Re: TGraph fitting bug

Rene Brun (Rene.Brun@cern.ch)
Fri, 16 Oct 1998 19:26:34 +0200

Pavol Strizenec wrote:
>
> Dear Rooters,
>
> I would like to report small bug in fitting the graph.
> If one have the constant in the graph, and try to fit with first
> order polynomial, result is floating point exception.
> Let's try the following macro:
>
> {
> gROOT->Reset();
>
> Float_t a[5]={1,2,3,4,5};
> Float_t b[5]={0.5,0.5,0.5,0.5,0.5};
>
> TGraph *test = new TGraph(5,a,b);
>
> test->Fit("pol1");
> }
>
> with other functions (e.g. gauss) all works normaly. The same is true
> for constant histogram.
>
> I am working with Root v. 2.00/12, on Alpha/Unix with DEC/CXX compiler.
>

Thanks for reporting this simple case. Now fixed in my dev version.

Rene Brun