Null Space Algorithms for Solving Augmented Systems arising in the Mixed Finite Element Approximation of Saddle Point Problems
نویسندگان
چکیده
We use a Null Space algorithm approach to solve augmented systems produced by the mixed finite element approximation of saddle point problems. We compare the use of an orthogonal factorization technique for sparse matrices with the use of a sparse Gaussian elimination for the computation of the Null Space. Finally, we present the results of the numerical tests which we performed on selected problems. Key-words: Augmented Systems, Sparse Matrices, Mixed Finite Elements.
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