I need to open a ROOT file containing several histograms that I want to draw in a canvas. I get them with Get() and then I do a SetDirectory(0) (otherwise the histograms are not drawn).
First question: in order to have the histograms displayed is it mandatory to use SetDirectory(0) is there another way?
Second question: is there a way to avoid calling SetDirectory(0) individually for all histograms (the names do not follow a simple pattern such that I could use a regexp or similar)? I tried AddDirectory(kFALSE) but no success.
Many thanks in advance!
ROOT Version: 6.21/01
Platform: Ubuntu 18.04
Compiler: Not Provided