Re: TH2 coz & empty bins

From: Alessandro Thea <Alessandro.Thea_at_cern.ch>
Date: Thu, 10 Dec 2009 17:53:48 +0100

Thanks Olivier! That would be great.
Yes, as I understand GetBinEntries should provide the correct information. Concerning the option, as root is used in so many different contexts, I fear that somebody someday will show up asking "is it possible to PAINT the empty bins in a TProfile2D?". Such is life...

Cheers,
-a

On Dec 10, 2009, at 5:19 PM, Olivier Couet wrote:

> Hi Alessandro,
> 
> I see your point too. Yes we can may be make a special case for
> TProfile2D. I guess the test should be done on the value returned by
> GetBinEntries .. right ?  I do not think there is a need for a new
> option in a such case, as we are really sure the bin is empty. But we
> will wait after the release to test that. We cannot introduce new
> features now. The release is too close.
> 
> Cheers,  Olivier
> 
> -----Original Message-----
> From: Alessandro Thea 
> Sent: Thursday, December 10, 2009 4:59 PM
> To: Olivier Couet
> Cc: roottalk (Mailing list discussing all aspects of the ROOT system.)
> Subject: Re: [ROOT] TH2 coz & empty bins
> 
> Hello Olivier,
> thank you for you prompt answer. I see your point.
> Yet, the TProfile2D knows about the number of entries per bin.
> Maybe the option to show/hide them in the TProfile2D case should be left
> to the user.
> 
> Cheers,
> -a
> 
> 
> On Dec 10, 2009, at 4:42 PM, Olivier Couet wrote:
> 

>> Hi,
>> Yes this is how the COL option is implemented. All details are here:
>> http://root.cern.ch/root/html/THistPainter.html#HP14
>> We end up to this solution after long discussions with users. It
>> appeared it is the most reasonable one. The problem is that when you
>> have an histogram with a negative minimum there is no way to know if a
>> bin with contain 0 is really an empty which was never filled or if it

> is

>> a bin filled several times and the sum of the weights end up being 0.
>> Cheers,
>> O.Couet
>>
>>
>> -----Original Message-----
>> From: owner-roottalk_at_root.cern.ch [mailto:owner-roottalk_at_root.cern.ch]
>> On Behalf Of Alessandro Thea
>> Sent: Thursday, December 10, 2009 4:33 PM
>> To: roottalk (Mailing list discussing all aspects of the ROOT system.)
>> Subject: [ROOT] TH2 coz & empty bins
>>
>> Hello rooters,
>> We are having a problem dealing with a THProfile2D drawn with the

> "col"

>> option.
>> I fear this might have been already discussed in the past, forgive me

> if

>> I'm reopening the discussion.
>> The TProfile2D we use is filled incrementally and allows both positive
>> and negative values. When displayed it is plotted in color ("COL").
>> Now, the trouble is the THistPainter paints the empty bins if zmin <

> 0,

>> doesn't paint them if otherwise.
>>
>> For us is important to distinguish between empty bins and bins which
>> value is 0 or close to 0.
>> Isn't there a way to force the empty bins to be hidden? I have found

> it

>> for the lego plot ("0" option) but not for the other drawing modes.
>>
>> Thank you in advance for any help.
>> Alessandro
>>
>>

> ________________________________________________________________________

>> __
>>
>> ETH Zurich
>> Dr. Alessandro Thea
>> Institute for Particle Physics
>>
>> CERN, European Laboratory for Particle Physics,
>> CH-1211, Geneve 23, Switzerland,
>> PH/UCM, Office 32-2-B03, Mailbox: F17500
>>
>> Tel: +41-76-487-1800 E-Mail: Alessandro.Thea_at_cern.ch
>>

> ________________________________________________________________________

>> __
>>

> 
> ________________________________________________________________________
> __
> 
>  ETH Zurich
>  Dr. Alessandro Thea
>  Institute for Particle Physics
> 
>  CERN, European Laboratory for Particle Physics,
>  CH-1211, Geneve 23, Switzerland,
>  PH/UCM, Office 32-2-B03, Mailbox: F17500
> 
>  Tel: +41-76-487-1800               E-Mail: Alessandro.Thea_at_cern.ch
> ________________________________________________________________________
> __
> 

__________________________________________________________________________

  ETH Zurich
  Dr. Alessandro Thea
  Institute for Particle Physics

  CERN, European Laboratory for Particle Physics,   CH-1211, Geneve 23, Switzerland,
  PH/UCM, Office 32-2-B03, Mailbox: F17500

  Tel: +41-76-487-1800 E-Mail: Alessandro.Thea_at_cern.ch

---

Received on Thu Dec 10 2009 - 17:53:54 CET