Re: Problem drawing 2D histograms with all entries at zero with colz option

On Wed, Jul 6, 2011 at 1:09 PM, Melinda Siciliano <mellybinda_at_gmail.com>wrote:

> Hi Olivier,
>
> In the example I forced a little bit the effect. But, I think that the
> problem is general: if I have a macro in which I want to analyze some data
> and I have an histogram that I fill and it could happen that this histo can
> be filled with zero. But at this point, I expect that the histogram will be
> plot "empty" with the entries with zero value and I see that the result of
> the macro is this histogram have all the entries to zero.I think it is a
> general case that I expect a flat distribution with a value like zero
> instead of a number different to zero. With the previous versions, there
> wasn't this problem, but it appears with the 5-28-00*. I think that Annalisa
> can give us some more details about the histogram and how it is filled.
>
> Cheers,
>
> Melinda
>
>
>
> On Wed, Jul 6, 2011 at 12:05 PM, Olivier Couet <Olivier.Couet_at_cern.ch>wrote:
>
>> Hi,
>>
>> You Paint using COLZ. So an axis will be painted along the palette.
>> But the histogram is empty therefore this axis ends and starts at 0.
>> That's what the message says.
>> Nothing has changed.
>> You used the option Z in the past also ? Your histograms were also empty ?
>>
>> Cheers
>>
>> From: Melinda Siciliano <mellybinda_at_gmail.com>
>> Date: Wed, 6 Jul 2011 11:49:21 +0200
>> To: "roottalk (Mailing list discussing all aspects of the ROOT system.)"
>> <roottalk_at_cern.ch>
>> Cc: Annalisa Mastroserio <Annalisa.Mastroserio_at_cern.ch>, Chiara Bianchin
>> <Chiara.Bianchin_at_cern.ch>, Domenico Elia <Domenico.Elia_at_cern.ch>, Massimo
>> Masera <masera_at_to.infn.it>
>> Subject: [ROOT] Problem drawing 2D histograms with all entries at zero
>> with colz option
>>
>> Dear ROOTers,
>>
>> I'm using the ROOT v5-28-00e. I have a situation similar to the one in the
>> attached file. I have a 2D histogram that is filled with the number returned
>> from another object. If the object is OK, this object returns 0, otherwise,
>> in case of error, it will return a number different from zero, according
>> with an error table. In principle. So, if my histogram is ok , all my
>> entries will be set to zero.
>>
>> With the past releases I didn't get any error, but now I receive a
>> floating point error and the message
>>
>> Error in <TGaxis::PaintAxis>: wmin (0.000000) == wmax (0.000000).
>>
>> Has something changed between the previous release (v5-27-06)? What have
>> I to modify?
>>
>> Thanks for your help,
>>
>> Cheers,
>>
>> Melinda
>>
>>
>>
>
Received on Wed Jul 06 2011 - 13:18:52 CEST