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Posted: **Mon Jan 09, 2017 3:59 am**

I have found a strange behaviour of esfit() function with multicomponent fitting. It looks that simulation function is called for each spin system separately but the weight coefficient Sys.weight must be treated inside the simulation function. I think that follow construction is used into esfit() function:

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y=simfunction(Sys{1},Exp,Opt)+simfunction(Sys{2},Exp,Opt)+simfunction(Sys{3},Exp,Opt)+...

I propose to modify the function esfit() to call the simulation in multicomponent manner, if it is not too hard, of course. I.e. using follow calling:

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y=simfunction({Sys1,Sys2,...},Exp,Opt)

Posted: **Mon Jan 09, 2017 12:53 pm**

This will not result in observable changes, so it is unclear why this is needed. Do you have a use case where this makes a difference?

Posted: **Tue Jan 10, 2017 12:47 am**

It should provide the simplest way to fit the experimental parameters by custom simulation function. Now it is impossible without some tricks.
viewtopic.php?f=3&t=371

Posted: **Tue Jan 10, 2017 9:35 am**

Please post a short script of what you would like to do which is not possible now.

Posted: **Tue Jan 10, 2017 12:10 pm**

OK, let's vary MW frequency. The function esfit() does not allow varying of Exp parameters (although it would be nice), so we have to use custom simulation function:

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function y = mysim(Sys,Exp,Opt);
if isfield(Sys,'mwFreq'),Exp.mwFreq = Sys.mwFreq; end
y = garlic(Sys,Exp,Opt);

This will be working only for single component spectrum:

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Sys.mwFreq = 9.65;
Sys.g=2;
Vary.mwFreq = 0.05;
Exp.Range =[...];
esfit('mysim',data,Sys,Vary,Exp);

For two components we'll obtain separate MW frequency for each one:

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Sys1.mwFreq = 9.65;
Sys1.g=2;
Vary1.mwFreq = 0.05;
Sys2.mwFreq = 9.65;
Sys2.g=2.05;
Vary2.mwFreq = 0.05;
Exp.Range =[...];
esfit('mysim',data,{Sys1,Sys2},{Vary1,Vary2},Exp);

There are no ways to keep Sys1.mwFreq and Sys2.mwFreq equal during fitting.
If calling of the simulation function from esfit() will be changed as I propose, it will be possible to make correct frequency fitting:

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function y = mysim(Sys,Exp,Opt);
Sys1=Sys{1};
Sys2=Sys{2};
if isfield(Sys1,'mwFreq'),Exp.mwFreq = Sys1.mwFreq; end
y = garlic(Sys1,Exp,Opt)+garlic(Sys2,Exp,Opt);

The varying of MW frequency is required because Bruker EMX spectrometer writes its value only for last spectrum in sequence. The frequency drift due to fine tune is ignored.

Posted: **Tue Jan 10, 2017 1:33 pm**

That makes sense. We will add this to our list of improvements.

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Modification of esfit() function

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