Finding one value for whole histogram error

Hello,

I have a weighted 1D histogram which my variabe is on the x axis and the y axis shows the number of particles.
I need to find the error of my variable . I’m looking for one error value and not series of error values like an error histogram or error bars cause I should put this value in an equation and solve my question.
Is there any way to find the average error between two values of the histogram? i.g minimum and maximum bins?
Is it possible by calculating all Errorbins and then divided it by whole number of bins and getting the average?
Please let me know if my question is not clear,

Bests,
Donya

Hi!

What you say sounds like you want to obtain the error on the mean, see:

http://root.cern.ch/root/html/TH1.html#TH1:GetMeanError

Best,

Sebastian

Hi Sebastian,

Thank you, It Sounds exactly what I want but I have another question.
I checked the link it says that this function should be commanded before filling the histogram
but my histogram is ready now, does it mean it doesn’t work now if I apply on my histogram ? or
the result would not be correct ? Do you have any idea?

Bests,
Donya

Hi!

You can user your filled histogram. The sentence you refer to is only about the under and overflow bins.

Best,

Sebastian

Oh, yeah you’re right, sorry for my mistake.
Thank you again for your guideline.

Bests,
Donya