| T O P I C R E V I E W |
| altomare |
Posted - 08/16/2005 : 6:57:39 PM
Origin Version (Select Help-->About Origin): 7.5
Operating System: WinXP
I am trying to fit some dataset using a custom function with a script like
r=exp(-x*a1);
y=f(r);
The output of this fitting function is the y value but I was wondering if it is possible to have origin (using some property of the nlsf object) to create a dataset for the intermediate value r without calculating it afterward (there is a certain number of parameter I have omitted here which would be a pain to get it right).
Is there any way to do it?
Thanks a lot
Fabio
PS I tried to define r as a dependent variable as well but the fit is not working in this case |
| 3 L A T E S T R E P L I E S (Newest First) |
| Leo_Li |
Posted - 08/18/2005 : 04:15:45 AM
Fabio,
You may want to try "After Fit Script" to automate the vector operations on X variable. To do it, pick "Script -> After Fit" menu in Nonlinear Curve Fitting dialog.
Leo
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| altomare |
Posted - 08/17/2005 : 1:14:43 PM
Leo,
unfortunately there are several additional assignment in the script involving vector operation on the x variable (of the fit as well): this is the reason I was hoping there was some way to do it in a similar fashion to nlsf.funcx$ .
I have, in fact, tried to define my variable (r) as additional independent variable in the fit and tried nlsf.funcx1$ and nlsf.funcx2$ (in analogy to nlsf.x1$ and nlsf.x2$) but it didn't work.
Do you have any other suggestion I can try?
Thanks a lot
Fabio |
| Leo_Li |
Posted - 08/17/2005 : 06:25:19 AM
Hello Fabio,
After performing the NLSF fit, you can add a new column to your source worksheet. Assume the title of your worksheet is "Data1", in which Col(A) contains X values, and Col(D) is the new column; run the following script in the Script Window:
Data1_D = exp(-Data1_A * nlsf.p1)
Here I assume that a1 is the 1st parameter, so nslf.p1 = a1.
Leo
OriginLab Corp. |
