If there is an example of how to access the TMVA result.root by code instead of TMVA::GUI? Graphical interfaces cannot be forwarded using jumper server. So I can not get the access to the TMVA::GUI. How can I access the tmva result through codes. And I think it will be more convenience to get the output through code.
I’m not sure as to whether X11 forwarding is supported in conjunction with the -J option, but perhaps you can do $ ssh -X -J email@example.com firstname.lastname@example.org.
Otherwise, you should be able to do it (provided that it is allowed by the remote end), a single step at a time, i.e. first by issuing $ ssh -X email@example.com, and afterward $ ssh -X firstname.lastname@example.org.