTSPECTRA_CXX

#include "AliPWG4HighPtSpectra.h"

#include "TVector3.h"
#include <iostream>
#include "TH1.h"
#include "TH2.h"
#include "TH3.h"
#include "TProfile.h"
#include "TList.h"
#include "TChain.h"
#include "TKey.h"
#include "TSystem.h"
#include "TFile.h"

#include "AliAnalysisManager.h"
#include "AliESDInputHandler.h"
#include "AliESDtrack.h"
#include "AliESDtrackCuts.h"
#include "AliExternalTrackParam.h"

#include "AliLog.h"

#include "AliStack.h"
#include "TParticle.h"
#include "AliMCEvent.h"
#include "AliMCEventHandler.h"
#include "AliCFContainer.h"
#include "AliGenPythiaEventHeader.h"
#include "AliGenCocktailEventHeader.h"
//#include "$ALICE_ROOT/PWG4/JetTasks/AliAnalysisHelperJetTasks.h"

//#include <iostream>
using namespace std; //required for resolving the 'cout' symbol

ClassImp(AliPWG4HighPtSpectra)

//__________________________________________________________________________
AliPWG4HighPtSpectra::AliPWG4HighPtSpectra() : AliAnalysisTask("AliPWG4HighPtSpectra", ""), 
  fReadAODData(0),
  fCFManagerPos(0x0),
  fCFManagerNeg(0x0),
  fESD(0x0),
  fMC(0x0),
  fStack(0x0),
  fVtx(0x0),
  fTrackType(0),
  fTrackCuts(0x0),
  fTrackCutsTPConly(0x0),
  fAvgTrials(1),
  fHistList(0),
  fNEventAll(0),
  fNEventSel(0),
  fNEventReject(0),
  fh1Xsec(0),
  fh1Trials(0),
  fh1PtHard(0),
  fh1PtHardTrials(0)
{
  //
  //Default ctor
  //
}
//___________________________________________________________________________
AliPWG4HighPtSpectra::AliPWG4HighPtSpectra(const Char_t* name) :
  AliAnalysisTask(name,""),
  fReadAODData(0),
  fCFManagerPos(0x0),
  fCFManagerNeg(0x0),
  fESD(0x0),
  fMC(0x0),
  fStack(0x0),
  fVtx(0x0),
  fTrackType(0),
  fTrackCuts(0x0),
  fTrackCutsTPConly(0x0),
  fAvgTrials(1),
  fHistList(0),
  fNEventAll(0),
  fNEventSel(0),
  fNEventReject(0),
  fh1Xsec(0),
  fh1Trials(0),
  fh1PtHard(0),
  fh1PtHardTrials(0)
{
  //
  // Constructor. Initialization of Inputs and Outputs
  //
  AliDebug(2,Form("AliPWG4HighPtSpectra Calling Constructor"));
  // Input slot #0 works with a TChain ESD
  DefineInput(0, TChain::Class());
  // Output slot #0 writes into a TList
  DefineOutput(0,TList::Class());
  // Output slot #1, #2 writes into a AliCFContainer
  DefineOutput(1,AliCFContainer::Class());
  DefineOutput(2,AliCFContainer::Class());
  // Output slot #3 writes into a AliESDtrackCuts
  DefineOutput(3, AliESDtrackCuts::Class());
  DefineOutput(4, AliESDtrackCuts::Class());
}

//________________________________________________________________________
void AliPWG4HighPtSpectra::LocalInit()
{
  //
  // Only called once at beginning
  //
  PostData(3,fTrackCuts);
  PostData(4,fTrackCutsTPConly);
}

//________________________________________________________________________
void AliPWG4HighPtSpectra::ConnectInputData(Option_t *) 
{
  // Connect ESD here
  // Called once
  AliDebug(2,Form(">> AliPWG4HighPtSpectra::ConnectInputData \n"));

  TTree* tree = dynamic_cast<TTree*> (GetInputData(0));
  if (!tree) {
    AliDebug(2,Form( "ERROR: Could not read chain from input slot 0 \n"));
    return;
  }

  AliESDInputHandler *esdH = dynamic_cast<AliESDInputHandler*> (AliAnalysisManager::GetAnalysisManager()->GetInputEventHandler());

  if (!esdH) {
    AliDebug(2,Form("ERROR: Could not get ESDInputHandler"));
    return;
  } else
    fESD = esdH->GetEvent();
  
  AliMCEventHandler *eventHandler = dynamic_cast<AliMCEventHandler*> (AliAnalysisManager::GetAnalysisManager()->GetMCtruthEventHandler());
  if (!eventHandler) {
    AliDebug(2,Form( "ERROR: Could not retrieve MC event handler \n"));
  }
  else
    fMC = eventHandler->MCEvent();

}

//________________________________________________________________________
Bool_t AliPWG4HighPtSpectra::SelectEvent() {
  //
  // Decide if event should be selected for analysis
  //

  // Checks following requirements:
  // - fESD available
  // - trigger info from AliPhysicsSelection
  // - number of reconstructed tracks > 1
  // - primary vertex reconstructed
  // - z-vertex < 10 cm

  Bool_t selectEvent = kTRUE;

  //fESD object available?
  if (!fESD) {
    AliDebug(2,Form("ERROR: fInputEvent not available\n"));
    fNEventReject->Fill("noESD",1);
    selectEvent = kFALSE;
    return selectEvent;
  }

  //Trigger
  UInt_t isSelected = ((AliInputEventHandler*)(AliAnalysisManager::GetAnalysisManager()->GetInputEventHandler()))->IsEventSelected();
  if(!(isSelected&AliVEvent::kMB)) { //Select collison candidates
    AliDebug(2,Form(" Trigger Selection: event REJECTED ... "));
    fNEventReject->Fill("Trigger",1);
    selectEvent = kFALSE;
    return selectEvent;
  }

  //Check if number of reconstructed tracks is larger than 1
  if(!fESD->GetNumberOfTracks() || fESD->GetNumberOfTracks()<2)  {
    fNEventReject->Fill("NTracks<2",1);
    selectEvent = kFALSE;
    return selectEvent;
  }

  //Check if vertex is reconstructed
  fVtx = fESD->GetPrimaryVertexSPD();

  if(!fVtx) {
    fNEventReject->Fill("noVTX",1);
    selectEvent = kFALSE;
    return selectEvent;
  }

  if(!fVtx->GetStatus()) {
    fNEventReject->Fill("VtxStatus",1);
    selectEvent = kFALSE;
    return selectEvent;
  }

  // Need vertex cut
  //  TString vtxName(fVtx->GetName());
  if(fVtx->GetNContributors()<2) {
    fNEventReject->Fill("NCont<2",1);
    selectEvent = kFALSE;
    return selectEvent;
  }

  //Check if z-vertex < 10 cm
  double primVtx[3];
  fVtx->GetXYZ(primVtx);
  if(TMath::Sqrt(primVtx[0]*primVtx[0] + primVtx[1]*primVtx[1])>1. || TMath::Abs(primVtx[2]>10.)){
    fNEventReject->Fill("ZVTX>10",1);
    selectEvent = kFALSE;
    return selectEvent;
  }

  return selectEvent;

}

//_________________________________________________
void AliPWG4HighPtSpectra::Exec(Option_t *)
{
  //
  // Main loop function
  //
  AliDebug(2,Form(">> AliPWG4HighPtSpectra::Exec \n"));  

  // All events without selection
  fNEventAll->Fill(0.);

  if(!SelectEvent()) {
    fNEventReject->Fill("NTracks<2",1);
    // Post output data
    PostData(0,fHistList);
    PostData(1,fCFManagerPos->GetParticleContainer());
    PostData(2,fCFManagerNeg->GetParticleContainer());
    return;
  }

  //MCEvent available? 
  //if yes: get stack
  if(fMC) {
    AliDebug(2,Form("MC particles: %d", fMC->GetNumberOfTracks()));
    fStack = fMC->Stack();                //Particles Stack
    AliDebug(2,Form("MC particles stack: %d", fStack->GetNtrack()));
  }

  // ---- Get MC Header information (for MC productions in pThard bins) ----
  Double_t ptHard = 0.;
  Double_t nTrials = 1; // trials for MC trigger weight for real data
  
  if(fMC){
    AliGenPythiaEventHeader*  pythiaGenHeader = GetPythiaEventHeader(fMC);
     if(pythiaGenHeader){
       nTrials = pythiaGenHeader->Trials();
       ptHard  = pythiaGenHeader->GetPtHard();
       
       fh1PtHard->Fill(ptHard);
       fh1PtHardTrials->Fill(ptHard,nTrials);
       
       fh1Trials->Fill("#sum{ntrials}",fAvgTrials);
     }
  }
  
  Int_t nTracks = fESD->GetNumberOfTracks();
  AliDebug(2,Form("nTracks %d", nTracks));

  if(!fTrackCuts) { 
    fNEventReject->Fill("noTrackCuts",1);
    // Post output data
    PostData(0,fHistList);
    PostData(1,fCFManagerPos->GetParticleContainer());
    PostData(2,fCFManagerNeg->GetParticleContainer());
    return;
  }

  // Selected events for analysis
  fNEventSel->Fill(0.);
  
  
  Double_t containerInputRec[3]       = {0.,0.,0.};
  Double_t containerInputTPConly[3]   = {0.,0.,0.};
  Double_t containerInputMC[3]        = {0.,0.,0.};
  Double_t containerInputRecMC[3]     = {0.,0.,0.};
  Double_t containerInputTPConlyMC[3] = {0.,0.,0.};

  //Now go to rec level
  for (Int_t iTrack = 0; iTrack<nTracks; iTrack++) 
    {   
      if(!fESD->GetTrack(iTrack) ) continue;
      AliESDtrack* track = fESD->GetTrack(iTrack);
      if(!(AliExternalTrackParam *)track->GetTPCInnerParam()) continue;
      AliExternalTrackParam *trackTPC = (AliExternalTrackParam *)track->GetTPCInnerParam();
      //fTrackType==1 use constrained TPConly track
      AliESDtrack* trackTPCESD = fTrackCutsTPConly->GetTPCOnlyTrack(fESD, track->GetID());
      if(fTrackType==1) {
	if(!trackTPCESD) {
	  delete trackTPCESD;
	  continue;
	}
	AliExternalTrackParam exParam;
	Bool_t relate = trackTPCESD->RelateToVertexTPC(fVtx,fESD->GetMagneticField(),kVeryBig,&exParam);
	if( !relate ) {
	  delete track;
	  continue;
	}
	trackTPCESD->Set(exParam.GetX(),exParam.GetAlpha(),exParam.GetParameter(),exParam.GetCovariance());


      }
      if(!trackTPCESD) {
	delete trackTPCESD;
	continue;
      }


      if(!track || !trackTPC) continue;


      //fill the container
      containerInputRec[0] = track->Pt();
      containerInputRec[1] = track->Phi();
      containerInputRec[2] = track->Eta();
    
      //Store TPC Inner Params for TPConly tracks
      containerInputTPConly[0] = trackTPCESD->Pt();
      containerInputTPConly[1] = trackTPCESD->Phi();
      containerInputTPConly[2] = trackTPCESD->Eta();

      if(trackTPCESD) {
	if (fTrackCutsTPConly->AcceptTrack(trackTPCESD)) {
	  if(trackTPC->GetSign()>0.) fCFManagerPos->GetParticleContainer()->Fill(containerInputTPConly,kStepReconstructedTPCOnly);
	  if(trackTPC->GetSign()<0.) fCFManagerNeg->GetParticleContainer()->Fill(containerInputTPConly,kStepReconstructedTPCOnly);

	  //Only fill the MC containers if MC information is available
	  if(fMC) {
	    Int_t label = TMath::Abs(track->GetLabel());
	    TParticle *particle = fStack->Particle(label) ;
	    if(!particle) continue;
	    
	    containerInputTPConlyMC[0] = particle->Pt();      
	    containerInputTPConlyMC[1] = particle->Phi();      
	    containerInputTPConlyMC[2] = particle->Eta();  
	    
	    //Container with primaries
	    if(fStack->IsPhysicalPrimary(label)) {
	      if(particle->GetPDG()->Charge()>0.) {
		fCFManagerPos->GetParticleContainer()->Fill(containerInputTPConlyMC,kStepReconstructedTPCOnlyMC);
	      }
	      if(particle->GetPDG()->Charge()<0.) {
		fCFManagerNeg->GetParticleContainer()->Fill(containerInputTPConlyMC,kStepReconstructedTPCOnlyMC);
	      }
	    }
	  }
	  
	}
      }

      if (fTrackCuts->AcceptTrack(track)) {
	if(track->GetSign()>0.) fCFManagerPos->GetParticleContainer()->Fill(containerInputRec,kStepReconstructed);
	if(track->GetSign()<0.) fCFManagerNeg->GetParticleContainer()->Fill(containerInputRec,kStepReconstructed);

  	
	//Only fill the MC containers if MC information is available
	if(fMC) {
	  Int_t label = TMath::Abs(track->GetLabel());
	  TParticle *particle = fStack->Particle(label) ;
	  if(!particle) continue;

	  containerInputRecMC[0] = particle->Pt();      
	  containerInputRecMC[1] = particle->Phi();      
	  containerInputRecMC[2] = particle->Eta();  

	  //Container with primaries
	  if(fStack->IsPhysicalPrimary(label)) {
	    if(particle->GetPDG()->Charge()>0.) {
	      fCFManagerPos->GetParticleContainer()->Fill(containerInputRecMC,kStepReconstructedMC);
	    }
	    if(particle->GetPDG()->Charge()<0.) {
	      fCFManagerNeg->GetParticleContainer()->Fill(containerInputRecMC,kStepReconstructedMC);
	    }
	  }

	  //Container with secondaries
	  if (!fStack->IsPhysicalPrimary(label) ) {
	    if(particle->GetPDG()->Charge()>0.) {
	      fCFManagerPos->GetParticleContainer()->Fill(containerInputRec,kStepSecondaries);
	    }
	    if(particle->GetPDG()->Charge()<0.) {
	      fCFManagerNeg->GetParticleContainer()->Fill(containerInputRec,kStepSecondaries);
	    }
	  }
	}
	
      }//trackCuts

      delete trackTPCESD;
    }//track loop
  

  //Fill MC containters if particles are findable
  if(fMC) {
    for(int iPart = 1; iPart<(fMC->GetNumberOfPrimaries()); iPart++) {
      AliMCParticle *mcPart  = (AliMCParticle*)fMC->GetTrack(iPart);
      if(!mcPart) continue;
      //fill the container
      containerInputMC[0] = mcPart->Pt();
      containerInputMC[1] = mcPart->Phi();      
      containerInputMC[2] = mcPart->Eta();  
      
      if(fStack->IsPhysicalPrimary(iPart)) {
	if(mcPart->Charge()>0. && fCFManagerPos->CheckParticleCuts(kStepMCAcceptance,mcPart)) fCFManagerPos->GetParticleContainer()->Fill(containerInputMC,kStepMCAcceptance);
	if(mcPart->Charge()<0. && fCFManagerNeg->CheckParticleCuts(kStepMCAcceptance,mcPart)) fCFManagerNeg->GetParticleContainer()->Fill(containerInputMC,kStepMCAcceptance);
      }
    }
  }
  
  PostData(0,fHistList);
  PostData(1,fCFManagerPos->GetParticleContainer());
  PostData(2,fCFManagerNeg->GetParticleContainer());
  
}
//________________________________________________________________________
Bool_t AliPWG4HighPtSpectra::PythiaInfoFromFile(const char* currFile,Float_t &fXsec,Float_t &fTrials){
  //
  // get the cross section and the trails either from pyxsec.root or from pysec_hists.root
  // This is to called in Notify and should provide the path to the AOD/ESD file
  // Copied from AliAnalysisTaskJetSpectrum2
  //

  TString file(currFile);  
  fXsec = 0;
  fTrials = 1;

  if(file.Contains("root_archive.zip#")){
    Ssiz_t pos1 = file.Index("root_archive",12,TString::kExact);
    Ssiz_t pos = file.Index("#",1,pos1,TString::kExact);
    file.Replace(pos+1,20,"");
  }
  else {
    // not an archive take the basename....
    file.ReplaceAll(gSystem->BaseName(file.Data()),"");
  }
  //  Printf("%s",file.Data());
   
  TFile *fxsec = TFile::Open(Form("%s%s",file.Data(),"pyxsec.root")); // problem that we cannot really test the existance of a file in a archive so we have to lvie with open error message from root
  if(!fxsec){
    // next trial fetch the histgram file
    fxsec = TFile::Open(Form("%s%s",file.Data(),"pyxsec_hists.root"));
    if(!fxsec){
	// not a severe condition but inciate that we have no information
      return kFALSE;
    }
    else{
      // find the tlist we want to be independtent of the name so use the Tkey
      TKey* key = (TKey*)fxsec->GetListOfKeys()->At(0); 
      if(!key){
	fxsec->Close();
	return kFALSE;
      }
      TList *list = dynamic_cast<TList*>(key->ReadObj());
      if(!list){
	fxsec->Close();
	return kFALSE;
      }
      fXsec = ((TProfile*)list->FindObject("h1Xsec"))->GetBinContent(1);
      fTrials  = ((TH1F*)list->FindObject("h1Trials"))->GetBinContent(1);
      fxsec->Close();
    }
  } // no tree pyxsec.root
  else {
    TTree *xtree = (TTree*)fxsec->Get("Xsection");
    if(!xtree){
      fxsec->Close();
      return kFALSE;
    }
    UInt_t   ntrials  = 0;
    Double_t  xsection  = 0;
    xtree->SetBranchAddress("xsection",&xsection);
    xtree->SetBranchAddress("ntrials",&ntrials);
    xtree->GetEntry(0);
    fTrials = ntrials;
    fXsec = xsection;
    fxsec->Close();
  }
  return kTRUE;
}
//________________________________________________________________________
Bool_t AliPWG4HighPtSpectra::Notify()
{
  //
  // Implemented Notify() to read the cross sections
  // and number of trials from pyxsec.root
  // Copied from AliAnalysisTaskJetSpectrum2
  // 

  TTree *tree = AliAnalysisManager::GetAnalysisManager()->GetTree();
  Float_t xsection = 0;
  Float_t ftrials  = 1;

  fAvgTrials = 1;
  if(tree){
    TFile *curfile = tree->GetCurrentFile();
    if (!curfile) {
      Error("Notify","No current file");
      return kFALSE;
    }
    if(!fh1Xsec||!fh1Trials){
      //      Printf("%s%d No Histogram fh1Xsec",(char*)__FILE__,__LINE__);
      return kFALSE;
    }
     PythiaInfoFromFile(curfile->GetName(),xsection,ftrials);
    fh1Xsec->Fill("<#sigma>",xsection);
    // construct a poor man average trials 
    Float_t nEntries = (Float_t)tree->GetTree()->GetEntries();
    if(ftrials>=nEntries && nEntries>0.)fAvgTrials = ftrials/nEntries;
  }  
  return kTRUE;
}

//________________________________________________________________________
AliGenPythiaEventHeader*  AliPWG4HighPtSpectra::GetPythiaEventHeader(AliMCEvent *mcEvent){
  
  if(!mcEvent)return 0;
  AliGenEventHeader* genHeader = mcEvent->GenEventHeader();
  AliGenPythiaEventHeader* pythiaGenHeader = dynamic_cast<AliGenPythiaEventHeader*>(genHeader);
  if(!pythiaGenHeader){
    // cocktail ??
    AliGenCocktailEventHeader* genCocktailHeader = dynamic_cast<AliGenCocktailEventHeader*>(genHeader);
    
    if (!genCocktailHeader) {
      //      AliWarningGeneral(Form(" %s:%d",(char*)__FILE__,__LINE__),"Unknown header type (not Pythia or Cocktail)");
      //      AliWarning(Form("%s %d: Unknown header type (not Pythia or Cocktail)",(char*)__FILE__,__LINE__));
      return 0;
    }
    TList* headerList = genCocktailHeader->GetHeaders();
    for (Int_t i=0; i<headerList->GetEntries(); i++) {
      pythiaGenHeader = dynamic_cast<AliGenPythiaEventHeader*>(headerList->At(i));
      if (pythiaGenHeader)
        break;
    }
    if(!pythiaGenHeader){
      AliWarningGeneral(Form(" %s:%d",(char*)__FILE__,__LINE__),"Pythia event header not found");
      return 0;
    }
  }
  return pythiaGenHeader;

}


//___________________________________________________________________________
void AliPWG4HighPtSpectra::Terminate(Option_t*)
{
  // The Terminate() function is the last function to be called during
  // a query. It always runs on the client, it can be used to present
  // the results graphically or save the results to file.

}

//___________________________________________________________________________
void AliPWG4HighPtSpectra::CreateOutputObjects() {
  //HERE ONE CAN CREATE OUTPUT OBJECTS, IN PARTICULAR IF THE OBJECT PARAMETERS DON'T NEED
  //TO BE SET BEFORE THE EXECUTION OF THE TASK
  //
  AliDebug(2,Form("CreateOutputObjects CreateOutputObjects of task %s", GetName()));

  Bool_t oldStatus = TH1::AddDirectoryStatus();
  TH1::AddDirectory(kFALSE); 

  //slot #1
  OpenFile(0);
  fHistList = new TList();
  fHistList->SetOwner(kTRUE);
  fNEventAll = new TH1F("fNEventAll","NEventAll",1,-0.5,0.5);
  fHistList->Add(fNEventAll);
  fNEventSel = new TH1F("fNEventSel","NEvent Selected for analysis",1,-0.5,0.5);
  fHistList->Add(fNEventSel);

  fNEventReject = new TH1F("fNEventReject","Reason events are rejectected for analysis",20,0,20);
  fHistList->Add(fNEventReject);

  fh1Xsec = new TProfile("fh1Xsec","xsec from pyxsec.root",1,0,1);
  fh1Xsec->GetXaxis()->SetBinLabel(1,"<#sigma>");
  fHistList->Add(fh1Xsec);

  fh1Trials = new TH1F("fh1Trials","trials root file",1,0,1);
  fh1Trials->GetXaxis()->SetBinLabel(1,"#sum{ntrials}");
  fHistList->Add(fh1Trials);

  fh1PtHard       = new TH1F("fh1PtHard","PYTHIA Pt hard;p_{T,hard}",350,-.5,349.5);
  fHistList->Add(fh1PtHard);
  fh1PtHardTrials = new TH1F("fh1PtHardTrials","PYTHIA Pt hard weight with trials;p_{T,hard}",350,-.5,349.5);
  fHistList->Add(fh1PtHardTrials);

  TH1::AddDirectory(oldStatus);   

}

#endif