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
 All Forums
 Origin Forum for Programming
 LabTalk Forum
 Finding equation controlling 3 variables

Note: You must be registered in order to post a reply.
To register, click here. Registration is FREE!

Screensize:
UserName:
Password:
Anti-Spam Code:
Format Mode:
Format: BoldItalicizedUnderlineStrikethrough Align LeftCenteredAlign Right Horizontal Rule Insert HyperlinkUpload FileInsert Image Insert CodeInsert QuoteInsert List
   
Message:

* HTML is OFF
* Forum Code is ON
Smilies
Smile [:)] Big Smile [:D] Cool [8D] Blush [:I]
Tongue [:P] Evil [):] Wink [;)] Clown [:o)]
Black Eye [B)] Eight Ball [8] Frown [:(] Shy [8)]
Shocked [:0] Angry [:(!] Dead [xx(] Sleepy [|)]
Kisses [:X] Approve [^] Disapprove [V] Question [?]

 
Check here to subscribe to this topic.
   

T O P I C    R E V I E W
frontliner Posted - 08/27/2005 : 3:45:35 PM
Origin Version (Select Help-->About Origin): 7.5 SR0
Operating System: Windows XP

Hi everybody,

I am a new user for origin, and I have a problem I can't solve it.
I have database consists of 3 column of data, Z, X/U, Y/U, where Z is the requested variable or requested controlling equation of type Z=f(X/U,Y/U) so we have 4 variable here.
How can I find the equation Z=f(X/U,Y/U) ?
Any help is really appreciated!
Thanks
Regards
3   L A T E S T    R E P L I E S    (Newest First)
easwar Posted - 09/02/2005 : 09:41:50 AM
Hi frontliner,

Are you looking for LabTalk script, or procedure to manually fit the data using the NLSF tool?

Looks like what you need to do is fitting with multiple independent variables:
Please take a look at the following:
1> Knowledge base item on our website, searchable from Support area:
http://www.originlab.com/www/support/resultstech.aspx?ID=57&language=English
2> Origin Help file topic:
Fitting With Multiple Independent Variables

As for programmatic fitting, please look at the Programming Help file and the LabTalk Language Reference section. There you can look at the NLSF object and its properties and methods. You can then use NLSF object and set properties such as number of indep vars, which column to use for which indep var etc. You should first create the FDF with your fitting function and then you can programmatically use the FDF from your script.

Easwar
OriginLab


frontliner Posted - 09/02/2005 : 07:04:36 AM
I know this should be done by script.
I have 3 columns of data, A(X), C(Y) and B(Y) where B(Y) is Z (the wanted equation).
Assuming the script is right, would you please correct me with the following steps:

1-Analysis>Non-linear curve fit>Advanced fitting tool
2-Function>new then create my function with name user1 having the wanted parameters p1,p2,p3, then I select it
3-Scripts>before fit> enabled then type in your script
4-I checked (Same X as fitting data)
5-I highlighted the 3rd column in my database B(Y)
6- I clicked on "Basic mode" then click on "Start fitting"

I am sorry for being a beginner, any help is really appreciated
Thanks a lot
frontliner Posted - 09/02/2005 : 06:54:36 AM
Nobody out there for help? :(

The Origin Forum © 2020 Originlab Corporation Go To Top Of Page
Snitz Forums 2000