Re: integral using TF1

From: Edmond Offermann <>
Date: Tue, 26 Apr 2005 18:57:47 -0700 (PDT)

Hi Shamin,

Some possible pointers :

  1. Your histogram is too coarsely binned comapred to the structure you want to fit .
  2. Calculate the integral of the expression as a function of par[0] and par[1] You know the errors in the pars (and could also get their correlation) . Now it is a straightforward error-propagation exercise to ge the error in the integral . Maybe the answer is well inside the error .
  3. You are fitting the histogram points NOT the function integral; if point 1) is ok, one would expect also a correct (see 2)) integral . However, you could re-parametrize your function expression such that it guarantees that the function integral equals the histogram sum .


Received on Wed Apr 27 2005 - 03:57:57 MEST

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