Provided by: scalapack-doc_1.5-10_all
NAME
PCDBTRSV - solve a banded triangular system of linear equations A(1:N, JA:JA+N-1) * X = B(IB:IB+N-1, 1:NRHS)
SYNOPSIS
SUBROUTINE PCDBTRSV( UPLO, TRANS, N, BWL, BWU, NRHS, A, JA, DESCA, B, IB, DESCB, AF, LAF, WORK, LWORK, INFO ) CHARACTER TRANS, UPLO INTEGER BWL, BWU, IB, INFO, JA, LAF, LWORK, N, NRHS INTEGER DESCA( * ), DESCB( * ) COMPLEX A( * ), AF( * ), B( * ), WORK( * )
PURPOSE
PCDBTRSV solves a banded triangular system of linear equations or A(1:N, JA:JA+N-1)^H * X = B(IB:IB+N-1, 1:NRHS) where A(1:N, JA:JA+N-1) is a banded triangular matrix factor produced by the Gaussian elimination code PC@(dom_pre)BTRF and is stored in A(1:N,JA:JA+N-1) and AF. The matrix stored in A(1:N, JA:JA+N-1) is either upper or lower triangular according to UPLO, and the choice of solving A(1:N, JA:JA+N-1) or A(1:N, JA:JA+N-1)^H is dictated by the user by the parameter TRANS. Routine PCDBTRF MUST be called first.