Error in <TLinearFitter::UpdateMatrix>

ROOT
1

Hi,

What is the meaning of this error message:
Error in TLinearFitter::UpdateMatrix: matrix can’t be updated - input points not stored
I am using Root 4.04/02, the histogram is initialised, and I use the Fit method as Fit (‘pol0’, ‘Q’).

2

Could you please send this histogram that you are trying to fit? I have no problems fitting a random histogram through Fit(“pol0”, “q”). Are you trying to fix any parameters?

3

I saved it in c1.root. With fit panel, I obtain the same error.
c1.root (13.6 KB)

4

When dumping your histogram, I see that all bins have a null error!!!

junk.Print("all") TH1.Print Name = junk, Entries= 9, Total sum= 524.273 fSumw[0]=0, x=360756, error=0 fSumw[1]=76.2229, x=366260, error=0 fSumw[2]=81.1245, x=371414, error=0 fSumw[3]=69.8335, x=374332, error=0 fSumw[4]=62.9884, x=377438, error=0 fSumw[5]=68.7885, x=380724, error=0 fSumw[6]=72.6766, x=383309, error=0 fSumw[7]=73.2623, x=385230, error=0 fSumw[8]=13.4963, x=388790, error=0 fSumw[9]=5.87982, x=391717, error=0 fSumw[10]=0, x=393870, error=0

So, the histogram cannot be fitted, unless you set correct errors
or specify the option “w” (take all weights=1)

Rene