Re: TTree::Draw and TProfile

Rene Brun (Rene.Brun@cern.ch)
Tue, 28 Jul 1998 12:08:14 +0200

mayer@ik1.fzk.de wrote:
>
> Dear rooters
>
> I tried to fill a profile histogram via TTree::Draw, however the profile
> histogram is being erased and replaced by an ordinary 2d histo. I tried
>
> root [9] hprof = new TProfile("hprof","edtarr vs logSize",100,3.,7.,0.8,4.5);
> root [10] h3.Draw("log10(edtarr):log10(Size)>>hprof",cStd+crad90);
> Warning in <TTree::Draw>: Deleting old histogram with different dimensions
> root [11] delete hprof;
> root [12] hprof = new TProfile("hprof","edtarr vs logSize",100,3.,7.,0.8,4.5);
> root [13] h3.Draw("log10(edtarr):log10(Size)>>+hprof",cStd+crad90);
> Warning in <TTree::Draw>: Deleting old histogram with different dimensions
>
> but both did not work. What is wrong?
> Regards
> Hajo

With the current version 2.00/09, you must specify the option=prof
to generate a profile histogram, eg:
h3.Draw("log10(edtarr):log10(Size)>>hprof",cStd+crad90,"prof");

I have update the development version to not require this option
in case the specified output object is a TProfile as in your case.

Rene Brun