a simple question

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liufeng19
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Joined: Sat Dec 16, 2006 6:01 am
Location: Tongji university, in China

a simple question

Post by liufeng19 »

what is the meaning of "WARNING BandGenLinLapackSolver::solve<> -LAPACK routine returned 1", after i run the program? how to solve the problem of convergence like this?
fmk
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Post by fmk »

it indicates a problem with the matrix .. which,
given the fact you are using a banded general, probably means you have a singular matrix ..
if this is occuring in the first step it means you don't have enough constraints, if during an analysis which was working and suddenly stops with this error it also means a rigid body mode, however in this case you can see what iterating with some initial stiffness iterations might do.
liufeng19
Posts: 10
Joined: Sat Dec 16, 2006 6:01 am
Location: Tongji university, in China

Post by liufeng19 »

thank you very very much!!
liufeng19
Posts: 10
Joined: Sat Dec 16, 2006 6:01 am
Location: Tongji university, in China

Post by liufeng19 »

what is the so-called rigid body mode? is that caused by usage of rigidLink in model?
silvia
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Post by silvia »

it means you do not have enough constraints in your model.
Silvia Mazzoni, PhD
Structural Consultant
Degenkolb Engineers
235 Montgomery Street, Suite 500
San Francisco, CA. 94104
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