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pddbtrf
Langue: en
Version: 286463 (debian - 07/07/09)
Section: 3 (Bibliothèques de fonctions)
NAME
PDDBTRF - compute a LU factorization of an N-by-N real banded diagonally dominant-like distributed matrix with bandwidth BWL, BWUSYNOPSIS
- SUBROUTINE PDDBTRF(
- N, BWL, BWU, A, JA, DESCA, AF, LAF, WORK, LWORK, INFO )
- INTEGER BWL, BWU, INFO, JA, LAF, LWORK, N
- INTEGER DESCA( * )
- DOUBLE PRECISION A( * ), AF( * ), WORK( * )
PURPOSE
PDDBTRF computes a LU factorization of an N-by-N real banded diagonally dominant-like distributed matrix with bandwidth BWL, BWU: A(1:N, JA:JA+N-1). Reordering is used to increase parallelism in the factorization. This reordering results in factors that are DIFFERENT from those produced by equivalent sequential codes. These factors cannot be used directly by users; however, they can be used insubsequent calls to PDDBTRS to solve linear systems.
The factorization has the form
P A(1:N, JA:JA+N-1) P^T = L U
where U is a banded upper triangular matrix and L is banded lower triangular, and P is a permutation matrix.
Contenus ©2006-2024 Benjamin Poulain
Design ©2006-2024 Maxime Vantorre