Re: root : unbinned fit 1D

Hi,
On Dec 6, 2009, at 1:02 AM, Arthur E. Snyder wrote:

> Hello Marc,
>
> An unbinned fit to a histogram makes no sense. Presumably you mean you want to fit the data that is used to make the histogram w/o binning it.
>
> I'm not sure if ROOT has a native unbinned fitter; you could use RooFit or you could write your own using minuit via TMinuit.

you can do an unbinned fit in ROOT on a TTree. See TTree::UnbinnedFit (http://root.cern.ch/root/htmldoc/TTree.html#TTree:UnbinnedFit )

Lorenzo

>
> A likelihood fit to a finely binned histogram is more or less equivalent to an unbinned fit and ROOT does do that.
>
> -Art S.
>
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>
> On Sun, 6 Dec 2009, Marc Escalier wrote:
>

>> Dear root experts,
>> 
>> would somebody know how to proceed to do a unbinned fit of a TH1 histo ?
>> 
>> for example, lets consider
>> MyTH1Histo->Fit("gaus")
>> 
>> ==>i wish to do this fit, but with a unbinned fit
>> 
>> thank you
>> 
>> (i will thank those who know in private to prevent spamming people)
>> 
>>