Calculate the average histogram of various histograms

Dear kSmith,

Thank you very much for your answer!
Indeed it doesn’t seem pretty straightforward to calculate the mean histogram.

The thing is that I don’t seem to understand how to use your code.
As far as I understand, I have to include your code into mine and then call your method.
I would expect to call it using something like

This means that I have to create a vector and fill it with the desired histograms, but I don’t know how to do that, since the desired histograms are part of a root file.

Any advice on how to use your method?

Thank you very much in advance!