NAG Library Manual, Mark 30
Interfaces:  FL   CL   CPP   AD 

NAG FL Interface Introduction
Example description
    Program e04nffe

!     E04NFF Example Program Text

!     Mark 30.0 Release. NAG Copyright 2024.

!     .. Use Statements ..
      Use nag_library, Only: e04nff, e04nfu, nag_wp
!     .. Implicit None Statement ..
      Implicit None
!     .. Parameters ..
      Integer, Parameter               :: nin = 5, nout = 6
!     .. Local Scalars ..
      Real (Kind=nag_wp)               :: obj
      Integer                          :: i, ifail, iter, lda, ldh, liwork,    &
                                          lwork, n, nclin, sda
!     .. Local Arrays ..
      Real (Kind=nag_wp), Allocatable  :: a(:,:), ax(:), bl(:), bu(:),         &
                                          clamda(:), cvec(:), h(:,:), work(:), &
                                          x(:)
      Integer, Allocatable             :: istate(:), iwork(:)
!     .. Intrinsic Procedures ..
      Intrinsic                        :: max
!     .. Executable Statements ..
      Write (nout,*) 'E04NFF Example Program Results'
      Flush (nout)

!     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)

!     Solve the problem

      ifail = 0
      Call e04nff(n,nclin,a,lda,bl,bu,cvec,h,ldh,e04nfu,istate,x,iter,obj,ax,  &
        clamda,iwork,liwork,work,lwork,ifail)

    End Program e04nffe