!>
!> ZPTTRS solves a tridiagonal system of the form
!>    A * X = B
!> using the factorization A = U**H *D* U or A = L*D*L**H computed by ZPTTRF.
!> D is a diagonal matrix specified in the vector D, U (or L) is a unit
!> bidiagonal matrix whose superdiagonal (subdiagonal) is specified in
!> the vector E, and X and B are N by NRHS matrices.
!> 

UPLO

!>          UPLO is CHARACTER*1
!>          Specifies the form of the factorization and whether the
!>          vector E is the superdiagonal of the upper bidiagonal factor
!>          U or the subdiagonal of the lower bidiagonal factor L.
!>          = 'U':  A = U**H *D*U, E is the superdiagonal of U
!>          = 'L':  A = L*D*L**H, E is the subdiagonal of L
!> 

N

!>          N is INTEGER
!>          The order of the tridiagonal matrix A.  N >= 0.
!> 

NRHS

!>          NRHS is INTEGER
!>          The number of right hand sides, i.e., the number of columns
!>          of the matrix B.  NRHS >= 0.
!> 

D

!>          D is DOUBLE PRECISION array, dimension (N)
!>          The n diagonal elements of the diagonal matrix D from the
!>          factorization A = U**H *D*U or A = L*D*L**H.
!> 

E

!>          E is COMPLEX*16 array, dimension (N-1)
!>          If UPLO = 'U', the (n-1) superdiagonal elements of the unit
!>          bidiagonal factor U from the factorization A = U**H*D*U.
!>          If UPLO = 'L', the (n-1) subdiagonal elements of the unit
!>          bidiagonal factor L from the factorization A = L*D*L**H.
!> 

B

!>          B is COMPLEX*16 array, dimension (LDB,NRHS)
!>          On entry, the right hand side vectors B for the system of
!>          linear equations.
!>          On exit, the solution vectors, X.
!> 

LDB

!>          LDB is INTEGER
!>          The leading dimension of the array B.  LDB >= max(1,N).
!> 

INFO

!>          INFO is INTEGER
!>          = 0: successful exit
!>          < 0: if INFO = -k, the k-th argument had an illegal value
!> 

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