#include "Riostream.h"
#include "TAxis.h"
#include "TGaxis.h"
void dose80()

{
   ifstream in;
   in.open(Form("test1.txt"));
   Float_t px,py;

   Int_t nlines = 0;
  Int_t xmin=-10, xmax=10, Nx=1000;  // TProfile limits and number of bins, for x
  TCanvas *c1 = new TCanvas("c1","Profile histogram example",200,10,700,500);
  TProfile *h11 = new TProfile("hprof","Profile of pz versus px",Nx,xmin,xmax,0,100);

 while (1) {
      in >> px >> py;
      if (!in.good()) break;
     
 nlines++;     
 h11->Fill(px,py,1);
  }
  h11->Draw("20");
  TAxis *xaxis = h11->GetXaxis();
  Double_t x = 0, y = 0;  // x- and y-axis values
  Double_t tDose = 80;  // target dose to look for
  Double_t delta = 0.1;  // we look for tDose +- delta
  Double_t minD = tDose-delta, maxD = tDose+delta;  // interval around the desired dose
  for (Int_t i=1; i<=Nx; ++i) {
    y = h11->GetBinContent(i);
    if (y>minD && y<maxD) {
      x = xaxis->GetBinCenter(i);
 cout << x << " " << y << endl; // print x value and dose


    }
  }
}