Minuit2

From: Patrick Dupre <pd520_at_york.ac.uk>
Date: Wed, 3 Sep 2008 00:27:39 +0100


Hello,

I sent already 2 messages about Minuit, but I did not get any feedback !!

Now I am experiencing several problems.
1) Minuit2 has a lot less option than TFitter has, Why I cannot manage the max number of iterations, etc.. how can ROOT:TFitter can ne based on minuit2 and offer more options ? Am I wrong ? arglist offers those options !
2) Minuit does not congerve at all in some circunstancies. I notice for example having to fit a big number : 5e12. the fitter change the value of the parameter, calculate the chi2, finds that it is lower, but finally keep the original value: example:
Density: 4.90049e+12
chi2 1.01073e-05
Density: 4.89951e+12
chi2 1.03073e-05
Density: 4.9049e+12
chi2 9.23127e-06
Density: 4.8951e+12
chi2 1.12318e-05
Density: 4.949e+12
chi2 2.65485e-06
Density: 4.851e+12
chi2 2.26607e-05
Density: 4.9e+12
chi2 1.02068e-05
Density: 4.9e+12
chi2 1.02073e-05

3) When I user Strategy, 2, it crash after a couple of iterations !   ../inc/Minuit2/LASymMatrix.h:226: double& ROOT::Minuit2::LASymMatrix::operator()(unsigned int, unsigned int): Assertion `row<fNRow && col < fNRow' failed.

Should I keep using this package ?

Regards.

-- 
---

==========================================================================
Patrick DUPRÉ | | Department of Chemistry | | Phone: (44)-(0)-1904-434384 The University of York | | Fax: (44)-(0)-1904-432516 Heslington | | York YO10 5DD United Kingdom | | email: pd520_at_york.ac.uk
==========================================================================
Received on Wed Sep 03 2008 - 01:27:50 CEST

This archive was generated by hypermail 2.2.0 : Wed Sep 03 2008 - 11:50:02 CEST