{

#include <TH1F.h>
#include <TH2F.h>
#include <THStack.h>
#include <TLegend.h>
#include <TFile.h>
#include <TMath.h>
#include <TLine.h>
#include <TGraphAsymmErrors.h>
#include <TCanvas.h>
#include <vector>

using namespace std;

 TCanvas* Canvas = new TCanvas ("Canvas","Canvas",10,10,700,500); 
 
 Canvas.cd();

 h_ratio_b = new TGraphAsymmErrors();
 for(int i=1; i<=5; i++){
   Double_t EH1 = -99;
   Double_t EL1 = -99;
   Double_t EH2 = -99;
   Double_t EL2 = -99;
   Double_t valuefinal = 0;
   Double_t DN = 0;
   Double_t MCN = 0;
   EH1 = 15;
   EL1 = 1;
   EH2 = 3;
   EL2 = 1.01;
   DN = 10;
   MCN = 1;
   valuefinal = DN/MCN;
   Double_t error_poisson_up = 0;
   Double_t error_poisson_down = 0; 
   if(valuefinal!=0) { 
     error_poisson_up = (sqrt( pow((EH1/DN),2) + pow((EH2/MCN),2) ))*(DN/MCN);
     error_poisson_down = (sqrt( pow((EL1/DN),2) + pow((EL2/MCN),2) ))*(DN/MCN);
     h_ratio_b->SetPoint(i-1, i, valuefinal);
     h_ratio_b->SetPointError(i-1, 0, 0, error_poisson_down, error_poisson_up);
   }
 }

 h_ratio_b->SetMaximum(45);
 //h_ratio_b->SetMaximum(2);
 h_ratio_b->SetMinimum(0);
 h_ratio_b.Draw("AP0");
 TF1 *Line = new TF1("Line","1",70,2000);
 Line->SetLineWidth(0.5);
 Line->SetLineColor(2);
 Line->Draw("sameL");
 h_ratio_b->Draw("AP0same");

}