Say I want to fit a gaussian to a histogram which is contained in a rootfile and is named h1.
The code I use is the following (using pyroot):
file = rt.TFile(rootfile, "UPDATE") file.ls() histo = file.Get("h1") histo.Fit("gaus") file.Write() file.Close()
This works but it always creates a new histogram with the fit. So I get the original histogram called h1;1 and a copy of the histogram where the fit is shown called h1;2. When I rerun the code with the same rootfile again I get another copy plus the fit h1;3.
How can I write the code so that no copy is created but the fit is shown in the original histogram. And ideally, when I rerun the code, the previous fit should get deleted and the new fit should show (say that in the second run I want to try a landau fit and not a gaussian).