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couturier
France
291 Posts |
 Posted - 06/29/2016 : 06:03:14 AM
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Origin Ver. and Service Release (Select Help-->About Origin): 2016
Operating System:win7
Hi,
I was wondering how to perform a 3d linear fit (or any 3d curve fit).
I'm talking about curve, not surface.
Thanks for the help. |
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Sam Fang
291 Posts |
Posted - 07/05/2016 : 03:06:32 AM
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You can define the fitting function with two dependent variables in Origin. Origin's fitting function supports multiple dependent variables.
e.g. for 3d line, you can define it as:
y=a*x+b;
z=c*x+d;
If you think x is also not accurate in input data, you can choose ODR iteration algorithm.
Sam
OriginLab Technical Services |
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couturier
France
291 Posts |
Posted - 07/07/2016 : 04:35:47 AM
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Thanks a lot Sam,
I'm defintely not familiar with multi dependent variables fitting and couldn't get how to properly define the function.
Could you give further details and step by step how to ?
Thanks |
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Sam Fang
291 Posts |
Posted - 07/08/2016 : 04:06:51 AM
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It is same as general fitting function.
In Fitting Function Organizer or Fitting Function Builder, you should define two variables y, z in Dependent Variables box. In Function Body box, you should define two expressions:
y = a*x+b;
z = c*x+d;
Note that for this type of fitting, it doesn't support graph data, you should choose input data from worksheet. In NLFit dialog, you can choose two columns for dependent variables. You can also choose ODR algorithm, which will allow x in input to be varied.
You can add fitted data to 3d line graph in Plot Setup dialog after fitting.
We will add two built-in 3d curve fitting functions in next version.
Sam
OriginLab Technical Services |
Edited by - Sam Fang on 07/11/2016 07:18:23 AM |
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goffbeach
USA
1 Posts |
Posted - 07/12/2016 : 01:43:00 AM
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I'm not as good as you all guys uhm can I have some help about multi dependent variables fitting. I don't know how to define the function.
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Topic |
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3D curve fitting