!>
!> DGTT02 computes the residual for the solution to a tridiagonal
!> system of equations:
!>    RESID = norm(B - op(A)*X) / (norm(op(A)) * norm(X) * EPS),
!> where EPS is the machine epsilon.
!> The norm used is the 1-norm.
!> 

TRANS

!>          TRANS is CHARACTER
!>          Specifies the form of the residual.
!>          = 'N':  B - A    * X  (No transpose)
!>          = 'T':  B - A**T * X  (Transpose)
!>          = 'C':  B - A**H * X  (Conjugate transpose = Transpose)
!> 

N

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

NRHS

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

DL

!>          DL is DOUBLE PRECISION array, dimension (N-1)
!>          The (n-1) sub-diagonal elements of A.
!> 

D

!>          D is DOUBLE PRECISION array, dimension (N)
!>          The diagonal elements of A.
!> 

DU

!>          DU is DOUBLE PRECISION array, dimension (N-1)
!>          The (n-1) super-diagonal elements of A.
!> 

X

!>          X is DOUBLE PRECISION array, dimension (LDX,NRHS)
!>          The computed solution vectors X.
!> 

LDX

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

B

!>          B is DOUBLE PRECISION array, dimension (LDB,NRHS)
!>          On entry, the right hand side vectors for the system of
!>          linear equations.
!>          On exit, B is overwritten with the difference B - op(A)*X.
!> 

LDB

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

RESID

!>          RESID is DOUBLE PRECISION
!>          norm(B - op(A)*X) / (norm(op(A)) * norm(X) * EPS)
!> 

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