[ROOT] Drawing a line in histogram in log mode

From: Reinhardt Chamonal (chamonal@ph.ed.ac.uk)
Date: Wed Jul 17 2002 - 12:54:06 MEST 

Hi,
I have a minor problem:
I am drawing a simple vertical line on my histogram as follows:
    Int_t binminmean = xaxis->FindBin(tabMean[i]);
    Double_t maxvalue=pedestal->GetMaximum();
    l=new TLine(binminmean,0,binminmean,maxvalue);
    l->SetLineColor(38);
    l->Draw();
It works fine until I decide to change the Y coordinate to logarithmic 
scale with
    gPad->SetLogy();	

The line has an ofset (it's at 1 instead of 0) and goes off the histogram.
What is wrong ?

I tried stuff like:
l=new TLine(binminmean,log(0),binminmean,log(maxvalue));
without success...
if I put 1 instead of zero it starts at 10 if I put 2 it start at 100 
etc..

I am using root 3.03.06

Cheers


------------------------------------------------------------
 Reinhardt CHAMONAL            The University of Edinburgh  
                               Dept. of Physics & Astronomy 
 email: chamonal@ph.ed.ac.uk   King's Buildings, JCMB, 5301 
                               Mayfield Road                
 phone: +44-131-650 5307       Edinburgh, EH9 3JZ           
 
 web: http://www.ph.ed.ac.uk/~chamonal/
      http://www.reuh.fr.st
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