```    Program f07fffe

!     F07FFF Example Program Text

!     Mark 27.0 Release. NAG Copyright 2019.

!     .. Use Statements ..
Use nag_library, Only: dpoequ, dscal, f06fcf, nag_wp, x02ajf, x02amf,    &
x02bhf, x04caf
!     .. Implicit None Statement ..
Implicit None
!     .. Parameters ..
Real (Kind=nag_wp), Parameter    :: one = 1.0_nag_wp
Real (Kind=nag_wp), Parameter    :: thresh = 0.1_nag_wp
Integer, Parameter               :: nin = 5, nout = 6
!     .. Local Scalars ..
Real (Kind=nag_wp)               :: amax, big, scond, small
Integer                          :: i, ifail, info, j, lda, n
!     .. Local Arrays ..
Real (Kind=nag_wp), Allocatable  :: a(:,:), s(:)
!     .. Intrinsic Procedures ..
Intrinsic                        :: real
!     .. Executable Statements ..
Write (nout,*) 'F07FFF Example Program Results'
Write (nout,*)
Flush (nout)
!     Skip heading in data file
lda = n
Allocate (a(lda,n),s(n))

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

!     Print the matrix A

!     ifail: behaviour on error exit
!             =0 for hard exit, =1 for quiet-soft, =-1 for noisy-soft
ifail = 0
Call x04caf('Upper','Non-unit',n,n,a,lda,'Matrix A',ifail)

Write (nout,*)

!     Compute diagonal scaling factors
!     The NAG name equivalent of dpoequ is f07fff
Call dpoequ(n,a,lda,s,scond,amax,info)

If (info>0) Then
Write (nout,99999) 'Diagonal element', info, ' of A is non positive'
Else

!       Print SCOND, AMAX and the scale factors

Write (nout,99998) 'SCOND =', scond, ', AMAX =', amax
Write (nout,*)
Write (nout,*) 'Diagonal scaling factors'
Write (nout,99997) s(1:n)
Write (nout,*)
Flush (nout)

!       Compute values close to underflow and overflow

small = x02amf()/(x02ajf()*real(x02bhf(),kind=nag_wp))
big = one/small
If ((scond<thresh) .Or. (amax<small) .Or. (amax>big)) Then

!         Scale A
!         The NAG name equivalent of dscal is f06edf
Do j = 1, n
Call dscal(j,s(j),a(1,j),1)
Call f06fcf(j,s,1,a(1,j),1)
End Do

!         Print the scaled matrix

ifail = 0
Call x04caf('Upper','Non-unit',n,n,a,lda,'Scaled matrix',ifail)

End If
End If

99999 Format (1X,A,I4,A)
99998 Format (1X,2(A,1P,E8.1))
99997 Format ((1X,1P,7E11.1))
End Program f07fffe
```