Program e04nfae

!     E04NFA Example Program Text

!     Mark 30.1 Release. NAG Copyright 2024.

!     .. Use Statements ..
      Use nag_library, Only: e04nfa, e04wbf, e54nfu, nag_wp
!     .. Implicit None Statement ..
      Implicit None
!     .. Parameters ..
      Integer, Parameter               :: lcwsav = 1, liwsav = 610,            &
                                          llwsav = 120, lrwsav = 475, nin = 5, &
                                          nout = 6
!     .. Local Scalars ..
      Real (Kind=nag_wp)               :: obj
      Integer                          :: i, ifail, iter, j, lda, ldh, liwork, &
                                          lwork, n, nclin, sda
!     .. Local Arrays ..
      Real (Kind=nag_wp), Allocatable  :: a(:,:), ax(:), bl(:), bu(:),         &
                                          clamda(:), cvec(:), h(:,:), work(:), &
                                          x(:)
      Real (Kind=nag_wp)               :: ruser(1), rwsav(lrwsav)
      Integer, Allocatable             :: istate(:), iwork(:)
      Integer                          :: iwsav(liwsav)
      Logical                          :: lwsav(llwsav)
      Character (80)                   :: cwsav(lcwsav)
!     .. Intrinsic Procedures ..
      Intrinsic                        :: max
!     .. Executable Statements ..
      Write (nout,*) 'E04NFA Example Program Results'

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

      Read (nin,*) n, nclin
      liwork = 2*n + 3
      lda = max(1,nclin)

      If (nclin>0) Then
        sda = n
      Else
        sda = 1
      End If

!     This particular example problem is of type QP2 with H stored explicitly,
!     so we allocate CVEC(N) and H(LDH,N), and define LDH and LWORK as below

      ldh = n

      If (nclin>0) Then
        lwork = 2*n**2 + 8*n + 5*nclin
      Else
        lwork = n**2 + 8*n
      End If

      Allocate (istate(n+nclin),ax(max(1,nclin)),iwork(liwork),h(ldh,n),bl(n+  &
        nclin),bu(n+nclin),cvec(n),x(n),a(lda,sda),clamda(n+nclin),            &
        work(lwork))

      Read (nin,*) cvec(1:n)
      Read (nin,*)(a(i,1:sda),i=1,nclin)
      Read (nin,*) bl(1:(n+nclin))
      Read (nin,*) bu(1:(n+nclin))
      Read (nin,*) x(1:n)
      Read (nin,*)(h(i,1:n),i=1,n)

!     Initialise E04NFA

      ifail = 0
      Call e04wbf('E04NFA',cwsav,lcwsav,lwsav,llwsav,iwsav,liwsav,rwsav,       &
        lrwsav,ifail)

!     Solve the problem

      ifail = -1
      Call e04nfa(n,nclin,a,lda,bl,bu,cvec,h,ldh,e54nfu,istate,x,iter,obj,ax,  &
        clamda,iwork,liwork,work,lwork,iwsav,ruser,lwsav,iwsav,rwsav,ifail)

      Select Case (ifail)
      Case (0:5,7:)
        Write (nout,*)
        Write (nout,99999)
        Write (nout,*)

        Do i = 1, n
          Write (nout,99998) i, istate(i), x(i), clamda(i)
        End Do

        If (nclin>0) Then
          Write (nout,*)
          Write (nout,*)
          Write (nout,99997)
          Write (nout,*)

          Do i = n + 1, n + nclin
            j = i - n
            Write (nout,99996) j, istate(i), ax(j), clamda(i)
          End Do

        End If

        Write (nout,*)
        Write (nout,*)
        Write (nout,99995) obj
        Write (nout,*)
        Write (nout,*)
        Write (nout,99994) iter
      End Select

99999 Format (1X,'Varbl',2X,'Istate',3X,'Value',9X,'Lagr Mult')
99998 Format (1X,'V',2(1X,I3),4X,1P,G14.6,2X,1P,G12.4)
99997 Format (1X,'L Con',2X,'Istate',3X,'Value',9X,'Lagr Mult')
99996 Format (1X,'L',2(1X,I3),4X,1P,G14.6,2X,1P,G12.4)
99995 Format (1X,'Final objective value = ',G15.7)
99994 Format (1X,'Exit from problem after',1X,I6,1X,'iterations.')
    End Program e04nfae