| Author |
 Topic  |
|
|
mrkoehler
USA
Posts |
 Posted - 10/31/2007 : 3:08:31 PM
|
Origin Version (Select Help-->About Origin): 7.0
Operating System: winxp
First off, I know next to nothing about Origin, so please keep that in mind.
I have been plotting up two columns of data and then choosing fit Lorentzian and everything has been fine, until now. All of a sudden, nothing I try to fit will fit, it always comes out a straight horizontal line. The plots will fit if I try on another computer, but not on mine. I have tried uninstalling and reinstalling 3 times, but it still doesn't work. If you need anything else to help you help me, feel free to ask.
I would greatly appreciate any help!
Edit: I recently loaded Origin onto 2 more computers. The Lorentzian fit works on one of them but not the other. I don't know if that helps, but it is more information.
Edited by - mrkoehler on 10/31/2007 3:25:36 PM |
|
|
joseph_king
China
Posts |
|
|
mrkoehler
USA
Posts |
Posted - 11/01/2007 : 2:56:52 PM
|
I will do my best to better describe the problem. If there is anything specific you need to know, please ask. Also, I have called technical support once and they helped me some, but I am still having an issue.
To start, I have an Excel file. I open the file in Origin, and select the option to "Open as Origin Worksheet". I then choose 2 columns to plot and plot them. There is one peak in the plot, and it is one that should be easy to fit.
If I go to the toolbar and click Analysis, then choose Fit Lorentzian, I get a flat line with very large xc, w, and A values (in the range of 6E23). I should also mention that I have been able to fit this same peak very accurately on a different computer.
Technical support helped walk me through another way of performing a Lorentzian fit though. If I click on Analysis, then Non-Linear Curve Fit, then Advanced Fitting Tool, then it brings up the "NonLinear Curve Fitting: Fitting Session" window. If I then choose Lorentzian, then the Action option on the toolbar, then Fit and enter an "xc" value that is incredibly close to what it should be, then click 100 Iter., it will accurately fit my plot. If the "xc" value that I enter is not incredibly close, it fits it at some random spot and my values are incorrect. Each time I want to fit a peak, I have to go through this process and hope that I can determine the peak location accurately enough for the program to work.
I've looked everywhere I can think to look to find some kind of difference between the program on my computer and the one on which my peak will fit, but they appear the same. They are the same Service Release, they were loaded from the same disc, and I did nothing different. I have been able to fit peaks on my now-problematic computer in the past, but all of a sudden Lorenztian stopped working correctly.
As I said, if there is any other information you need, just ask.
|
 |
|
|
larry_lan
China
Posts |
Posted - 11/02/2007 : 01:30:20 AM
|
Could you please send your Excel file to tech@originlab.com and let me have a try?
Thanks
Larry
OriginLab Technical Services |
|
|
| |
Topic |
|
|
|
Origin won't Lorentzian fit anything