[ROOT] TTree::Scan() and TTree::Draw() selection different?

From: Hannes Sakulin (Hannes.Sakulin@cern.ch)
Date: Fri Aug 16 2002 - 12:54:13 MEST 

Hello,

I wanted to use TTree::Scan() to dump a few events that I had Drawn from a
Tree. It seems that TTree::Draw() and TTree::Scan() use a different
selection. While Draw() finds the events (in the example it is 1 event),
Scan() does not find them. Is there any explanation for this?
root [0] TFile f("gmt_1.root")
root [1] h1.Draw("Event", "(abs(Etac-Eta2dsk)>0.1) && (Eta2dsk <99) &&
(Ncsc==1)")
<TCanvas::MakeDefCanvas>: created default TCanvas with name c1
(Int_t)1
root [2] h1.Scan("Event", "(abs(Etac-Eta2dsk)>0.1) && (Eta2dsk <99) &&
(Ncsc==1)")
************************
*    Row   *     Event *
************************
************************
==> 0 selected entries
(Int_t)0

The behavior is the same in versions 3.02/07, 2.03/02, 3.03/07. You can find
the Tree in ~hsakulin/public/gmt_1.root.

Cheers,
  Hannes.
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Hannes Sakulin
Institute for High Energy Physics, Vienna, Austria
CERN / EP                           Phone: +41 22 767 7372
CH-1211 Geneva 23, Switzerland      Fax:   +41 22 767 8940
E-mail: Hannes.Sakulin@cern.ch
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

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