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PSPTTRSV(l)                            )                           PSPTTRSV(l)

NAME
       PSPTTRSV - 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 PSPTTRSV( UPLO, N, NRHS, D, E, JA, DESCA, B, IB, DESCB, AF,
                            LAF, WORK, LWORK, INFO )
           CHARACTER UPLO
           INTEGER IB, INFO, JA, LAF, LWORK, N, NRHS
           INTEGER DESCA( * ), DESCB( * )
           REAL AF( * ), B( * ), D( * ), E( * ), WORK( * )

PURPOSE
       PSPTTRSV 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
       Cholesky factorization code PSPTTRF
       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 PSPTTRF MUST be called first.

ScaLAPACK version 1.7           13 August 2001                     PSPTTRSV(l)