!>
!> SPBT02 computes the residual for a solution of a symmetric banded
!> system of equations  A*x = b:
!>    RESID = norm( B - A*X ) / ( norm(A) * norm(X) * EPS)
!> where EPS is the machine precision.
!> 

UPLO

!>          UPLO is CHARACTER*1
!>          Specifies whether the upper or lower triangular part of the
!>          symmetric matrix A is stored:
!>          = 'U':  Upper triangular
!>          = 'L':  Lower triangular
!> 

N

!>          N is INTEGER
!>          The number of rows and columns of the matrix A.  N >= 0.
!> 

KD

!>          KD is INTEGER
!>          The number of super-diagonals of the matrix A if UPLO = 'U',
!>          or the number of sub-diagonals if UPLO = 'L'.  KD >= 0.
!> 

NRHS

!>          NRHS is INTEGER
!>          The number of right hand sides. NRHS >= 0.
!> 

A

!>          A is REAL array, dimension (LDA,N)
!>          The original symmetric band matrix A.  If UPLO = 'U', the
!>          upper triangular part of A is stored as a band matrix; if
!>          UPLO = 'L', the lower triangular part of A is stored.  The
!>          columns of the appropriate triangle are stored in the columns
!>          of A and the diagonals of the triangle are stored in the rows
!>          of A.  See SPBTRF for further details.
!> 

LDA

!>          LDA is INTEGER.
!>          The leading dimension of the array A.  LDA >= max(1,KD+1).
!> 

X

!>          X is REAL array, dimension (LDX,NRHS)
!>          The computed solution vectors for the system of linear
!>          equations.
!> 

LDX

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

B

!>          B is REAL 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 - A*X.
!> 

LDB

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

RWORK

!>          RWORK is REAL array, dimension (N)
!> 

RESID

!>          RESID is REAL
!>          The maximum over the number of right hand sides of
!>          norm(B - A*X) / ( norm(A) * norm(X) * EPS ).
!> 

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