Level-based Incomplete LU Factorization: Graph Model and Algorithms
نویسندگان
چکیده
A graph theoretic process that models level-based, incomplete LU factorization (ILU(`)) of sparse unsymmetric matrices is developed. The model leads to two incomplete fill path theorems that are generalizations of the original fill path theorem of Rose, Tarjan, and Lueker. Our S-level incomplete fill path theorem leads to the development of new, embarrassingly parallel algorithms for computing the structure and storage requirements of ILU(`) factors.
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