// 
// Root macro to linearly transform the y axis of a 1D histogram
// such that the minimum and maximum contents are the requested values.
//

TH1D *rescale(const TH1D *hist, Double_t newmin=0, Double_t newmax=1)
{
   TString hname = hist->GetName();
   TH1D *hres = hist->Clone(hname + "_rescaled");
   Double_t oldmin = hres->GetBinContent(hres->GetMinimumBin());
   Double_t oldmax = hres->GetBinContent(hres->GetMaximumBin());
   Int_t nbins = hres->GetXaxis()->GetNbins();
   for (Int_t bin=1; bin <= nbins; ++bin) {
      Double_t y = hres->GetBinContent(bin);
      y = (y-oldmin)*(newmax-newmin)/(oldmax-oldmin)+newmin;
      hres->SetBinContent(bin,y);
   }
   return hres;
}