I have written a class to write (for now) a simple ntuple (TNtuple) as an
summary of the data-aqcuisition I am running.
Thinking there was a bug on my side, I in the end printed every entry to
go into the ntuple on a small bit of data. It turned out that I could plot
the values expected. Running the same again on a big amount of data,
the ntuple got filled as I expected, but the TTree->Draw() failed to draw
the correct distribution of data!
As an illustration:
STNtuple->Draw("preamp_bias") -> this draws a single peak of hight 11648
at x = 211.6 (nentries = 23296!)
STNtuple->Draw("preamp_bias","preamp_bias < 200") -> this draws a single
peak of hight 11648 at x = 147.2
Of course I would like the first command to draw both peaks!
I am using ROOT version 2.21/08 on linux.
Many thanks for any useful hints on how to solve this,
Simon Peeters.
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