Hi there,
I was trying to fit a histogram which has range (0,200) by half a gaussian function but it does seem to work for the interval I specify (which is from 10 to 200 ):
It turned out that even though the mean value was fixed to 0, the fit still gives a mean value at about 40.
I also tried ab_delta_z->Fit(“gaus”,“”,“”,10,200) and it gives much better fit results but I cannot fix the mean value to exactly 0. Any solution to this?
First, welcome to the ROOT Forum!
Then, maybe @jonas can help with this, but I guess more details are needed, like for example the data (or its shape) you’re trying to apply your fit to…
Hi, Sorry I can’t post the plot here but the shape is just like the right part of a gaussian (x axis from 0 to 200). The bins close to 0 are not fully filled so the histogram looks like a bell without the peak/well in the centre. That is why the fit needs to be performed over [10,200].