Provided by: scalapack-doc_1.5-11_all
NAME
PZDBTRF - compute a LU factorization of an N-by-N complex banded diagonally dominant-like distributed matrix with bandwidth BWL, BWU
SYNOPSIS
SUBROUTINE PZDBTRF( N, BWL, BWU, A, JA, DESCA, AF, LAF, WORK, LWORK, INFO ) INTEGER BWL, BWU, INFO, JA, LAF, LWORK, N INTEGER DESCA( * ) COMPLEX*16 A( * ), AF( * ), WORK( * )
PURPOSE
PZDBTRF computes a LU factorization of an N-by-N complex 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 in subsequent calls to PZDBTRS 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.