Schur complement system

[Lisandro Dalcin]

On 3/10/08, Matthew Knepley <knepley at gmail.com> wrote:
> By 4 matrices, I assume you mean A, B, C where
>
>   S = B^T A^{-1} B + C
>
>  right?

Yes, but actually four matrices, [[A_II, A_IB], [A_BI, A_BB]], were

S = (A_BB - A_BI * A_II^{-1} * A_IB)

'B' are interface nodes and 'I' are interior nodes. The operator does
not need to be symmetric.

However, I have the strong feeling (from therory as well as practice)
that my implementation is not actually better than ASM, except for the
fact that I'm iterating over interface nodes only. I need to work a
bit on ASM to enable partitioning subdomains (or use the support for
setting local subdomain indices) to experiment and be completely sure
about this.

-- 
Lisandro Dalcín
---------------
Centro Internacional de Métodos Computacionales en Ingeniería (CIMEC)
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