```    Program f08gafe

!     F08GAF Example Program Text

!     Mark 26.1 Release. NAG Copyright 2017.

!     .. Use Statements ..
Use nag_library, Only: dspev, nag_wp, x02ajf
!     .. Implicit None Statement ..
Implicit None
!     .. Parameters ..
Integer, Parameter               :: nin = 5, nout = 6
Character (1), Parameter         :: uplo = 'U'
!     .. Local Scalars ..
Real (Kind=nag_wp)               :: eerrbd, eps
Integer                          :: i, info, j, n
!     .. Local Arrays ..
Real (Kind=nag_wp), Allocatable  :: ap(:), w(:), work(:)
Real (Kind=nag_wp)               :: dummy(1,1)
!     .. Intrinsic Procedures ..
Intrinsic                        :: abs, max
!     .. Executable Statements ..
Write (nout,*) 'F08GAF Example Program Results'
Write (nout,*)
!     Skip heading in data file

Allocate (ap((n*(n+1))/2),w(n),work(3*n))

!     Read the upper or lower triangular part of the matrix A from
!     data file

If (uplo=='U') Then
Else If (uplo=='L') Then
End If

!     Solve the symmetric eigenvalue problem
!     The NAG name equivalent of dspev is f08gaf
Call dspev('No vectors',uplo,n,ap,w,dummy,1,work,info)

If (info==0) Then

!       Print solution

Write (nout,*) 'Eigenvalues'
Write (nout,99999) w(1:n)

!       Get the machine precision, EPS and compute the approximate
!       error bound for the computed eigenvalues.  Note that for
!       the 2-norm, max( abs(W(i)) ) = norm(A), and since the
!       eigenvalues are returned in ascending order
!       max( abs(W(i)) ) = max( abs(W(1)), abs(W(n)))

eps = x02ajf()
eerrbd = eps*max(abs(w(1)),abs(w(n)))

!       Print the approximate error bound for the eigenvalues

Write (nout,*)
Write (nout,*) 'Error estimate for the eigenvalues'
Write (nout,99998) eerrbd
Else
Write (nout,99997) 'Failure in DSPEV. INFO =', info
End If

99999 Format (3X,(8F8.4))
99998 Format (4X,1P,6E11.1)
99997 Format (1X,A,I4)
End Program f08gafe
```