bug in TTree::Draw()?

From: S.J.M. Peeters (Simon.Peeters@cern.ch)
Date: Sun Apr 11 1999 - 14:31:43 MEST


Hi ROOTers,

I'm using ROOT v2.20 on the hp.
I have noticed a difference between Draw() when called in a macro and
directly in CINT. The macro executes incorrectly in CINT while the code
typed in directly in the interpreter works correctly. The macro is
appended.

The result should be a plot of the overlaps in a disk, so points in a disk
shape, centered around 0. The macro however plots the points but sets any
coordinate smaller then 0 to 0.  This results in a plot of the disk in the
first quadrant with thick lines at x = 0 , y > 0 and y = 0 , x > 0.
If I type the command by hand in the interpreter the correct plot appears.

I've checked with the new v2.21, the problem also occurs there.
(the fancy startup screen still calls it version 2.20, while the 
 message in the text window calls it 2.21/08).

Cheers,
Simon Peeters.

-- The macro --

{
  gROOT->Reset();
  gStyle->SetOptTitle(0);
  gStyle->SetPaperSize(7.5,7.5);

  TFile *file = new TFile("overlap.root","READ");

  TCanvas *canvas = new TCanvas("canvas", "canvas",0,349,500,500);
  canvas->Range(-2.75,-2.75,24.75,24.75);
  canvas->SetFillColor(19);
  canvas->SetBorderSize(2);

  TH2F  *hframe = new TH2F("hframe","",210,-21,21,210,-21,21);
  hframe->Draw();

  TPaveText *title = new
  TPaveText(-0.0332663,22.4778,21.9224,24.1674,"br");
  title->SetFillColor(10);
  title->SetFillStyle(0);
  TText *text = title->AddText("pixeldisk1, r/phi");
  title->Draw();

  check_overlaps->Draw("x1:y1","Dice1 == 2 && Dice2 == 10","same");
}


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