How access files in from from CASTOR

Hi All,
I want to access a root file in root via TFile f = .......... but does not work. Can some body help me in this regard.

Regards

Wajid Ali

-----Original Message-----
From: owner-roottalk_at_root.cern.ch on behalf of Arthur E. Snyder Sent: Thu 4/16/2009 10:38 PM
To: Rene Brun
Cc: roottalk_at_lxbuild091.cern.ch; Arafat Gabareen Mokhtar; Stephen Jacob Sekula Subject: [ROOT] Uncertainty on error access ..  

Hello,

I guess this is really, underneath a minuit problem:

How to you get access to the uncertainy in the error printed on the fit output?

This can be substantial even when status assigned to the error matrix is "3" indicating all is well.

I can't find any function that will let me obtain the uncertainty on the error within my root program (that's scanning fit).

-Art S.

PS. this wouldn't matter much normally, but in this case I'm taking the quadrature difference between nominal fit and fit with some other parameters released in order to get the contribution to the error from the released parameters. When the difference is small a 5-10% error can matter a lot ..

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