RooFit & TFormula

Hello all,
I realize this may be the wrong forum to ask this question, but I haven’t been able to get a reply on the RooFit specific forum, so I thought I would give it a try. Does anybody out there use RooFit with ROOT v4? If so, has anybody found a fix to the problem of RooFormulaVar (which depends on TFormula) not being able to compile expressions?
I very much need this to work and have been unable to dig through the RooFit source, with which I am unfamiliar, to find the source of the bug.

Thanks in advance,


Did you contact the authors Wouter Verkerke and David Kirkby .



It took me a while to realize that my RooFormulaVar was not working. I found out it worked with an older version of Roofit compiled against ROOTv3.10. I suppose this is running away from the problem rather than confronting it, but it’s a temporary working solution. I describe what I did here: … _id=201226


Tae Min Hong

Wouter will answer your mail as soon as he will be back online.



I cannot reproduce Tae problem with ROOT5 and RooFit 2.07.
suspect that it was a transient problem related to ROOT/RooFit
versions. At some point the interface for inhering from TFormula
changed in ROOT(4), which needed corresponding change in
RooFit. That has happened already quite a while ago, but it means
that certain older versions of RooFit will not work with ROOT4 or ROOT5.