The Origin Forum
File Exchange
Try Origin for Free
The Origin Forum
Home | Profile | Register | Active Topics | Members | Search | FAQ | Send File to Tech support
Username:
 Password:
Save Password
Forgot your Password? | Admin Options

 All Forums
 Origin Forum
 Origin Forum
 NLSF different Levenberg-Marquardt algorithms?		  New Topic  Reply to Topic
 Printer Friendly
Author Previous Topic Topic Next Topic Lock Topic Edit Topic Delete Topic New Topic Reply to Topic

Dominik Paulkowski

Germany
Posts
Posted - 04/16/2007 :  10:37:51 AM  Show Profile  Edit Topic  Reply with Quote  View user's IP address  Delete Topic
Origin Version (Select Help-->About Origin): Origin7.5G SR6 (v7.5886)
Operating System: Windows XP

Hi there!

My question aims at the non-linear fit modul of Origin. When I use the same user-difened fit function with the same initial condition in different programms, I got different coefficients/results. Both programms use the Levenberg-Marquardt algorithm to fit the data.

The curve fit with Origin looks very well. But I cannot explain the reference material. So I could not use this values for the right sample. The other programm have different coefficients and can all this. But I want to use Origin to fit my data.

Why can there be so different results? Any ideas?

A tolerence of 1E-190 in Origin should be right enough. Chi^2 is in both programs a very big value. R^2 is near 1 in both programms.

Ciao,
Dominik

-------------------
:-Dipl.-Phys. Dominik Paulkowski
Fraunhofer Institute for Surface Engineering and Thin Films (IST)
Braunschweig
Germany

larry_lan

China
Posts
Posted - 04/16/2007 :  11:23:50 AM  Show Profile  Edit Reply  Reply with Quote  View user's IP address  Delete Reply
Hi Dominik:

First of all, it's normal that results from different software are slightly different.

If you think the results differ too much, please send your testing data, the fitting function, the name of the other software, and describe your question in detail to tech@originlab.com, we will try to figure out what's the problem.

Thanks!

Larry
OriginLab Technical Services
Go to Top of Page
  Previous Topic Topic Next Topic Lock Topic Edit Topic Delete Topic New Topic Reply to Topic
 New Topic  Reply to Topic
 Printer Friendly
Jump To:
The Origin Forum © 2020 Originlab Corporation Go To Top Of Page
Snitz Forums 2000