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Getting derived values into matlab variables

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Hello!

I have some trouble getting the value of an average operator into a matlab variable when using comsol through matlab.

What I get when I translate the model into an .m file is this:

model.result.numerical.create('av2', 'AvSurface');
model.result.numerical('av2').selection.all;
model.result.numerical('av2').selection.set([2]);
model.result.numerical('av2').set('expr', 'sqrt((mfnc.Br*d(mfnc.Br,r)+mfnc.Bphi*(1/r)*d(mfnc.Br,phi)+mfnc.Bz*d(mfnc.Br,z))^2+(mfnc.Br*d(mfnc.Bphi,r)+mfnc.Bphi*(1/r)*d(mfnc.Bphi,phi)+mfnc.Bz*d(mfnc.Bphi,z))^2+(mfnc.Br*d(mfnc.Bz,r)+mfnc.Bphi*(1/r)*d(mfnc.Bz,phi)+mfnc.Bz*d(mfnc.Bz,z))^2)');

What I want to do is get the value of 'av2' into a matlab variable. I tried using mpheval and mphglobal but it didnt work, not sure if I am using them right. Does anyone have any ideas?

Thanks in advance!

3 Replies Last Post 2013年11月20日 GMT-5 12:22

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Posted: 1 decade ago 2012年3月16日 GMT-4 09:37
Hi,
I meet a same problem as you.

What I have done is export the derived value into a txt file, then use the matlab function importdata() to load the value.

I appreciate very much if some one can show the direct method which can read directly the derived value.
Hi, I meet a same problem as you. What I have done is export the derived value into a txt file, then use the matlab function importdata() to load the value. I appreciate very much if some one can show the direct method which can read directly the derived value.

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Posted: 1 decade ago 2012年3月23日 GMT-4 15:20
Thanks, I ll try that. Still, there should be a more direct way. It seems pretty basic as a need to be complicated as a procedure.
Thanks, I ll try that. Still, there should be a more direct way. It seems pretty basic as a need to be complicated as a procedure.

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Posted: 1 decade ago 2013年11月20日 GMT-5 12:22
You can put your derived values in table and import the table using mphtable(model, 'tabletag');
This works perfect for Nx2 table but it fails for NxM where M>2. Try and see if this help
You can put your derived values in table and import the table using mphtable(model, 'tabletag'); This works perfect for Nx2 table but it fails for NxM where M>2. Try and see if this help

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