Solve a tridiagonal triangular system of linear equations a(1:n, ja:ja+n-1) * x = b(ib:ib+n-1, 1:nrhs)
SUBROUTINE PZDTTRSV(
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( * )
COMPLEX*16
AF( * ), B( * ), D( * ), DL( * ), DU( * ), WORK( * )
PZDTTRSV 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
Gaussian elimination code PZ@(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)^H is dictated by the user by the parameter TRANS.
Routine PZDTTRF MUST be called first.