Re: Draw ves Project

Jean-Eric,

I cannot reproduce this problem.
Note that TTree::Project calls TTree::Draw. So, I do not see why the output should be different.
Please:
  -tell us which version of ROOT?
  -send the shortest possible script with a file repducing your problem

Rene Brun

On
Wed, 8 Jun 2005, Jean-Eric Campagne
wrote:

> Dear developpers
>
> I have done the following
> 1) open a ROOT file with a TTree which contains "zp" and "pdg" as variables
> 2) do the tree drawing
> tree->Draw("zp","pdg==211")
> Then just to show for student an other possibility
> 3) create a TH1D* h1 with ("h1","z prod of pi+",100,0,100)
> 4) project the tree on h1 as followed
> tree->Project(h1->GetName(),"zp","pdg==211")
> 5) draw the result
> h1->Draw("SAME")
>
> To my great surprise the 2 plots does not fit each other (see pb.ps
> attached), and this is not just bin to bin fluctuation
> Have you an idea?
> Regards
> Jean-Eric
>
>
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Received on Wed Jun 08 2005 - 12:09:52 MEST