Re: Accesssing fit parameters and errors

It would be nice if root Print commands could take ostream as an argument so one could print to a file, but that doesn't work. I use cut&paste sometimes, but it I want to print a lot of 'em to files I have to use GetParError or GetParErrors (returns an array [a]).

[a] a pointer to the array fParErrors.
virtual Double_t *GetParErrors() const {return fParErrors;}

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On Mon, 5 Feb 2007, Roger Mason wrote:

> Hello,
>
> I write the parameters of a fitted TF1 into a root file. I need to
> recover the fit coefficients and their errors for tabulation,
> presentation etc.
>
> I have the following questions:
>
> (1) I can print the parameters using:
> f->GetObject("fit",fForm)
> fForm->Print()
> (fForm being a pointer to the TF1)
>
> Is there an easy way to export the coefficients into a text file? They will
> eventually go in a LaTeX document.
>
> (2) I can access the errors on the fit coefficients as
> fForm->GetParError(0) etc...
> Am a correct in assuming the only way to access the errors is to loop
> over them?
>
> Thanks,
> Roger
>
>
Received on Mon Feb 05 2007 - 21:13:09 CET