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Errors "JavaNullPointer" when inputting matrix with multigrid preconditioner

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Hi everyone, I'm using Livelink(TM) for Matlab(R). When I tried to run the solution after inputting matrix to an electrostatic model's stationary solver, the error came out with "java.lang.NullPointerException" and the server flashes and disappeared. I've checked a few settings and found that it was probably about the multigrid preconditioner. I think the InputMatrix node cannot work well if the stationary solver uses multigrid preconditioner. But why? Can anyone tell me? How can I solve this problem?

The picture below is the example commands I use. Maybe help understand.

So much thanks

Fei



1 Reply Last Post Jul 11, 2019, 7:37 a.m. EDT
Jesper Been COMSOL Employee

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Posted: 5 years ago Jul 11, 2019, 7:37 a.m. EDT
Updated: 5 years ago Jul 11, 2019, 7:35 a.m. EDT

Hi,

I just did quick test and couldn't repeat the error, but without your model it isn't really conclusive. I recommend that you update COMSOL to the newest version and if that doesn't change anything contact Support.

Best Regards, Jesper Been COMSOL

Hi, I just did quick test and couldn't repeat the error, but without your model it isn't really conclusive. I recommend that you update COMSOL to the newest version and if that doesn't change anything contact Support. Best Regards, Jesper Been COMSOL

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