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Undefined variable problem

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Trying to do a 3d frequency domain simulation, but it keeps showing this error message:

Undefined variable. - Variable: comp1.tEx_lm - Geometry: geom1 - Boundaries: 2, 31 Failed to evaluate Jacobian of expression. - Expression: -comp1.tEx_lm Failed to evaluate Jacobian of expression. - Expression: ((comp1.tEx-comp1.ewfd.PortConstrx)test(-comp1.tEx_lm))(dvol_spatial)

I think tEx_lm is Lagrange multiplier for electric field, though I have no idea how to fix it.


1 Reply Last Post 2021年5月6日 GMT-4 20:30
Robert Koslover Certified Consultant

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Posted: 4 years ago 2021年5月6日 GMT-4 20:30

Although I am not familiar with that particular variable, my best guess is you have some kind of mistake in the way you set up your model. There are so many, many possible ways to make mistakes when creating a Comsol model. I suggest you post your model to the forum, so others can check it out. One of us just might find the error.

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Scientific Applications & Research Associates (SARA) Inc.
www.comsol.com/partners-consultants/certified-consultants/sara
Although I am not familiar with that particular variable, my best guess is you have some kind of mistake in the way you set up your model. There are so many, many possible ways to make mistakes when creating a Comsol model. I suggest you post your model to the forum, so others can check it out. One of us just might find the error.

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