PWG2/FLOW/AliFlowAnalysisWithScalarProduct.cxx

   1 /*************************************************************************
   2 * Copyright(c) 1998-2008, ALICE Experiment at CERN, All rights reserved. *
   3 *                                                                        *
   4 * Author: The ALICE Off-line Project.                                    *
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   6 *                                                                        *
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  10 * copies and that both the copyright notice and this permission notice   *
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  12 * about the suitability of this software for any purpose. It is          *
  13 * provided "as is" without express or implied warranty.                  *
  14 **************************************************************************/
  15
  16 #define AliFlowAnalysisWithScalarProduct_cxx
  17
  18 #include "Riostream.h"  //needed as include
  19 #include "TFile.h"      //needed as include
  20 #include "TMath.h"
  21 #include "TProfile.h"
  22 #include "TVector2.h"
  23
  24 class TH1F;
  25
  26 #include "AliFlowCommonConstants.h"    //needed as include
  27 #include "AliFlowEventSimple.h"
  28 #include "AliFlowTrackSimple.h"
  29 #include "AliFlowCommonHist.h"
  30 //#include "AliFlowCommonHistResults.h"
  31 #include "AliFlowAnalysisWithScalarProduct.h"
  32
  33 class AliFlowVector;
  34
  35 // AliFlowAnalysisWithScalarProduct:
  36 // Description:
  37 // Maker to analyze Flow with the Scalar product method.
  38 //
  39 // author: N. van der Kolk (kolk@nikhef.nl)
  40
  41 ClassImp(AliFlowAnalysisWithScalarProduct)
  42
  43   //-----------------------------------------------------------------------
  44
  45  AliFlowAnalysisWithScalarProduct::AliFlowAnalysisWithScalarProduct():
  46    fEventNumber(0),
  47    fTrack(NULL),
  48    fDebug(kFALSE),
  49    fHistFileName(0),
  50    fHistFile(NULL),
  51    fHistProUQ(NULL),
  52    fCommonHists(NULL)
  53 {
  54
  55   // Constructor.
  56   fQ.Set(0.,0.);           // flow vector
  57   fU.Set(0.,0.);           // particle unit vector
  58
  59 }
  60  //-----------------------------------------------------------------------
  61
  62
  63  AliFlowAnalysisWithScalarProduct::~AliFlowAnalysisWithScalarProduct()
  64  {
  65    //destructor
  66
  67  }
  68
  69
  70 //-----------------------------------------------------------------------
  71 void AliFlowAnalysisWithScalarProduct::Init() {
  72
  73   //Define all histograms
  74   cout<<"---Analysis with the Scalar Product Method---"<<endl;
  75
  76   Int_t fNbinsPt = AliFlowCommonConstants::GetNbinsPt();
  77   Double_t  fPtMin = AliFlowCommonConstants::GetPtMin();
  78   Double_t  fPtMax = AliFlowCommonConstants::GetPtMax();
  79
  80   // analysis file (output)
  81   fHistFile = new TFile(fHistFileName.Data(),"RECREATE") ;
  82
  83   fHistProUQ = new TProfile("Flow_UQ_SP","Flow_UQ_SP",fNbinsPt,fPtMin,fPtMax);
  84   fHistProUQ->SetXTitle("p_t (GeV)");
  85   fHistProUQ->SetYTitle("<uQ>");
  86
  87   fCommonHists = new AliFlowCommonHist("SP");
  88   //fCommonHistsRes = new AliFlowCommonHistResults("SP");
  89
  90   fEventNumber = 0;  //set number of events to zero
  91
  92 }
  93
  94 //-----------------------------------------------------------------------
  95
  96 void AliFlowAnalysisWithScalarProduct::Make(AliFlowEventSimple* anEvent) {
  97
  98   //Fill histogram
  99   if (anEvent) {
 100
 101     //fill control histograms
 102     fCommonHists->FillControlHistograms(anEvent);
 103
 104     //get the Q vector from the FlowEvent
 105     fQ = anEvent->GetQ();
 106     //Double_t fMult =  fQ.GetMult();
 107
 108     //loop over the tracks of the event
 109     Int_t fNumberOfTracks = anEvent->NumberOfTracks();
 110     for (Int_t i=0;i<fNumberOfTracks;i++)
 111       {
 112
 113         fTrack = anEvent->GetTrack(i) ;
 114         if (fTrack){
 115           if (fTrack->UseForDifferentialFlow()) {
 116           Double_t fPhi = fTrack->Phi();
 117
 118           //calculate fU
 119           Double_t fUX = TMath::Cos(2*fPhi);
 120           Double_t fUY = TMath::Sin(2*fPhi);
 121           fU.Set(fUX,fUY);
 122           Double_t fModulus = fU.Mod();
 123           if (fModulus!=0.) fU.Set(fUX/fModulus,fUY/fModulus);  // make length 1
 124           else cerr<<"fModulus is zero!"<<endl;
 125
 126           TVector2 fQm = fQ;
 127           //subtrackt particle from the flowvector if used to define it
 128           if (fTrack->UseForIntegratedFlow()) {
 129             Double_t fQmX = fQm.X() - fUX;
 130             Double_t fQmY = fQm.Y() - fUY;
 131             fQm.Set(fQmX,fQmY);
 132           }
 133
 134           //Double_t fUQ = scalar product of fU and fQm
 135           Double_t fUQ = fU*fQm;
 136           Double_t fPt = fTrack->Pt();
 137           //fill the profile histogram
 138           fHistProUQ->Fill(fPt,fUQ);
 139           }
 140         }//track selected
 141       }//loop over tracks
 142
 143     fEventNumber++;
 144     cout<<"@@@@@ "<<fEventNumber<<" events processed"<<endl;
 145   }
 146 }
 147
 148   //--------------------------------------------------------------------
 149 void AliFlowAnalysisWithScalarProduct::Finish() {
 150
 151   //*************make histograms etc.
 152   if (fDebug) cout<<"AliFlowAnalysisWithScalarProduct::Terminate()"<<endl;
 153
 154   fHistProUQ->Draw();
 155
 156   // write to file
 157   fHistFile->Write();
 158
 159   cout<<".....finished"<<endl;
 160  }
 161
 162