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Graphical objects do not appear

No graphical objects have appeared after their creation, for instance, TBrowser, TCanvas etc:

import ROOT
b = ROOT.TBrowser()
c = ROOT.TCanvas()

Such behaviour does not take place in the previous ROOT versions, in particular, in version 6.14.04 it works fine.

ROOT Version: 6.22/02
Platform: CentOS Linux release 7.8.2003 (lxplus)
Compiler: GCC 4.8.5
Python: 2.7.5

Hi @kot,
does running the code with python -i (note the -i) solve the issue?
What if you run those lines in the interactive interpreter rather than in a script? Also if you are on lxplus did you connect with ssh -XY to get X11 forwarding? Are there warnings or errors printed on screen?


Dear Enrico,

Thank you very much for the prompt response.

Python is run in an interactive mode, not as a script.
I connect to lxplus via MobaXterm with enabled X11-forwarding. Please note it works fine with ROOT 6.14.04.
No warnings, either errors are thrown

The reason is probably that ROOT is running in batch mode (ROOT.gROOT.IsBatch() probably returns True).

I get the same result when using 6.14/08 from the LCG releases (source /cvmfs/sft.cern.ch/lcg/views/LCG_94a/x86_64-centos7-gcc8-dbg/setup.sh).

What is a working setup on current lxplus?

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Dear Enrico,

Yes, you are right,
ROOT.gROOT.IsBatch() returns True

Dear Enrico,

Setting Batch to False resolves issue: ROOT.gROOT.SetBatch(False).
Thank you very much!

Best regards,

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