I’m using the functions GetEffectiveEntries() and Integral() on histograms which are scaled and weighted. Therefore I would have expected the two values to be different of course but proportional. Instead I’m obtaining a strange behaviour. For example I’m reporting some numbers below (Integral() on the left and GetEffectiveEntries() on the right):
Are the histograms scaled with a scalar, or could there be two different sets of data which are scaled independently?
If you are using hist->Scale() then the integral should be updated proportionally. However, this should not change the number of effective entries.
If instead the histogram is generated from some data source, check if some scaling factor is applied only to a subset. This would then skew the integral.
thanks a lot for the reply. I see, I think I have to double-check because these histograms are coming from MonteCarlo samples, managed by another code of which I’m not the responsible.