Program e02bcfe

!     E02BCF Example Program Text

!     Mark 28.4 Release. NAG Copyright 2022.

!     .. Use Statements ..
      Use nag_library, Only: e02bcf, nag_wp
!     .. Implicit None Statement ..
      Implicit None
!     .. Parameters ..
      Integer, Parameter               :: nin = 5, nout = 6
!     .. Local Scalars ..
      Real (Kind=nag_wp)               :: x
      Integer                          :: i, ifail, l, left, m, ncap, ncap7
!     .. Local Arrays ..
      Real (Kind=nag_wp), Allocatable  :: c(:), lamda(:)
      Real (Kind=nag_wp)               :: s(4)
!     .. Executable Statements ..
      Write (nout,*) 'E02BCF Example Program Results'

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

      Read (nin,*) ncap, m
      ncap7 = ncap + 7
      Allocate (lamda(ncap7),c(ncap7))

      Read (nin,*) lamda(1:ncap7)
      Read (nin,*) c(1:(ncap+3))

      Do i = 1, m
        Read (nin,*) x

        Do left = 1, 2

          ifail = 0
          Call e02bcf(ncap7,lamda,c,x,left,s,ifail)

          If (left==1) Then

            If (i==1) Then
              Write (nout,*)
              Write (nout,*)                                                   &
                '      X             Spline    1st deriv   2nd deriv   ',      &
                '3rd deriv'
            End If

            Write (nout,*)
            Write (nout,99999) x, '  LEFT', (s(l),l=1,4)
          Else
            Write (nout,99999) x, ' RIGHT', (s(l),l=1,4)
          End If

        End Do

      End Do

99999 Format (1X,E10.2,A,4E12.4)
    End Program e02bcfe