NAG Library Manual, Mark 27.2
```    Program x04dffe

!     X04DFF Example Program Text

!     Mark 27.2 Release. NAG Copyright 2021.

!     .. Use Statements ..
Use nag_library, Only: f01zdf, nag_wp, x04dff
!     .. Implicit None Statement ..
Implicit None
!     .. Parameters ..
Integer, Parameter               :: n = 5, nout = 6
Character (7), Parameter         :: clabs(n) = (/'Un     ','Deux   ',    &
'Trois  ','Quatre ','Cinq   '/)
Character (7), Parameter         :: rlabs(n) = (/'Uno    ','Due    ',    &
'Tre    ','Quattro','Cinque '/)
!     .. Local Scalars ..
Real (Kind=nag_wp)               :: aa
Integer                          :: i, ifail, indent, j, kl, ku, ku_a,   &
lda, ldab, m, ncols
Character (19)                   :: form
Character (1)                    :: job
!     .. Local Arrays ..
Complex (Kind=nag_wp), Allocatable :: a(:,:), ab(:,:)
!     .. Intrinsic Procedures ..
Intrinsic                        :: cmplx, max, min, real
!     .. Executable Statements ..
Write (nout,*) 'X04DFF Example Program Results'

Write (nout,*)
Flush (nout)

!     Generate a square array of data.

m = n
kl = 1
ku_a = 2

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

Do j = 1, n

Do i = max(1,j-ku_a), min(m,j+kl)
aa = real(10*i+j,kind=nag_wp)
a(i,j) = cmplx(aa,-aa,kind=nag_wp)
End Do

End Do

!     Convert a to packed storage, ignoring the second superdiagonal.

ldab = kl + ku_a + 1
Allocate (ab(ldab,n))

ku = 1

job = 'P'

ifail = 0
Call f01zdf(job,m,n,kl,ku,a,lda,ab,ldab,ifail)

ncols = 80
indent = 0

!     Print m by n band matrix with kl subdiagonals, 1 superdiagonal,
!     default format, bracketed complex numbers, and integer row and
!     column labels

form = ' '

ifail = 0
Call x04dff(m,n,kl,1,ab,ldab,'Bracketed',form,'Example 1:','Integer',    &
rlabs,'Integer',clabs,ncols,indent,ifail)

Write (nout,*)
Flush (nout)

!     Convert the whole matrix a to packed storage.

ku = ku_a

job = 'P'

ifail = 0
Call f01zdf(job,m,n,kl,ku,a,lda,ab,ldab,ifail)

!     Print (m-1) by (n-1) band matrix with kl subdiagonals,
!     ku superdiagonals, user-supplied format and row and column labels.

form = 'SS,F7.1,SP,F6.1,''i'''

ifail = 0
Call x04dff(m-1,n-1,kl,ku,ab,ldab,'Direct',form,'Example 2:',            &
'Character',rlabs,'Character',clabs,ncols,indent,ifail)

Write (nout,*)
Flush (nout)

!     Print (m-1) by (n-1) band matrix with kl subdiagonals,
!     ku superdiagonals, in MATLAB format.
!     Row and column labelling and USEFRM are ignored.

form = 'MATLABF7.1'

ifail = 0
Call x04dff(m-1,n-1,kl,ku,ab,ldab,' ',form,'A',' ',rlabs,' ',clabs,      &
ncols,indent,ifail)

End Program x04dffe
```