Hello,
If from a TH2F histogram we make a TProfile using TH2F::ProfileX() I thought that for each value of the bins in X the TProfile gives its mean Y value (the points in the TProfile) and its RMS (the vertical error bars in TProfile).
I have attached the file Histo2D.root. There are two plots inside:
TotalEclusVsE, which is a TH2F histogram and TotalEclusVsE_pfx which is a TProfile calculated from the first one doing:
TotalEclusVsE->ProfileX();
If we plot both plots together:
TotalEclusVsE->Draw();
TotalEclusVsE_pfx->Draw(“same”);
Clearly the points in TotalEclusVsE_pfx are the mean of Y for each bin, but the errors are too small to be the RMS.
What are they? The error on the mean?
I would like to have the real RMS as the error bars in TProfile to have an idea on how the Y values are spread around the mean .
Cheers.
Histo2D.root (19.5 KB)