void v2red() {

  TFile *v2all = TFile::Open("v2all.root","RECREATE");
  v2all->cd();

  //centrality1
  TCanvas *c1 = new TCanvas();
  auto centrality1 = new TMultiGraph();

  TGraphErrors *gr1 = new TGraphErrors("~/macros/v2pions1.txt", "%lg %*s %*s %lg %lg");
  gr1->SetLineColor(kBlue);
  centrality1->Add(gr1);

  TGraphErrors *gr2 = new TGraphErrors("~/macros/v2kaons1.txt", "%lg %*s %*s %lg %lg");
  gr2->SetLineColor(kRed);
  centrality1->Add(gr2);

  TGraphErrors *gr3 = new TGraphErrors("~/macros/v2protons1.txt", "%lg %*s %*s %lg %lg");
  gr3->SetLineColor(kBlack);
  centrality1->Add(gr3);

  centrality1->Draw("AL");
  centrality1->SetTitle("v2 vs P_{t} for centrality 0-1%");
  centrality1->GetXaxis()->SetTitle("P_{t}");
  centrality1->GetYaxis()->SetTitle("v2");
  centrality1->Write("0To1");

  TLegend *leg1 = new TLegend();
  leg1->SetFillColor(0);
  leg1->AddEntry(gr1,"pions","L");
  leg1->AddEntry(gr2, "kaons","L");
  leg1->AddEntry(gr3, "protons","L");
  //leg1->Write("leg1");
  leg1->Draw();

   

  //centrality5
  TCanvas *c2 = new TCanvas();
  auto centrality5 = new TMultiGraph();

  TGraphErrors *gr4 = new TGraphErrors("~/macros/v2pions1.txt", "%lg %*s %*s %lg %lg");
  gr4->SetLineColor(kBlue);
  centrality5->Add(gr4);

  TGraphErrors *gr5 = new TGraphErrors("~/macros/v2kaons1.txt", "%lg %*s %*s %lg %lg");
  gr5->SetLineColor(kRed);
  centrality5->Add(gr5);

  TGraphErrors *gr6 = new TGraphErrors("~/macros/v2protons1.txt", "%lg %*s %*s %lg %lg");
  gr6->SetLineColor(kBlack);
  centrality5->Add(gr6);

  centrality5->Draw("AL");
  centrality5->SetTitle("v2 vs P_{t} for centrality 0-5%");
  centrality5->GetXaxis()->SetTitle("P_{t}");
  centrality5->GetYaxis()->SetTitle("v2");
  centrality5->Write("0To5");

  TLegend *leg2 = new TLegend();
  leg2->SetFillColor(0);
  leg2->AddEntry(gr4,"pions","L");
  leg2->AddEntry(gr5, "kaons","L");
  leg2->AddEntry(gr6, "protons","L");
  //leg2->Write("leg2");
  leg2->Draw();

  //centrality10
  TCanvas *c3 = new TCanvas();
  auto centrality10 = new TMultiGraph();

  TGraphErrors *gr7 = new TGraphErrors("~/macros/v2pions1.txt", "%lg %*s %*s %lg %lg");
  gr7->SetLineColor(kBlue);
  centrality10->Add(gr7);

  TGraphErrors *gr8 = new TGraphErrors("~/macros/v2kaons1.txt", "%lg %*s %*s %lg %lg");
  gr8->SetLineColor(kRed);
  centrality10->Add(gr8);

  TGraphErrors *gr9 = new TGraphErrors("~/macros/v2protons1.txt", "%lg %*s %*s %lg %lg");
  gr9->SetLineColor(kBlack);
  centrality10->Add(gr9);

  centrality10->Draw("AL");
  centrality10->SetTitle("v2 vs P_{t} for centrality 5-10%");
  centrality10->GetXaxis()->SetTitle("P_{t}");
  centrality10->GetYaxis()->SetTitle("v2");
  centrality10->Write("5To10");

  TLegend *leg3 = new TLegend();
  leg3->SetFillColor(0);
  leg3->AddEntry(gr7,"pions","L");
  leg3->AddEntry(gr8, "kaons","L");
  leg3->AddEntry(gr9, "protons","L");
  leg3->Write("leg3");
  leg3->Draw();

  //centrality20
  TCanvas *c4 = new TCanvas();https://root.cern.ch/howtos
  auto centrality20 = new TMultiGraph();

  TGraphErrors *gr10 = new TGraphErrors("~/macros/v2pions1.txt", "%lg %*s %*s %lg %lg");
  gr10->SetLineColor(kBlue);
  centrality20->Add(gr10);

  TGraphErrors *gr11 = new TGraphErrors("~/macros/v2kaons1.txt", "%lg %*s %*s %lg %lg");
  gr11->SetLineColor(kRed);
  centrality20->Add(gr11);

  TGraphErrors *gr12 = new TGraphErrors("~/macros/v2protons1.txt", "%lg %*s %*s %lg %lg");
  gr12->SetLineColor(kBlack);
  centrality20->Add(gr12);

  centrality20->Draw("AL");
  centrality20->SetTitle("v2 vs P_{t} for centrality 10-20%");
  centrality20->GetXaxis()->SetTitle("P_{t}");
  centrality20->GetYaxis()->SetTitle("v2");
  centrality20->Write("10To20");

  TLegend *leg4 = new TLegend();
  leg4->SetFillColor(0);
  leg4->AddEntry(gr10,"pions","L");
  leg4->AddEntry(gr11, "kaons","L");
  leg4->AddEntry(gr12, "protons","L");
  //leg4->Write("leg4");
  leg4->Draw();

  //centrality30
  TCanvas *c5 = new TCanvas();
  auto centrality30 = new TMultiGraph();

  TGraphErrors *gr13 = new TGraphErrors("~/macros/v2pions1.txt", "%lg %*s %*s %lg %lg");
  gr13->SetLineColor(kBlue);
  centrality30->Add(gr13);

  TGraphErrors *gr14 = new TGraphErrors("~/macros/v2kaons1.txt", "%lg %*s %*s %lg %lg");
  gr14->SetLineColor(kRed);
  centrality30->Add(gr14);

  TGraphErrors *gr15 = new TGraphErrors("~/macros/v2protons1.txt", "%lg %*s %*s %lg %lg");
  gr15->SetLineColor(kBlack);
  centrality30->Add(gr15);

  centrality30->Draw("AL");
  centrality30->SetTitle("v2 vs P_{t} for centrality 20-30%");
  centrality30->GetXaxis()->SetTitle("P_{t}");
  centrality30->GetYaxis()->SetTitle("v2");
  centrality30->Write("20To30");
  
  TLegend *leg5 = new TLegend();
  leg5->SetFillColor(0);
  leg5->AddEntry(gr13,"pions","L");
  leg5->AddEntry(gr14, "kaons","L");
  leg5->AddEntry(gr15, "protons","L");
  // leg5->Write("leg5");
  leg5->Draw();

  //centrality40
  TCanvas *c6 = new TCanvas();
  auto centrality40 = new TMultiGraph();

  TGraphErrors *gr16 = new TGraphErrors("~/macros/v2pions1.txt", "%lg %*s %*s %lg %lg");
  gr16->SetLineColor(kBlue);
  centrality40->Add(gr16);

  TGraphErrors *gr17 = new TGraphErrors("~/macros/v2kaons1.txt", "%lg %*s %*s %lg %lg");
  gr17->SetLineColor(kRed);
  centrality40->Add(gr17);

  TGraphErrors *gr18 = new TGraphErrors("~/macros/v2protons1.txt", "%lg %*s %*s %lg %lg");
  gr18->SetLineColor(kBlack);
  centrality40->Add(gr18);

  centrality40->Draw("AL");
  centrality40->SetTitle("v2 vs P_{t} for centrality 30-40%");
  centrality40->GetXaxis()->SetTitle("P_{t}");
  centrality40->GetYaxis()->SetTitle("v2");
  centrality40->Write("30To40");

  TLegend *leg6 = new TLegend();
  leg6->SetFillColor(0);
  leg6->AddEntry(gr16,"pions","L");
  leg6->AddEntry(gr17, "kaons","L");
  leg6->AddEntry(gr18, "protons","L");
  //leg6->Write("leg6");
  leg6->Draw();

  //centrality50
  TCanvas *c7 = new TCanvas();
  auto centrality50 = new TMultiGraph();

  TGraphErrors *gr19 = new TGraphErrors("~/macros/v2pions1.txt", "%lg %*s %*s %lg %lg");
  gr19->SetLineColor(kBlue);
  centrality50->Add(gr19);

  TGraphErrors *gr20 = new TGraphErrors("~/macros/v2kaons1.txt", "%lg %*s %*s %lg %lg");
  gr20->SetLineColor(kRed);
  centrality50->Add(gr20);

  TGraphErrors *gr21 = new TGraphErrors("~/macros/v2protons1.txt", "%lg %*s %*s %lg %lg");
  gr21->SetLineColor(kBlack);
  centrality50->Add(gr21);

  centrality50->Draw("AL");
  centrality50->SetTitle("v2 vs P_{t} for centrality 40-50%");
  centrality50->GetXaxis()->SetTitle("P_{t}");
  centrality50->GetYaxis()->SetTitle("v2");
  centrality50->Write("40To50");

  TLegend *leg7 = new TLegend();
  leg7->SetFillColor(0);
  leg7->AddEntry(gr19,"pions","L");
  leg7->AddEntry(gr20, "kaons","L");
  leg7->AddEntry(gr21, "protons","L");
  //leg7->Write("leg7");
  leg7->Draw();  

  v2all->Close();
  
}