Re: Histogram with negative bin content

Hi again,

Did you apply sumw2 to your histograms? If not the errors on subtracted histogram will be wrong and that might cause TSpectrum trouble.

-Art S.

A.E. Snyder, Group EC                        \!c*p?/
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On Tue, 5 Sep 2006, Arthur E. Snyder wrote:

> h->GetBinContents(i) <<< to check if it's negative
> h->SetBinContents(i,0) <<<< to set it to zero
>
> But are you sure you want to distort result like this? Negative bin
> content can be perfectly sensible information when you subtract
> histograms.
>
> -Art S.
>
> A.E. Snyder, Group EC \!c*p?/
> SLAC Mail Stop #95 ((. .))
> Box 4349 |
> Stanford, Ca, USA, 94309 '\|/`
> e-mail:snyder_at_slac.stanford.edu o
> phone:650-926-2701 _
> http://www.slac.stanford.edu/~snyder BaBar
> FAX:650-926-2657 Collaboration
>
>
>
> On Tue, 5 Sep 2006, Marco Calviani wrote:
>
> > Hello rooters,
> > i have a problem with a histogram: i've subtracted one histogram
> > from the other and put the result into another one. However the
> > content of some bins is negative. Is it possible in a simple way to
> > set to zero the content of negative bins?
> >
> > Thanks in advance,
> > Marco Calviani
> >
> >
>
>
Received on Tue Sep 05 2006 - 23:54:53 MEST