Fit, excluding specified bins

Hello Rooters

I want to perform a gaussian fit on TH2F histogram (lego plot). The top of the random gaussian distribution is cutted away (just a plateau around the center of the gaussian distrubion remains). Now I want to force root to take all bins into account for the fit except some specified bins at the center of the distribution.
So how can I force root to perfom a fit on a histogram without taking for example the bin content of bin [10][20] into account?

Thanks a lot for your help!

Cheers

Christian

easy quick workaround is to set errors of unwanted bins to huge values compared to normal errors of other bins and then fit.

see tutorial $ROOTSYS/tutorials/fit/fitExclude.C

Rene

If you are doing a likelihood fit, this won’t change work.

Charles

Thanks for your replies. I used the method of setting large errors for all bins I wanted to exclude from the fit.

Cheers

Christian