Creating a TTree with a per-entry integer in Python

ROOT
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1

Hi,
I’m trying to fill a TTree containing one integer per entry. For example, if the entries in my TTree are events, then what I want to have is an integer with the event number. It’s exactly one integer per entry (as opposed to e.g. electron pTs, which have to be inside an array/vector as there can be several electrons in an event).
I’m wondering how to do it in Python. I found a relevant tutorial here, and it says:

If you fill a TTree in C++ , you can pass a double as a reference, called the address of the branch:

TTree tree("tree_name","tree title");
Float_t px;
tree.Branch("px",&px,"px/F");

In python however, you will need to use an array instead, for example the array class.

Is it true that even though my variable is not an array/vector, I have no other choice but to put it in an array/vector when filling my TTree in Python?
Thanks!

ROOT Version: 6.32.08
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Compiler: does not matter

2

Apparently yes, looking at the ROOT: TTree Class Reference