1 #include "dNdEtaAnalysis.h"
9 //____________________________________________________________________
10 ClassImp(dNdEtaAnalysis)
12 //____________________________________________________________________
13 dNdEtaAnalysis::dNdEtaAnalysis(Char_t* name) {
15 fName = TString(name);
17 hEtaVsVtx = new TH2F("eta_vs_vtx","",80,-20,20,120,-6,6);
18 hEtaVsVtxUncorrected = new TH2F("eta_vs_vtx_uncorrected","",80,-20,20,120,-6,6);
19 hVtx = hEtaVsVtx->ProjectionX("vtx");
20 hdNdEta = hEtaVsVtx->ProjectionY("dNdEta");
22 hEtaVsVtx->SetXTitle("vtx z [cm]");
23 hEtaVsVtx->SetYTitle("#eta");
24 hVtx->SetXTitle("vtx z [cm]");
25 hdNdEta->SetXTitle("#eta");
26 hdNdEta->SetYTitle("dN/d#eta");
32 //____________________________________________________________________
34 dNdEtaAnalysis::FillTrack(Float_t vtx, Float_t eta, Float_t weight) {
35 hEtaVsVtx->Fill(vtx, eta, weight);
36 hEtaVsVtxUncorrected->Fill(vtx,eta);
39 //____________________________________________________________________
41 dNdEtaAnalysis::FillEvent(Float_t vtx) {
45 //____________________________________________________________________
47 dNdEtaAnalysis::Finish() {
49 // first normalize with n events (per vtx)
50 for (Int_t i_vtx=0; i_vtx<=hVtx->GetNbinsX(); i_vtx++) {
51 Float_t nEvents = hVtx->GetBinContent(i_vtx);
52 Float_t nEventsError = hVtx->GetBinError(i_vtx);
54 if (nEvents==0) continue;
56 for (Int_t i_eta=0; i_eta<=hEtaVsVtx->GetNbinsY(); i_eta++) {
57 Float_t value = hEtaVsVtx->GetBinContent(i_vtx, i_eta)/nEvents;
58 if (value==0) continue;
59 Float_t error = hEtaVsVtx->GetBinError(i_vtx, i_eta)/nEvents;
60 error = TMath::Sqrt(TMath::Power(hEtaVsVtx->GetBinError(i_vtx, i_eta)/
61 hEtaVsVtx->GetBinContent(i_vtx, i_eta),2) +
62 TMath::Power(nEventsError/nEvents,2));
63 hEtaVsVtx->SetBinContent(i_vtx, i_eta, value);
64 hEtaVsVtx->SetBinError(i_vtx, i_eta, error);
68 // then take the wieghted average for each eta
69 // is this the right way to do it???
70 for (Int_t i_eta=0; i_eta<=hEtaVsVtx->GetNbinsY(); i_eta++) {
72 Float_t sumError2 = 0;
73 Int_t nMeasurements = 0;
78 for (Int_t i_vtx=0; i_vtx<=hVtx->GetNbinsX(); i_vtx++) {
79 if (hVtx->GetBinContent(i_vtx)==0) continue;
80 if (hEtaVsVtx->GetBinContent(i_vtx, i_eta)==0) continue;
82 Float_t w = 1/TMath::Power(hEtaVsVtx->GetBinError(i_vtx, i_eta),2);
83 sum_xw = sum_xw + hEtaVsVtx->GetBinContent(i_vtx, i_eta)*w;
86 sum = sum + hEtaVsVtx->GetBinContent(i_vtx, i_eta);
87 sumError2 = sumError2 + TMath::Power(hEtaVsVtx->GetBinError(i_vtx, i_eta),2);
93 if (nMeasurements!=0) {
94 dndeta = sum/Float_t(nMeasurements);
95 error = TMath::Sqrt(sumError2)/Float_t(nMeasurements);
97 dndeta = sum_xw/sum_w;
98 error = 1/TMath::Sqrt(sum_w);
100 dndeta = dndeta/hdNdEta->GetBinWidth(i_eta);
101 error = error/hdNdEta->GetBinWidth(i_eta);
103 hdNdEta->SetBinContent(i_eta, dndeta);
104 hdNdEta->SetBinError(i_eta, error);
112 //____________________________________________________________________
114 dNdEtaAnalysis::SaveHistograms() {
116 gDirectory->mkdir(fName.Data());
117 gDirectory->cd(fName.Data());
123 gDirectory->cd("../");
126 //____________________________________________________________________
127 void dNdEtaAnalysis::DrawHistograms()
129 TCanvas* canvas = new TCanvas("dNdEtaAnalysis", "dNdEtaAnalysis", 800, 800);
130 canvas->Divide(2, 2);
134 hEtaVsVtx->Draw("COLZ");
137 if (hEtaVsVtxUncorrected)
138 hEtaVsVtxUncorrected->Draw("COLZ");