Two improved algorithms for envelope and wavefront reduction
نویسندگان
چکیده
منابع مشابه
Two Improved Algorithms for Envelope and Wavefront Reduction
Two algorithms for reordering sparse, symmetric matrices or undirected graphs to reduce envelope and wavefront are considered. The first is a combinatorial algorithm introduced by Sloan and further developed by Duff, Reid, and Scott; we describe enhancements to the Sloan algorithm that improve its quality and reduce its run time. Our test problems fall into two classes with differing asymptotic...
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Multilevel algorithms are proposed for reordering sparse symmetric matrices to reduce the wavefront and proole. A graph representation of the matrix is used and two graph coarsening methods are investigated. A multilevel algorithm that uses a maximal independent vertex set for coarsening and the Sloan algorithm on the coarsest graph is shown to produce orderings that are of a similar quality to...
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ژورنال
عنوان ژورنال: BIT Numerical Mathematics
سال: 1997
ISSN: 0006-3835,1572-9125
DOI: 10.1007/bf02510240