PDDTTRSV(3)   ScaLAPACK routine of NEC Numeric Library Collection  PDDTTRSV(3)



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 routine               31 October 2017                    PDDTTRSV(3)