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MiS Preprint
68/2004
Hybrid Cross Approximation of Integral Operators
Steffen Börm and Lars Grasedyck
Abstract
The efficient treatment of dense matrices arising, e.g., from the finite element discretisation of integral operators, requires special compression techniques. In this article we use the ${\cal H}$-matrix representation that approximates the dense stiffness matrix in admissible blocks (corresponding to subdomains where the underlying kernel function is smooth) by low rank matrices. The low rank matrices are assembled by a new hybrid algorithm (HCA) that has the same proven convergence as standard interpolation but also the same efficiency as the (heuristic) adaptive cross approximation (ACA).
