| T O P I C R E V I E W |
| DeborahH |
Posted - 10/20/2004 : 10:58:04 AM
Origin Version (Select Help-->About Origin): Origin 7
I would like to perform curve-fitting on a function that involves an integral. The data I would like to fit corresponds to the result of the integral. The function including the parameters to be fit corresponds to the function to be integrated? Am I able to perform such an operation with Origin? If so, how? I was unable to find a suitable integration command.
Thanks so much. |
| 3 L A T E S T R E P L I E S (Newest First) |
| easwar |
Posted - 10/22/2004 : 09:36:34 AM
Hi,
If you follow the kbase item on computing integral using script, you will need to set the equation form to Y-Script. If you want to use Origin C, you will need to check the "use Origin C" checkbox.
Easwar
OriginLab
|
| DeborahH |
Posted - 10/21/2004 : 3:56:00 PM
I am unfortuantely still having trouble.
More specifically, I have datasets x and y.
The desired fit for y (with parameters P1, P2, P3, P4, P5 and P6) is:
y=(integral_from_0_to_x(P1*exp(-(x^2)/(P2^2))+P3*exp(-(x^2)/(P4^2))
+P5*exp(-(x^2)/(P6^2))))/(P1*(P2^2)+P3*(P4^2)+P5*(P6^2))
Is it impossible to fit this function with "Form" set to "Equations"?
What is the easiest way to fit this function?
Thanks again. |
| easwar |
Posted - 10/20/2004 : 11:08:11 AM
Hi,
There is a knowledge base item on how to do this with script:
http://www.originlab.com/www/support/resultstech.aspx?ID=121&language=English
and you can look at the end of the following post for a discussion on how to do summation in Origin C while fitting:
http://www.originlab.com/forum/topic.asp?TOPIC_ID=2586
Easwar
OriginLab
|
