Generated Events in EventNtuple?

[sophiemiddleton]

@oksuzian asks:

is there a plan to propagate the number of generated events into EventNtuple?
For instance, in order to estimate the CE reconstruction efficiency we have to start from the number of generated events, which (I think) is currently not present in EventNtuple.

Live time too.

[sophiemiddleton]

This links with MDS discussion on how to keep track of the normalization products

[AndrewEdmonds11]

Sorry, I must have missed this issue. The number of generated events is in the genCountLogger folder that's also generated. I don't think the EventNtuple itself is the place to store run-level information. We could think about creating a "RunNtuple" but at the moment the genCountLogger histogram and similar is sufficient

Here's how to use:

TFile* evn_file = new TFile("nts.mu2e.CeEndpointOnSpillTriggered.MDC2020au_best_v1_3.001210_00000000.art", "READ");
TH1F* hNumEvents = (TH1F*) file->Get("genCountLogger/numEvents");

// numEvents is a one-bin histogram where the bin content is the number of generated events
int n_gen_events = hNumEvents->GetBinContent(1);