Re: Strange crash making draw in a macro

I don't think that is the case, but I'll double check ..

-Thanks

A.E. Snyder, The Former Group C (TFC)        \!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:707-313-0250                          Collaboration
                                                 &
                                            Fermi/GLAST

On Fri, 30 Mar 2012, Philippe Canal wrote:

>
> >Error in <TSelectorDraw::Begin>: An object of type 'TH1D' has the same name as the requested event list (hVar671)
> >(class TH1D*)0x947be20
>
> This would happen if the value of 'yyvar' is an empty string.
> This would mean that:
> tup->Draw(">>hVar671",cut);
> is being executed ... this explicitly request the create an event list with the name hVar671 which interfers somehow
> with the histogram of the same name.
>
> Cheers,
> Philippe.
>
>
> On 3/30/12 4:05 PM, Arthur E. Snyder wrote:
>> ROOT 5.26/00a (tags/v5-26-00a_at_32053, Jan 19 2010, 12:43:52 on linux)
>>
>> CINT/ROOT C/C++ Interpreter version 5.17.00, Dec 21, 2008
>>
>>
>> In executing the following simple minded macro:
>>
>> TH1D* hDo=0;
>> TString hDoName="";
>> TH1D* doDraw(TTree* tup) {
>> sAndB(0);
>> hDoName="hVar";
>> hDoName+=getTagI();
>>
>>
>> cout << "hDoName:" << hDoName << endl;
>> hDo=new TH1D(hDoName,yyvar,nyy,yylo,yyup);
>> cout << "hDo:" << hDo << endl;
>>
>> if(tup->GetTitle()=="front") hDo->SetLineColor(2);
>> if(tup->GetTitle()=="back") hDo->SetLineColor(4);
>>
>> cout << "drawing ..." << endl;
>>
>> tup->Draw(yyvar+">>"+hDoName,cut);
>> return hDo;
>>
>> }
>>
>>
>> I get the following strange error:
>>
>> hDoName:hVar671
>> hDo:0x947be20
>> drawing ...
>>
>>
>> Error in <TSelectorDraw::Begin>: An object of type 'TH1D' has the same name as the requested event list (hVar671)
>> (class TH1D*)0x947be20
>>
>> What does that mean?
>>
>> -Arthur S.
>>
>> If I try to execute the Draw command by hand using the same TH1D name I get the same error. If w/o ">>" to specifiy histogram to
>> use, it works.
>>
>> If I clone a copy of the histogram |hDo|, change it's name, and use that, so
>>
>> root [18] hDo2->GetName()
>> (const char* 0x956dbd0)"hVar673_2"
>> root [19] tFront->Draw(xxvar+">>hVar673_2",cut)
>> (Long64_t)20934
>>
>> that works too!
>>
>> ?????
>>
>>
>>
>> A.E. Snyder, The Former Group C (TFC) \!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:707-313-0250 Collaboration
>> &
>> Fermi/GLAST
>>
>>
>>
>
Received on Fri Mar 30 2012 - 23:40:47 CEST