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MiS Preprint
64/2001
An efficient direct solver for the boundary concentrated FEM in 2D
Boris N. Khoromskij and Jens Markus Melenk
Abstract
The boundary concentrated FEM, a variant of the hp-version of the finite element method, is proposed for the numerical treatment of elliptic boundary value problems. It is particularly suited for equations with smooth coefficients and boundary conditions that may have low Sobolev regularity. In the two-dimensional case, it is shown that the Cholesky factorization of the resulting stiffness matrix requires O( N log4N) units of storage and can be computed with O( N log8N) work. Numerical results confirm theoretical estimates.
