Program f16rbfe

!     F16RBF Example Program Text

!     Mark 30.1 Release. NAG Copyright 2024.

!     .. Use Statements ..
      Use nag_library, Only: f01zcf, f16rbf, nag_frobenius_norm, nag_inf_norm, &
                             nag_max_norm, nag_one_norm, nag_wp
!     .. Implicit None Statement ..
      Implicit None
!     .. Parameters ..
      Integer, Parameter               :: nin = 5, nout = 6
!     .. Local Scalars ..
      Real (Kind=nag_wp)               :: r_fro, r_inf, r_max, r_one
      Integer                          :: i, ifail, j, kl, ku, lda, ldab, m, n
      Character (1)                    :: job
!     .. Local Arrays ..
      Real (Kind=nag_wp), Allocatable  :: a(:,:), ab(:,:)
!     .. Intrinsic Procedures ..
      Intrinsic                        :: max, min
!     .. Executable Statements ..
      Write (nout,*) 'F16RBF Example Program Results'

!     Skip heading in data file
      Read (nin,*)

      Read (nin,*) m, n, kl, ku
      lda = m
      ldab = kl + ku + 1
      Allocate (a(lda,n),ab(ldab,n))

!     Read A from data file into rectangular storage

      Do i = 1, m
        Read (nin,*)(a(i,j),j=max(1,i-kl),min(n,i+ku))
      End Do

!     Convert A to packed storage

      job = 'P'

      ifail = 0
      Call f01zcf(job,m,n,kl,ku,a,lda,ab,ldab,ifail)

      Write (nout,*)
      Write (nout,99999) 'Norms of banded matrix AB:'
      Write (nout,*)

      r_one = f16rbf(nag_one_norm,m,n,kl,ku,ab,ldab)
      Write (nout,99998) 'One norm           = ', r_one

      r_inf = f16rbf(nag_inf_norm,m,n,kl,ku,ab,ldab)
      Write (nout,99998) 'Infinity norm      = ', r_inf

      r_fro = f16rbf(nag_frobenius_norm,m,n,kl,ku,ab,ldab)
      Write (nout,99998) 'Frobenius norm     = ', r_fro

      r_max = f16rbf(nag_max_norm,m,n,kl,ku,ab,ldab)
      Write (nout,99998) 'Maximum norm       = ', r_max

99999 Format (1X,A)
99998 Format (1X,A,F9.4)
    End Program f16rbfe