float dat1(int i, int k) {

  float dd[9][4] = {
       0.5000000,     0.2032801, 0.,    0.0074016,
       1.5000000,     0.1750048, 0.,    0.0041545,
       2.5000000,     0.1257404, 0.,    0.0076406,
       3.5000000,     0.0683140, 0.,    0.0110888,
       4.5000000,     0.1049370, 0.,    0.0266719,
       5.5000000,     0.0310185, 0.,    0.0185445,
       6.5000000,     0.0227041, 0.,    0.0102301,
       7.5000000,     0.0244048, 0.,    0.0119308,
       8.5000000,     0.0375000, 0.,    0.0250260	 
  };

  return dd[i][k];
}

float dat2(int i, int k) {

  float dd[6][4] = {
       0.5000000,     0.2233434, 0,     0.0317605,
       1.5000000,     0.1638513, 0,     0.0186609,
       2.5000000,     0.0956099, 0,     0.0143173,
       3.5000000,     0.0676181, 0,     0.0117128,
       4.5000000,     0.0508562, 0,     0.0100735,
       5.5000000,     0.0220012, 0,     0.0047466
  };

  return dd[i][k];
}

int mbias_zeros_vs_p() {
   gROOT->Reset();
   c1 = new TCanvas("mbias_zeros_vs_p","mbias_zeros_vs_p",0,0,600,400);

				// create a 2D histogram to define the range

   TH2F *hr = new TH2F("hr","Fraction of \"zeros\" vs momentum",
		       1,0.,12.,1,0,0.3);

   hr->SetXTitle("P, GeV/c");
   hr->Draw();

   c1->GetFrame()->SetFillColor(21);
   c1->GetFrame()->SetBorderSize(12);

   float x[1000], y[1000], ex[1000], ey[1000];

					// create first graph
   int n1 = 9;
   for (int i=0; i<n1; i++) {
     x [i] = dat1(i,0);
     y [i] = dat1(i,1);
     ex[i] = dat1(i,2);
     ey[i] = dat1(i,3);
   }

   gr1 = new TGraphErrors(n1,x,y,ex,ey);
   gr1->SetMarkerColor(kBlue);
   gr1->SetMarkerStyle(21);
   gr1->Draw("LP");

   TText* text = new TText(4.,0.25,"QFL: red circles");
   text->Draw();     

   int n2 = 6;
   for (int i=0; i<n2; i++) {
     x [i] = dat2(i,0);
     y [i] = dat2(i,1);
     ex[i] = dat2(i,2);
     ey[i] = dat2(i,3);
   }

   gr2 = new TGraphErrors(n2,x,y,ex,ey);
   gr2->SetMarkerColor(kRed);
   gr2->SetMarkerStyle(20);
   gr2->Draw("LP");

   TText* text = new TText(4.,0.22,"Minbias: blue squares");
   text->Draw();     
}