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come across such a problem

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I use the PDEs module to make simulation of my model, but I just encountered with a few problems of which is

undifined value in the stiffness matrix. I make sure that I have already defined all the dependent variables, but the software

point out that

"Undefined value found in the stiffness matrix.

There are 2001 equations giving NaN/Inf in the matrix rowsfor the variable mod1.ne at coordinates : (0), (5e-7), (1e-

006), (1.5e-006), (2e-006), …

There are 2001 equations giving NaN/Inf in the matrix rowsfor the variable mod1.ni at coordinates : (0), (5e-7), (1e-

006), (1.5e-006), (2e-006), …

and similarly for the degrees of freedom, NaN/Inf in the matrix columns. "

The mod1.ne and mod1.ni are the dependent variables. I don't understand the NaN/Inf and don't have any thought of

the problem I came across. Much thanks for your help!




3 Replies Last Post 30 août 2012, 21:09 UTC−4

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Posted: 1 decade ago 29 août 2012, 22:45 UTC−4
Hi, fridens! Can you give me a hand, please?
Hi, fridens! Can you give me a hand, please?

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Posted: 1 decade ago 30 août 2012, 05:52 UTC−4
Hi,


Yours is too general a question.

If you do a search in this forum for "undefined value", you will find more than 50 entries. Perhaps first just look at those to understand where you might have gone wrong.

Or alternatively, try posting your mph, to see if you get help.


Suresh
Hi, Yours is too general a question. If you do a search in this forum for "undefined value", you will find more than 50 entries. Perhaps first just look at those to understand where you might have gone wrong. Or alternatively, try posting your mph, to see if you get help. Suresh

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Posted: 1 decade ago 30 août 2012, 21:09 UTC−4
Dear Suresh,


Thanks a lot for your help! I was just confused of that for the solution.




Best regards,

venus
Dear Suresh, Thanks a lot for your help! I was just confused of that for the solution. Best regards, venus

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