NAG Library Manual, Mark 28.3
```    Program f01jafe

!     F01JAF Example Program Text

!     Mark 28.3 Release. NAG Copyright 2022.

!     .. Use Statements ..
Use nag_library, Only: f01jaf, nag_wp, x02ajf, x04caf
!     .. Implicit None Statement ..
Implicit None
!     .. Parameters ..
Integer, Parameter               :: nin = 5, nout = 6
!     .. Local Scalars ..
Real (Kind=nag_wp)               :: conda, cond_rel, eps, norma, normfa
Integer                          :: i, ifail, lda, n
Character (4)                    :: fun
!     .. Local Arrays ..
Real (Kind=nag_wp), Allocatable  :: a(:,:)
!     .. Executable Statements ..
Write (nout,*) 'F01JAF Example Program Results'
Write (nout,*)
Flush (nout)

!     Skip heading in data file

lda = n
Allocate (a(lda,n))

!     Read A from data file

!     Display A
ifail = 0
Call x04caf('G','N',n,n,a,lda,'A',ifail)

!     Find absolute condition number estimate
ifail = 0
Call f01jaf(fun,n,a,lda,conda,norma,normfa,ifail)

If (ifail==0) Then
!       Print solution
Write (nout,*)
Write (nout,*) 'F(A) = ', fun, '(A)'
Write (nout,99999) 'Estimated absolute condition number is: ', conda

!       Find relative condition number estimate
eps = x02ajf()
If (normfa>eps) Then
cond_rel = conda*norma/normfa
Write (nout,99999) 'Estimated relative condition number is: ',       &
cond_rel
Else
Write (nout,99998) 'The estimated norm of f(A) is effectively zero', &
'and so the relative condition number is undefined.'
End If
End If

99999 Format (1X,A,F7.2)
99998 Format (/,1X,A,/,1X,A)

End Program f01jafe
```