Re: [ROOT] Fitting over multiple ranges

From: Rene Brun (
Date: Thu Jul 08 2004 - 19:57:07 MEST

see tutorial fitExclude.C

Rene Brun

On Thu, 8 Jul 2004, Alberto Pulvirenti wrote:

> Dear ROOTers,
> I encountered a problem which I wish to solve.
> I have a plot which looks like the sum of two gaussians with similar 
> mean and quite different constant/sigma values.
> I would like to fit such a histogram with the sum of two gaussians.
> Given that one of the two is smaller and wider, I wished to try to fuit 
> a gaussian in the middle part of the histo (and I know how to do this)
> And the other should be fitted at the same time, in the two periperical 
> regions.
> Say, if we divide the histo into three regions: (-A, -0.1), (-0.1, 0.1) 
> and (0.1, A), how can I perform a fit with the same function, and 
> simultaneously in the two ranges (-A, -0.1) + (0.1, A) ?
> (I tried with two separate gaussian fit on the two intervals, but the 
> result is not satisfactory).
> Thanks.

This archive was generated by hypermail 2b29 : Sun Jan 02 2005 - 05:50:08 MET