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czarny91
4 Posts |
 Posted - 02/26/2019 : 10:42:14 AM
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Hello,
I would like to ask if you can fit parameters a,b,c following equation:
When I tried to do it in Origin software (function type: expression), however, without success. I think the problem lies in the boundary of the integral, which is also fitting parameter. Can you do it in a simple way in Origin programm, if it is at all possible? In practice, the given value of parameter c is assumed and on the basis of which the other two parameters are fitted.
Thank you for your help |
Edited by - czarny91 on 02/26/2019 11:32:09 AM |
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YimingChen
1607 Posts |
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czarny91
4 Posts |
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YimingChen
1607 Posts |
Posted - 02/26/2019 : 11:47:06 AM
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Please check figure below:
James |
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czarny91
4 Posts |
Posted - 02/27/2019 : 03:57:03 AM
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| It helped, an the programme started to fit parameters. However, I wonder if you can change other setting for example number of iterations. The fitting procedure is only one time. |
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czarny91
4 Posts |
Posted - 02/27/2019 : 07:56:52 AM
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| What does the following communication mean: "System variable "X" is not declared inside function but used"?. When some parameters are stopped, this communication appears. |
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YimingChen
1607 Posts |
Posted - 02/27/2019 : 3:19:01 PM
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Hi,
In NLFit dialog, under Settings tab, select Advanced in left panel, you can then set Max. Number of Iterations in the right panel. For the fitting, you may need to set initial guess of the parameters carefully. You can send your data to <tech@originlab.com> for us to check further.
James |
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Unusual fitting integral function