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37 lines
2.1 KiB
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37 lines
2.1 KiB
Plaintext
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UMFPACK Version 2.2 is a package for solving systems of sparse linear systems,
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Ax=b, where A is sparse and can be unsymmetric. It is written in ANSI Fortran
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77. There are options for choosing a good pivot order, factorizing a
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subsequent matrix with the same pivot order and nonzero pattern as a
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previously factorized matrix, and solving systems of linear equations with
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the factors (with A, L, or U; or with their transposes in the single/double
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precision versions). Iterative refinement, with sparse backward error
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estimates, can be performed. Single and double precision, complex, and
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complex double precision (complex*16) routines are available. (Note that
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complex*16 is not ANSI Fortran-77, but is a common extension to it).
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For more information
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--------------------
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For more information, see T. A. Davis and I. S. Duff, "An
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unsymmetric-pattern multifrontal method for sparse LU factorization",
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SIAM J. Matrix Analysis and Applications (to appear), also
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technical report TR-94-038, CISE Dept., Univ. of Florida,
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P.O. Box 116120, Gainesville, FL 32611-6120, USA. The method used
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here is a modification of that method, described in T. A. Davis,
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"A combined unifrontal/multifrontal method for unsymmetric sparse
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matrices," TR-94-005, and in T. A. Davis and I. S. Duff, (same title),
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TR-95-020. (Technical reports are available via WWW at
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http://www.cis.ufl.edu/). The (unsymmetric) approximate degree update
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algorithm used here has been incorporated into a symmetric approximate
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minimum degree ordering algorithm, described in P. Amestoy, T. A. Davis,
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and I. S. Duff, "An approximate minimum degree ordering algorithm",
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SIAM Journal on Matrix Analysis and Applications (to appear, also TR-94-039).
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The approximate minimum degree ordering algorithm is implemented as MC47
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in the Harwell Subroutine Library (MC47 is not used in UMFPACK).
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Also take a look at our World Wide Web home pages:
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Tim Davis: http://www.cis.ufl.edu/~davis
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(also email: davis@cis.ufl.edu).
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Iain Duff: http://www.cis.rl.ac.uk/people/isd/contact.html
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______________
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Timothy A. Davis and Iain S. Duff. Copyright (C) 1997.
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