Solve a system of linear equations a(1:n, ja:ja+n-1) * x = b(ib:ib+n-1, 1:nrhs)
SUBROUTINE PZPTTRS(
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( * )
COMPLEX*16
AF( * ), B( * ), E( * ), WORK( * )
DOUBLE
PRECISION D( * )
PZPTTRS solves a system of linear equations
where A(1:N, JA:JA+N-1) is the matrix used to produce the factors stored in A(1:N,JA:JA+N-1) and AF by PZPTTRF.
A(1:N, JA:JA+N-1) is an N-by-N complex
tridiagonal symmetric positive definite distributed
matrix.
Depending on the value of UPLO, A stores either U or L in the equn A(1:N, JA:JA+N-1) = U'D *U or L*D L' as computed by PZPTTRF.
Routine PZPTTRF MUST be called first.