I have an ntuple with a couple of leaves in a tree. I want to write a C file to make a graph using two leaves for the x and y axis, by utilising , but I don’t know how to point to the leaves in the tree.


To accomplish your task, you have to

  • open a TFile
  • get the TTree
  • assign the address of your class to the appropriate branch
  • loop over the events in the branch and assign to x and y vector

All these steps are extensively documented in examples in
tutorials/tree . What is not clear ?