Assign two independent errors in histogram?

Dear rooters,

Is there any method to assign two different errors in histogram?
For example, I would like to show a distribution(actually 1D histogram) with statistics and systematics in the same time (per bin).

But, I can find how to do it yet, so could you share your wisdom?


Use 2 TGraphErrors


Thanks so much!
Really I never imagine this simple way at all. :slight_smile: