Double_t inclusivePtFitter40NewErr(Double_t *x, Double_t *par)
{
  if (x[0] < 0.4)
    {
      TF1::RejectPoint();
      return 0.;
    }
  Double_t result = par[0] + par[1] * TMath::Exp(par[2] * x[0]) + 1. / (par[3] + par[4] * x[0]) + x[0] / (par[5] + par[6] * x[0]);
  if (result > 0.)
    {
      return result;
    } else
      {
	return 0.;
      }
}



void Chi2Test()
{
  // Get histo from file
  TFile *outFile = new TFile("Chi2Test.root");
  outFile->cd();
  TH1D *histToFit = (TH1D *)gROOT->FindObject("MCK0sRecFoundsInclusivePt40RebinNewErr");

  // Draw histo
  TCanvas *chi2Canvas = new TCanvas("canv", "Canvas", 0, 0, 1800, 1000);
  chi2Canvas->Divide(2, 1);
  chi2Canvas->cd(1);
  chi2Canvas->cd(1)->SetLogy();
  histToFit->Draw();
  // Fit
  TF1 *inclusivePtFit40NewErr = new TF1("InclusivePtFit40NewErr", inclusivePtFitter40NewErr, .4, 20., 7);
  inclusivePtFit40NewErr->SetParameters(1., 70., -1., .1, .1, .1, .1);
  inclusivePtFit40NewErr->SetLineColor(4);
  histToFit->Fit("InclusivePtFit40NewErr", "0", "", 0.45, 17.);
  inclusivePtFit40NewErr->Draw("SAME");

  // Contour
  chi2Canvas->cd(2);
  gMinuit->SetErrorDef(4);
  TGraph *chi2PlotMc2 = (TGraph *)gMinuit->Contour(80, 0, 1);
  chi2PlotMc2->SetFillColor(42);
  chi2PlotMc2->Draw("alf");
//   gMinuit->SetErrorDef(1);
//   TGraph *chi2PlotMc1 = (TGraph *)gMinuit->Contour(80, 0, 1);
//   chi2PlotMc1->SetFillColor(38);
//   chi2PlotMc1->Draw("lf");
  
  return;
}