Fit results SOMETIMES not drawn w/o gPad.Update()


The attached script SOMETIMES draws the line of the fit results and SOMETIMES do NOT; with gPad.Update() after Draw()ing, the line is always drawn.
A C++/Cling version never fails even w/o the Update().
Also, the example in Fitting Histograms' of theROOT User’s Guide’ always draws the line.

Why? What’s the difference? :confused:

On Linux (fedora-20, i386), Python 2.7.5, ROOT 6.02/00 Built by myself From git tag v6-02-00, 30 September 2014

exp.root (3.94 KB)
expFit.C (331 Bytes) (405 Bytes)

Yes, gPad->Update() is needed.