Re: Histogram mean

From: Arthur E. Snyder <snyder_at_slac.stanford.edu>
Date: Tue, 13 Sep 2011 12:50:31 -0700


Aamer,

It doesn't work on subtracted histograms. I had to 'roll-my-own' to do that (though there might be something existing that does this that I just didn't find).

As I recall |root] does unbinned mean, so you get the same result regardless of binning. It's not clear what it does the case of subtracted histograms, but if the histograms is asymmetric the result can be wildly wrong.

-Art S.

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On Tue, 13 Sep 2011, Aamer Wali Rauf wrote:

> Hi,
> I have always assumed (and thus used) that the TH1::GetMean(1) method gives out the weighted mean value
> of the x-axis of the histogram. Visibly it looks to me that way but is it really so? Can someone
> comment on that please?
>
> Thanks in advance,
> Aamer 
>
>
Received on Tue Sep 13 2011 - 21:50:42 CEST

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