NAME
PCPTTRSV - 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 PCPTTRSV( UPLO, TRANS, N, NRHS, D, E, JA, DESCA, B, IB,
DESCB, AF, LAF, WORK, LWORK, INFO )
CHARACTER TRANS, UPLO
INTEGER IB, INFO, JA, LAF, LWORK, N, NRHS
INTEGER DESCA( * ), DESCB( * )
COMPLEX AF( * ), B( * ), E( * ), WORK( * )
REAL D( * )
PURPOSE
PCPTTRSV solves a tridiagonal 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 tridiagonal
triangular matrix factor produced by the
Cholesky factorization code PCPTTRF
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 PCPTTRF MUST be called first.