v2_plot.C

void v2_plot() {
  const int nPtBin=15;
  double pt[nPtBin];
  double v2[nPtBin];
  double v2e[nPtBin];

  ifstream inv2;
  inv2.open("output_v2.txt");
  if(!inv2.good())    cout<<" input fail"<<endl;
  else cout<<" input OK! "<<endl;
  for(int i=0;i<nPtBin;i++){
    inv2>>pt[i];  
    inv2>>v2[i];  
    inv2>>v2e[i];  
//v2[i]=v2[i]*1.35;
  } 

////////////////

////////
  TCanvas *c1 = new TCanvas("c1","c1",1,1,650,550);
  c1->SetFillColor(10);
  c1->SetFrameFillColor(0);
  c1->SetFrameBorderSize(0);
  c1->SetFrameBorderMode(0);
  c1->SetLeftMargin(0.15);
  c1->SetBottomMargin(0.15);
  c1->SetTopMargin(0.02);
  c1->SetRightMargin(0.02);
  //c1->Divide(2,1,0,0);
 gStyle->SetOptStat(0);
  c1->SetTicks(-1);
 TH1D* hist = new TH1D("hist","",200,0.,10.0);
 hist->SetXTitle("p_{T} (GeV/c)");
 hist->SetYTitle("v_{2}{EP}");
 hist->SetMinimum(0.001);
 hist->SetMaximum(0.259);
 hist->GetXaxis()->CenterTitle(1);
 hist->GetYaxis()->CenterTitle(1);
 hist->GetYaxis()->SetTitleOffset(1.1);
 hist->GetXaxis()->SetTitleOffset(0.95);
 hist->GetXaxis()->SetTitleSize(0.066);
 hist->GetYaxis()->SetTitleSize(0.066);
 hist->GetXaxis()->SetLabelSize(0.05);
 hist->GetYaxis()->SetLabelSize(0.05);
 hist->Draw();

  TF1 *V2vsPt = new TF1("V2vsPt","((x/3.4)^1.8/(1+(x/3)^1.8))*(.00005+(1/x)^0.8)",0.2,10);
  V2vsPt->SetLineColor(2);
  V2vsPt->SetLineWidth(2);
  V2vsPt->SetLineStyle(2);
  V2vsPt->Draw("same");

  TGraphErrors *gr2 = new TGraphErrors(nPtBin,pt,v2,0,v2e);
  gr2->SetTitle("");
  gr2->SetMarkerStyle(20);
  gr2->SetMarkerSize(1.0);
  gr2->SetMarkerColor(1);
  gr2->SetLineWidth(2);
  gr2->SetLineColor(1);
  gr2->Draw("psameez");
 

    TLegend *leg = new TLegend(0.63,0.75,0.9,0.92);
    leg->SetFillColor(10);
    leg->SetBorderSize(0);
    leg->SetTextFont(42);
    leg->SetTextColor(1);
    leg->SetTextSize(0.04);
    //leg->SetLineStyle(0.06);
    leg->AddEntry(gr2,"Extracted v_{2}","p");
    leg->AddEntry(V2vsPt,"Input v_{2}","l");
    leg->Draw();
  
    TLatex *tex2= new TLatex(0.6,0.205,"Toy Event Generator");
    tex2->SetTextColor(1);
    tex2->SetTextSize(0.05);
    tex2->SetTextFont(42);
    tex2->Draw();


  c1->Print("eventplane_v2.png");
  c1->Print("eventplane_v2.pdf");

}