Detecting ill-condition matrix in PARDISO (instability in FE model)

Alemdar__Bulent — Fri, 30 May 2008 00:34:25 GMT

We are planning to use PARDISO in out finite element analysis package. Usually the matrix to be solved is positive-deifinite symmetric matrix. But sometimes, wemight haveill-conditioned matrix (this might be due to mesh discretization error or any unsupressed rigid body mode in our finite element model). If this is the case, we try to extract node (or the position of diagonal term that leads to negative pivoting) and then we check our FE model at this node to make any correction in our model.

I tried a few examples in PARDISO, and once it fails to solve the system but I coudn't find any more information returned by the solver.

Is there any way to get more info from the solver like node or diagonal number if PARDISO fails to solve an ill-conditioned matrix?

best regards

bulent

Re: Detecting ill-condition matrix in PARDISO (instability in F

Sergey_K_Intel1 — Sat, 07 Jun 2008 13:21:26 GMT

Dear Bulent,

At the present PARDISO doesn't returm the position of zero diagonalelement for ill-conditioned or singular matrices. We have plans to implement the feature in one of future releases.

All the best

Sergey

topic Detecting ill-condition matrix in PARDISO (instability in FE model) in Intel® oneAPI Math Kernel Library

Detecting ill-condition matrix in PARDISO (instability in FE model)

Re: Detecting ill-condition matrix in PARDISO (instability in F