```    Program f07bgfe

!     F07BGF Example Program Text

!     Mark 25 Release. NAG Copyright 2014.

!     .. Use Statements ..
Use nag_library, Only: dgbcon, dgbtrf, dlangb => f06rbf, nag_wp, x02ajf
!     .. Implicit None Statement ..
Implicit None
!     .. Parameters ..
Integer, Parameter               :: nin = 5, nout = 6
Character (1), Parameter         :: norm = '1'
!     .. Local Scalars ..
Real (Kind=nag_wp)               :: anorm, rcond
Integer                          :: i, info, j, k, kl, ku, ldab, n
!     .. Local Arrays ..
Real (Kind=nag_wp), Allocatable  :: ab(:,:), work(:)
Integer, Allocatable             :: ipiv(:), iwork(:)
!     .. Intrinsic Procedures ..
Intrinsic                        :: max, min
!     .. Executable Statements ..
Write (nout,*) 'F07BGF Example Program Results'
!     Skip heading in data file
Read (nin,*) n, kl, ku
ldab = 2*kl + ku + 1
Allocate (ab(ldab,n),work(3*n),ipiv(n),iwork(n))

!     Read A from data file

k = kl + ku + 1

!     Compute norm of A
!     f06rbf is the NAG name equivalent of the LAPACK auxiliary dlangb
anorm = dlangb(norm,n,kl,ku,ab(kl+1,1),ldab,work)

!     Factorize A

!     The NAG name equivalent of dgbtrf id f07bdf
Call dgbtrf(n,n,kl,ku,ab,ldab,ipiv,info)

Write (nout,*)
If (info==0) Then

!       Estimate condition number

!       The NAG name equivalent of dgbcon is f07bgf
Call dgbcon(norm,n,kl,ku,ab,ldab,ipiv,anorm,rcond,work,iwork,info)

If (rcond>=x02ajf()) Then
Write (nout,99999) 'Estimate of condition number =', &
1.0_nag_wp/rcond
Else
Write (nout,*) 'A is singular to working precision'
End If
Else
Write (nout,*) 'The factor U is singular'
End If

99999 Format (1X,A,1P,E10.2)
End Program f07bgfe
```