Error bars when making histogram


I am having some problems getting the error bars I want on a histogram. As an example, here is the kind of error bars I would want (the checkered bits):

I understood that the way to obtain such an effect is to use the draw option “E4”, but once I try to apply this in my code, the histogram disappears. However, it reappears if I use histogram.Draw(“h”). I must also mention that I am using ATLAS Style. I have attached the code that I am using to produce the histogram.

Thank you,
Patrick. (1.9 KB)

Try with:


Now I can see it, thank you! However, it’s not quite like the effect displayed in the above picture. It seems to me like the signal and the errors, in the example I provided, are two separate histograms overlayed. Is my suspicion correct?

Kind regards,