Does Lapack have a solver for banded, symmetric, but not positive definite matrix?

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Mohamed-Mourad Lafifi

Dear Igor Ravve,

I suggest you to see links and attached fies on topic.

https://cvxopt.org/userguide/lapack.html

https://cvxopt.org/userguide/intro.html

https://cvxopt.readthedocs.io/en/latest/

Best regards

Peter Spellucci

would make little sense, since in case of nonpositive definiteness pivoting

would be necessary anyway for guaranteeing stability, and e.g. a symmetric

but non positive definite decomposition (like bunch-parlett) would by far

destroy sparsity.