Re: TProfile nan bins.

From: Stefan Piperov <piperov_at_fnal.gov>
Date: Fri, 11 Mar 2011 11:26:32 +0200

Well, the initial user complaint, that two statistical entities, treated in a similar, statistically valid, way produce inconsistent result remains unaddressed.
Other users will fall in the same trap as BetterWang did if this behaviour remains as it is.

Perhaps ROOT can be more coherent here?
Stefan.

On Fri, 11 Mar 2011, Lorenzo Moneta wrote:

> Hi,
>
> If you fill a NaN in an histogram, it will go to the overflow bin, while if the y value of the Profile is a NaN
> the resulting bin content will be NaN. This has the advantage that can be immediately discovered by the user.
> I think it is a user responsibility not to fill histogram or profile with NaN values
>
> Best Regards
>
> Lorenzo
> On Mar 11, 2011, at 5:27 AM, BetterWang wrote:
>
>> Well, it has been solved.
>> In very rare occasions, I have NaN from divided by zero.
>> If I fill NaN in a 2D histo, I won't have problem at all.
>> But if I fill NaN in a TProfile, it will result that bin to be NaN.
>> Maybe TProfile can have NaN protection in the Fill function, or leave
>> that to users.
>>
>> Thanks,
>>
>>
>> On Wed, Mar 9, 2011 at 3:19 AM, Lorenzo Moneta <Lorenzo.Moneta_at_cern.ch> wrote:
>>> Hi,
>>>
>>> Can you please send me a macro reproducing this problem ?
>>> Thank you
>>>
>>> Lorenzo
>>> On Mar 1, 2011, at 5:07 PM, BetterWang wrote:
>>>
>>>> Hi ROOT experts,
>>>>
>>>> I am filling TH2D and TProfile at the same time.
>>>> They have the same definition, for example:
>>>>
>>>> TH2D *h2 = new TH2D("h2", h2", 220, -1.1, 1.1, 220, -1.1, 1.1);
>>>> TProfile *h2p = new TProfile("h2p", "h2p", 220, -1.1, 1.1, -1.1, 1.1);
>>>>
>>>> After filling lots of data.
>>>> h2 looks fine, but h2p has some bins with content "NaN".
>>>> h2->ProfileX() can give a profile without any problem.
>>>> Does anyone know what is going on under the hood?
>>>> And how can I avoid "NaN" in a TProfile?
>>>>
>>>> Thanks,
>>>>
>>>
>>>
>
>

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  Stefan Piperov      Mail: FNAL P.O.Box 500, MS 205, Batavia, IL-60510
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"Give a skeptic an inch... and he'll measure it." Received on Fri Mar 11 2011 - 10:26:40 CET