void gausfit( TH1F *histname,   
	      Double_t &sigma,       Double_t &errsigma,
	      Double_t &chisq,       Double_t &ndf)
{

  histname->Fit("gaus");
  TF1 *gausfunc = histname->GetFunction("gaus");

  Double_t chisq     = gausfunc->GetChisquare();
  Double_t ndf       = gausfunc->GetNDF();if(ndf == 0)ndf=-999;
  Double_t sigma     = gausfunc->GetParameter(2); 
  Double_t errsigma = gausfunc->GetParError(2);
}