Since both the versions of python were not working on simultaneous installation, I now have configured ROOT fresh with only Python2. Therefore, I won’t be able to test what you are asking.
But, my guess is that import ROOT should work. There was no problem with the installation, only running pyroot is the issue.
That was actually my intention, to test PyROOT: by running import ROOT from Python, we can check if PyROOT is (minimally) working. It might be that your dual installation was ok, but you hit the problem with that failing tutorial.
Ok, that’s good. For what concerns the tutorials, we’ll fix the failing ones asap. Please work on the ones that are ok for now (which should be most of them).
As requested by @Wile_E_Coyote in a private message, and regarding the python2 error reported (redefinition in the _cppyy_internal namespace) I confirm I can reproduce it. That error indicates that libcppyy is being loaded twice. By having a look at the code of demo.py it seems that running TPython commands from Python is triggering that second load. I need to have a closer look to confirm, this is also https://sft.its.cern.ch/jira/browse/ROOT-10844 .
I can’t say, can you copy-paste the full output of the cmake configuration please?
Actually, do you actually not have cling? My build also reports no, so that value might be wrong (i.e. could be a bug or non-intuitive behavior on the part of root-config --has-cling, will have to investigate). Can you start the ROOT prompt with root and type C++ code in there?
EDIT: nevermind root-config --has-whatever, it prints no for anything that is not listed in root-config --features. Super weird behavior.
Actually, it seems to me that this is the expected behavior … root-config --features returns a string with all compiled-in features and root-config --has-whatever returns yes / no depending if whatever is actually compiled-in (can easily be tested from e.g. shell scripts).
So, shall I just ignore this. Actually, I have problem adding two TH1F histograms in TBrowser.
After opening a ROOT file in the TBrowser, I select one of the histograms and then right-click to Add, I get the following warning:
Warning in <TRootContextMenu::Dialog>: data type is not basic type, assuming (int)
Following this, when I write the name of the same histogram in both the places of resulting panel, then I get the following error:
Error in <TClingCallFunc::IFacePtr(kind)>: Attempt to get interface while invalid.
Error in <TClingCallFunc::Exec(address, interpVal)>: Called with no wrapper, not implemented!
Am I doing anything fundamentally wrong?
You can use histograms from this file: CL16.root (65.9 KB)