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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  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 "TList.h"
  21 #include "TMath.h"
  22 #include "TProfile.h"
  23 #include "TVector2.h"
  24
  25 class TH1F;
  26
  27 #include "AliFlowCommonConstants.h"    //needed as include
  28 #include "AliFlowEventSimple.h"
  29 #include "AliFlowTrackSimple.h"
  30 #include "AliFlowCommonHist.h"
  31 //#include "AliFlowCommonHistResults.h"
  32 #include "AliFlowAnalysisWithScalarProduct.h"
  33
  34 class AliFlowVector;
  35
  36 // AliFlowAnalysisWithScalarProduct:
  37 // Description:
  38 // Maker to analyze Flow with the Scalar product method.
  39 //
  40 // author: N. van der Kolk (kolk@nikhef.nl)
  41
  42 ClassImp(AliFlowAnalysisWithScalarProduct)
  43
  44   //-----------------------------------------------------------------------
  45
  46  AliFlowAnalysisWithScalarProduct::AliFlowAnalysisWithScalarProduct():
  47    fEventNumber(0),
  48    fDebug(kFALSE),
  49    fHistList(NULL),
  50    fHistProUQ(NULL),
  51    fCommonHists(NULL)
  52 {
  53   // Constructor.
  54   fHistList = new TList();
  55 }
  56  //-----------------------------------------------------------------------
  57
  58
  59  AliFlowAnalysisWithScalarProduct::~AliFlowAnalysisWithScalarProduct()
  60  {
  61    //destructor
  62    delete fHistList;
  63  }
  64
  65
  66 //-----------------------------------------------------------------------
  67
  68 void AliFlowAnalysisWithScalarProduct::WriteHistograms(TString* outputFileName)
  69 {
  70  //store the final results in output .root file
  71
  72   TFile *output = new TFile(outputFileName->Data(),"RECREATE");
  73   output->WriteObject(fHistList, "cobjSP","SingleKey");
  74   delete output;
  75 }
  76
  77 //-----------------------------------------------------------------------
  78 void AliFlowAnalysisWithScalarProduct::Init() {
  79
  80   //Define all histograms
  81   cout<<"---Analysis with the Scalar Product Method--- Init"<<endl;
  82
  83   Int_t iNbinsPt = AliFlowCommonConstants::GetNbinsPt();
  84   Double_t  dPtMin = AliFlowCommonConstants::GetPtMin();
  85   Double_t  dPtMax = AliFlowCommonConstants::GetPtMax();
  86
  87   fHistProUQ = new TProfile("Flow_UQ_SP","Flow_UQ_SP",iNbinsPt,dPtMin,dPtMax);
  88   fHistProUQ->SetXTitle("p_t (GeV)");
  89   fHistProUQ->SetYTitle("<uQ>");
  90   fHistList->Add(fHistProUQ);
  91
  92   fCommonHists = new AliFlowCommonHist("AliFlowCommonHistSP");
  93   fHistList->Add(fCommonHists);
  94
  95   //fCommonHistsRes = new AliFlowCommonHistResults("SP");
  96
  97   fEventNumber = 0;  //set number of events to zero
  98 }
  99
 100 //-----------------------------------------------------------------------
 101
 102 void AliFlowAnalysisWithScalarProduct::Make(AliFlowEventSimple* anEvent) {
 103
 104   //Fill histogram
 105   if (anEvent) {
 106
 107     //fill control histograms
 108     fCommonHists->FillControlHistograms(anEvent);
 109
 110     //get the Q vector from the FlowEvent
 111     AliFlowVector vQ = anEvent->GetQ();
 112
 113     //loop over the tracks of the event
 114     AliFlowTrackSimple*   pTrack = NULL;
 115     Int_t iNumberOfTracks = anEvent->NumberOfTracks();
 116     for (Int_t i=0;i<iNumberOfTracks;i++)
 117       {
 118         pTrack = anEvent->GetTrack(i) ;
 119         if (pTrack){
 120           if (pTrack->UseForDifferentialFlow()) {
 121           Double_t dPhi = pTrack->Phi();
 122
 123           //calculate vU
 124           TVector2 vU;
 125           Double_t dUX = TMath::Cos(2*dPhi);
 126           Double_t dUY = TMath::Sin(2*dPhi);
 127           vU.Set(dUX,dUY);
 128           Double_t dModulus = vU.Mod();
 129           if (dModulus!=0.) vU.Set(dUX/dModulus,dUY/dModulus);  // make length 1
 130           else cerr<<"dModulus is zero!"<<endl;
 131
 132           TVector2 vQm = vQ;
 133           //subtrackt particle from the flowvector if used to define it
 134           if (pTrack->UseForIntegratedFlow()) {
 135             Double_t dQmX = vQm.X() - dUX;
 136             Double_t dQmY = vQm.Y() - dUY;
 137             vQm.Set(dQmX,dQmY);
 138           }
 139
 140           //dUQ = scalar product of vU and vQm
 141           Double_t dUQ = vU * vQm;
 142           Double_t dPt = pTrack->Pt();
 143           //fill the profile histogram
 144           fHistProUQ->Fill(dPt,dUQ);
 145           }
 146         }//track selected
 147       }//loop over tracks
 148
 149     fEventNumber++;
 150     cout<<"@@@@@ "<<fEventNumber<<" events processed"<<endl;
 151   }
 152 }
 153
 154   //--------------------------------------------------------------------
 155 void AliFlowAnalysisWithScalarProduct::Finish() {
 156
 157   //*************make histograms etc.
 158   if (fDebug) cout<<"AliFlowAnalysisWithScalarProduct::Terminate()"<<endl;
 159
 160   //  fHistProUQ->Draw();
 161
 162   cout<<".....finished"<<endl;
 163  }
 164
 165