#include "TFile.h"
#include "TCanvas.h"
#include "TStyle.h"
#include "TH1.h"
#include "TH2.h"
#include "TH3.h"
#include "TGaxis.h"
#include "TRandom.h"
#include "TLegend.h"
#include "TPaveStats.h"
#include "TGraph.h"

void hfirstint()
{

   
   TFile *g = TFile::Open("G:/cors/gamma/gammatot/cors_plot-gammatot.root");
   if (g == 0) {
      // if we cannot open the file, print an error message and return immediatly
      printf("Error: cannot open cors_plot.root!\n");
      return;
   }
   g->ls();
    TFile *p = TFile::Open("G:/cors/prot/prottot/cors_plot-prottot.root");
   if (p == 0) {
      // if we cannot open the file, print an error message and return immediatly
      printf("Error: cannot open cors_plot.root!\n");
      return;
   }
   p->ls();
    TH1F *hfirstintg = (TH1F *)g->Get("hfirstint");
   if (hene == 0) {
      printf("Error getting an histogram from the file!\n");
      return;
   }
   TH1F *hfirstintp = (TH1F *)p->Get("hfirstint");
   if (hene == 0) {
      printf("Error getting an histogram from the file!\n");
      return;
   }
   float offx=1.2;
   float offy=1;
   float marg=0.15;
   TCanvas *c2 = new TCanvas("c2","hists with different scales",1280,1024);
   TPad *pad1 = new TPad("pad1", "pad1", 0, 0.3, 1, 1.0);
   pad1->SetBottomMargin(0); // Upper and lower plot are joined
   pad1->SetGridx();         // Vertical grid
   pad1->Draw();             // Draw the upper pad: pad1
   pad1->cd();               // pad1 becomes the current pad
   // hfirstintg->SetStats(0);          // No statistics on upper plot
   //c2->SetLogx();
   //c2->SetLogy();
   //hfirstintg->SetMaximum(5.5e4);
   hfirstintg->SetLineColor(kBlack);
   hfirstintg->SetTitle("Quota di prima interazione dei #gamma e #font[12]{p} primari");
   hfirstintg.GetXaxis()->SetTitle("Altezza (Km)");
   hfirstintg.GetYaxis()->SetTitle("N_{part}");
   hfirstintg->GetYaxis()->SetTitleOffset(offy);
   c2->SetLeftMargin(marg);
   hfirstintg->Draw();
   c2->Update();
   hfirstintp->SetLineColor(kBlue);
   hfirstintp->Draw("sames");
   // Do not draw the Y axis label on the upper plot and redraw a small
   // axis instead, in order to avoid the first label (0) to be clipped.
   hfirstintg->GetYaxis()->SetLabelSize(0.);
   TGaxis *axis = new TGaxis( -5, 20, -5, 220, 20,220,510,"");
   axis->SetLabelFont(43); // Absolute font size in pixel (precision 3)
   axis->SetLabelSize(15);
   axis->Draw();
   c2->Update();
  c2->cd();          // Go back to the main canvas before defining pad2
   TPad *pad2 = new TPad("pad2", "pad2", 0, 0.05, 1, 0.3);
   pad2->SetTopMargin(0);
   pad2->SetBottomMargin(0.2);
   pad2->SetGridx(); // vertical grid
   pad2->Draw();
   pad2->cd();       // pad2 becomes the current pad
   c2->Update();
    // Define the ratio plot
    TLegend* leg = new TLegend(0.6, 0.7, .4, .80);
   leg->SetNColumns(1);
   leg->AddEntry(hfirstintg, "#gamma", "l");
   leg->AddEntry(hfirstintp, "#font[12]{p}", "l");
   leg->Draw("same");
   TPaveStats *stats1 = (TPaveStats*)hfirstintg->GetListOfFunctions()->FindObject("stats");
   TPaveStats *stats2 = (TPaveStats*)hfirstintp->GetListOfFunctions()->FindObject("stats");
   stats1->SetTextColor(kBlack);
   stats2->SetTextColor(kBlue);
   stats1->SetX1NDC(0.80); stats1->SetX2NDC(0.98);
   stats1->SetY1NDC(0.79); stats1->SetY2NDC(0.94);
   stats2->SetX1NDC(0.80); stats2->SetX2NDC(0.98);
   stats2->SetY1NDC(0.62); stats2->SetY2NDC(0.77);
   c2->Update();
   TH1F *h3 = (TH1F*)hfirstintg->Clone("h3");
   h3->SetLineColor(kBlack);
    h3->SetMinimum(0);  // Define Y ..
   h3->SetMaximum(15.); // .. range
   h3->Sumw2();
   h3->SetStats(0);      // No statistics on lower plot
   h3->Divide(hfirstintp);
   h3->SetMarkerStyle(21);
   h3->Draw("ep");       // Draw the ratio plot
   
    // Ratio plot (h3) settings
   h3->SetTitle(""); // Remove the ratio title

   // Y axis ratio plot settings
   h3->GetYaxis()->SetTitle("h_{#gamma}/h_{p} ");
   h3->GetYaxis()->SetNdivisions(505);
   h3->GetYaxis()->SetTitleSize(20);
   h3->GetYaxis()->SetTitleFont(43);
   h3->GetYaxis()->SetTitleOffset(1.55);
   h3->GetYaxis()->SetLabelFont(43); // Absolute font size in pixel (precision 3)
   h3->GetYaxis()->SetLabelSize(15);

   // X axis ratio plot settings
   h3->GetXaxis()->SetTitleSize(20);
   h3->GetXaxis()->SetTitleFont(43);
   h3->GetXaxis()->SetTitleOffset(4.);
   h3->GetXaxis()->SetLabelFont(43); // Absolute font size in pixel (precision 3)
   h3->GetXaxis()->SetLabelSize(15);
   gROOT->ProcessLine("gROOT->SetBatch()");
   c2.Print("G:/cors/gamma/gammaeprot_tot_firstint.pdf"); delete c2;
   gROOT->ProcessLine("gROOT->SetBatch(kFALSE)");
   


   
}