Compressed Threshold Pivoting for Sparse Symmetric Indefinite Systems
نویسندگان
چکیده
منابع مشابه
Compressed threshold pivoting for sparse symmetric indefinite systems
A key technique for controlling numerical stability in sparse direct solvers is threshold partial pivoting. When selecting a pivot, the entire candidate pivot column below the diagonal must be up-to-date and must be scanned. If the factorization is parallelized across a large number of cores, communication latencies can be the dominant computational cost. In this paper, we propose two alternati...
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The performance of a sparse direct solver is dependent upon the pivot sequence that is chosen during the analyse phase. In the case of symmetric indefinite systems, it may be necessary to modify this sequence during the factorization to ensure numerical stability. Delaying pivots can have serious consequences in terms of time as well as the memory and flops required for the factorization and su...
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ژورنال
عنوان ژورنال: SIAM Journal on Matrix Analysis and Applications
سال: 2014
ISSN: 0895-4798,1095-7162
DOI: 10.1137/130920629