Hi Tommaso, You are right. I have changed the default for the TTreeViewer to be the same as in the TTree::Draw command. The fix is now in CVS. To zoom on the axis of a TGraph, move to the pro version 3.02/07 Rene Brun Tommaso Chiarusi wrote: > > Dear Rooters, > I've tried to plot two variables using the features of > TBrowser's StartViewer. > I dragged the a and b variables (leaves in my data set) onto the x and y > places and then I pressed the > graph button to issue a plot on a canvas. > The result is in the picture > > /afs/cern.ch/user/c/chiarusi/public/aVSb_browser.ps > > The variables a and b are respectively the major and minor semiaxis of > some ellipses, so b MUST be <= a. > Well I startled to the plot since > I saw many point getting below the y=x line (i.e. b>a!!!!!). > > I tried to us<e the scan feature to see which of those were such events > with b>a. > Root told me that NONE of them was "b>a compliant"! > > So I wrote a small script verifying inipendently from Root, and I got the > same result: none of the events was with b>a! > > Then I plotted the same events using the TGraph, and I got the > plot > > /afs/cern.ch/user/c/chiarusi/public/aVSb_graph.ps > > where is perfectly clear that the geometric condition b<=a is completely > respected! > > So, my question is: > Is it possible that the StartViewer way of plotting is made via > histogramming and not via "TGraph-ing" ? > > What do you think about swapping this features ? So Scan's results > could be confirmed directly by StartViewer's plots. > > Thanks! > Tommaso > > P.S. > I'm using old 3.0 version of root. > Do the GetHistogram() or GetXaxis() functions work with a TGraph > (let's say in case if I would like to zoom throug the axis ranges )? > > Thank you very much again. > Tommaso
This archive was generated by hypermail 2b29 : Sat Jan 04 2003 - 23:50:38 MET