Asymmetric SetBinError for TH1F (April, 2008)

Hello all,

In the following topic, the subject of asymmetric errors for TH1F is addressed. However, this topic is dated Jan 19, 2002. … /0249.html

Does the current version of ROOT support histograms with asymmetric errors? I cannot find anything in the current source code for TH1F…

Thank you,

no changes. Use TGraphAsymmErrors.
You can easily build a TGraphAsymmErrors from a TH1* hist with

TGraphAsymmErrors g(hist)

Hi Rene,

Thank you for your quick reply.

I was able to build a TGraphAsymmErrors from a TH1* hist with no problem. However, ultimately I need to pass the TH1 to a RooDataHist, which I will then fit with a RooAddPdf.

I don’t see anything in the RooDataHist source code which gives me any idea how to do this. I only see the option to pass a TH1* object, not a TGraphAsymmErrors.

Is there a way around this?

Thank you,


I might be able to help here, but I am slightly confused by what you want.

Do you want to construct a RooDataHist from a TGraphAsymErrors,
or do you want to do the reverse? The latter is already possible, the
former is not, but is fairly easy to add for me.


Hi Wouter,

I would like to construct a RooDataHist from a TGraphAsymErrors. Any help would be greatly appreciated!

Many thanks,

Hi Pablo,

I’ll add support for that. It should be available next week.


Thank you very much!!

Hello Wouter,
Currently is possible construct a RooDataHist from a TGraphAsymErrors? I dont know how to do this

Many thanks,