#include "iostream.h"
#include "TObject.h"
#include "TString.h"
#include "TTree.h"
#include "TFile.h"
#include "TTree.h"
#include "TGraph.h"
#include "TGraphErrors.h"
#include "TLatex.h"
void Superimpose_rates(){
   //
   // Example showing how to superimpose a TGraph with a different range
   // using a transparent pad.
   //
   gROOT->Reset();
   c1 = new TCanvas("c1","EffGain_Rates",200,10,700,500);
   TPad *pad = new TPad("pad","",0,0,1,1);
   pad->SetGrid();
   pad->Draw();
   pad->cd();
   
      // create first graph
   gr1 = new TGraphErrors("Gain2800_1700_1400_300_500.txt");
   //gr1->SetTitle("2800_1700_1400_300_500");
   gr1->SetMarkerColor(kBlue);
   gr1->SetMarkerStyle(21);
   gr1->GetYaxis()->SetLabelColor(kBlue);
   gr1->GetYaxis()->SetTitle("Effective Gain");
  // gr1->GetYaxis()->SetTitlelColor(kBlue);
   gr1->GetYaxis()->SetTitleOffset(1.5); //Set YTitle Offset 20% more than the standard one
   gr1->Draw("AP");

      // create second graph
   //create a transparent pad drawn on top of the main pad
   c1->cd();
   TPad *overlay = new TPad("overlay","",0,0,1,1);
     //compute the pad range with suitable margins
   Double_t ymin = 0;
   Double_t ymax = 2000;
   Double_t dy = (ymax-ymin)/0.8; //10 per cent margins top and bottom
   Double_t xmin = -3;
   Double_t xmax = 3;
   Double_t dx = (xmax-xmin)/0.8; //10 per cent margins left and right
   overlay->Range(xmin-0.1*dx,ymin-0.1*dy,xmax+0.1*dx,ymax+0.1*dy);
   overlay->SetFillStyle(4000);// will be transparent
   overlay->SetFillColor(0);
   overlay->SetFrameFillStyle(4000);
   overlay->Draw();
   overlay->cd();
   gr2 = new TGraphErrors("Rates2800_1700_1400_300_500.txt");
   gr2->GetYaxis()->SetLabelOffset(999);
   gr2->GetYaxis()->SetTickLength(0);
   gr2->GetXaxis()->SetTitle("Drift Voltage [V]");
   gr2->GetXaxis()->CenterTitle();
   gr2->SetMarkerColor(kRed);
   gr2->SetMarkerStyle(20);
   gr2->SetName("gr2");
	gr2->Draw("AP");
   overlay->Update();
  
  // Draw an axis on the right side
  TGaxis *axis = new TGaxis(2740,ymin,2740, ymax,ymin,ymax,51010,"+S",0.03);
	axis->SetLabelOffset(0.05);
	axis->SetLineColor(kRed);
	axis->SetLabelColor(kRed);
	axis->SetTickLength(0.01);
	axis->SetLabelSize(0.03);
	axis->SetTitle("Rates [Hz]");
  axis->Draw();

}