`Gaudi::Histograming::Sink::Root` does not set number of entries

Currently, the ROOT sink creates histograms by only calling SetBinContent. This results in the "Entries" field being wrong. For example, the histograms produced in the Gaudi example https://gitlab.cern.ch/gaudi/Gaudi/blob/master/GaudiExamples/src/Histograms/CounterHistos.cpp and https://gitlab.cern.ch/gaudi/Gaudi/blob/master/GaudiExamples/options/Histograms.py#L32 have 50000 entries but looking at the saved root file (screenshot below) we see only 102 (= number of bins).

We should also make sure other quantities are also correctly propagated (e.g. the sum of weights and the sum of squares). The numbers in the json representation should match the numbers reported in the stat box when plotting the histogram. Whenever that is not possible, some sensible defaults should be used (e.g. nan?)

It might also be useful to print summaries with the message service.

changed the description

Let me hijack a bit this issue to mention other improvements needed in the current (toy) implementation :

• be able to split histos into different files
• and to name the files
• be able to add some graphical additions (colors, thickness, etc, etc)

assigned to @sponce

changed milestone to %v36r1

The original issue, that is the number of entries, is now fixed in !1240 (merged) Concerning other quantities, I could not really check them as I even fail to display the histogram in TBrowser right now. @rmatev could you check and report me any other issue ? Thanks !

closed

mentioned in merge request !1320