[ROOT] About fit with my function

From: babintsev@mx.ihep.su
Date: Sat Feb 17 2001 - 15:19:20 MET 

      babintsev@mx.ihep.su, 17-FEB-2001

Hello rooters.

What does it mean: I take script from tutorials (below):
and have the following result (Root  Version   2.25/03)

root [1] .x fitexample.C

 *** Break *** floating point exception
Root > Function fitf() busy flag cleared
Function fitexample() busy flag cleared


   //_____________________macro fitexample.C___________________________
   Double_t fitf(Double_t *x, Double_t *par)
   {
      Double_t arg = 0;
      if (par[2]) arg = (x[0] - par[1])/par[2];

      Double_t fitval = par[0]*TMath::Exp(-0.5*arg*arg);
      return fitval;
   }
   void fitexample()
   {
      TFile *f = new TFile("hsimple.root");

      TH1F *hpx = (TH1F*)f->Get("hpx");

      TF1 *func = new TF1("fit",fitf,-3,3,3);
      func->SetParameters(500,hpx->GetMean(),hpx->GetRMS());
      func->SetParNames("Constant","Mean_value","Sigma");
      hpx->Fit("fit");
   }
-------end of script---------------------

Thanks a lot.

                                   Volodja Babintsev

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