DragonFly On-Line Manual Pages

PDDTTRSV(l)                            )                           PDDTTRSV(l)

NAME
       PDDTTRSV - solve a tridiagonal triangular system of linear equations
       A(1:N, JA:JA+N-1) * X = B(IB:IB+N-1, 1:NRHS)

SYNOPSIS
       SUBROUTINE PDDTTRSV( UPLO, TRANS, N, NRHS, DL, D, DU, JA, DESCA, B, IB,
                            DESCB, AF, LAF, WORK, LWORK, INFO )
           CHARACTER TRANS, UPLO
           INTEGER IB, INFO, JA, LAF, LWORK, N, NRHS
           INTEGER DESCA( * ), DESCB( * )
           DOUBLE PRECISION AF( * ), B( * ), D( * ), DL( * ), DU( * ), WORK( *
       )

PURPOSE
       PDDTTRSV solves a tridiagonal triangular system of linear equations
       A(1:N, JA:JA+N-1) * X = B(IB:IB+N-1, 1:NRHS)
       or
                           A(1:N, JA:JA+N-1)^T * X = B(IB:IB+N-1, 1:NRHS)

       where A(1:N, JA:JA+N-1) is a tridiagonal
       triangular matrix factor produced by the
       Gaussian elimination code PD@(dom_pre)TTRF
       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)^T is
       dictated by the user by the parameter TRANS.

       Routine PDDTTRF MUST be called first.

ScaLAPACK version 1.7           13 August 2001                     PDDTTRSV(l)