Processing only specific entries of a TTree

Hello,

I'm trying to write a piece of code that writes a portion of a TTree out to a CSV file based on some pre-selection criteria.

I know TTree has the function GetEntries("selection") that gives me the number of entries that match the criteria and I can use this too to limit entries that I use in for example TTree::Draw, but it seems I can't easily iterate over those TTree entries, but would instead have to process every entry and check that the variables match the conditions I had set. Knowing that the cut power is an order of magnitude I'd think the code would be more optimal if I could just process the pre-selected entries.

I'm currently looking into TTreeCloner etc, but any recommendations would be helpful. Also, if there's an easy piece of code to convert a TTree made of basic variables to a CSV, then even better...

Mario Kadastik, PhD
Researcher

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  "Physics is like sex, sure it may have practical reasons, but that's not why we do it" 
     -- Richard P. Feynman