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How to get the stiffness matrix without computing the whole solution?

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Hey,

I am a student major in geo-engineering and recently I am stuck with a Livelink for Matlab problem.
As for a subsurface seepage flow problem, the default solver of Comsol seems very hard to converge to the exact solution.

So I want to use my own algorithm in Matlab together with the finite element data assembled by Comsol to solve the problem.

Then I convert my model to .m file and recreate the model in Comsol within Matlab without running the default solver as it will never converge, and I create an "Assemble" feature "a1" to get the finite element data.

BUT I find it impossible by using matlab code "model.sol('sol1').feature('a1').getSparseMatrixVal('K')" to get the initial stiffness matrix of the model just because it is not computed!

Does anyone know how to get this problem done?

0 Replies Last Post Oct 26, 2015, 10:30 a.m. EDT
COMSOL Moderator

Hello Jason Leung

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