!   D01GDF Example Program Text
!   Mark 23 Release. NAG Copyright 2011.

    MODULE d01gdfe_mod

!      D01GDF Example Program Module:
!             Parameters and User-defined Routines

!      .. Use Statements ..
       USE nag_library, ONLY : nag_wp
!      .. Implicit None Statement ..
       IMPLICIT NONE
!      .. Parameters ..
       INTEGER, PARAMETER                  :: ndim = 4, nout = 6
    CONTAINS
       SUBROUTINE vecfun(ndim,x,fv,m)

!         .. Implicit None Statement ..
          IMPLICIT NONE
!         .. Scalar Arguments ..
          INTEGER, INTENT (IN)                :: m, ndim
!         .. Array Arguments ..
          REAL (KIND=nag_wp), INTENT (OUT)    :: fv(m)
          REAL (KIND=nag_wp), INTENT (IN)     :: x(m,ndim)
!         .. Local Scalars ..
          INTEGER                             :: i
!         .. Intrinsic Functions ..
          INTRINSIC                              cos, real, sum
!         .. Executable Statements ..
          DO i = 1, m
             fv(i) = cos(0.5E0_nag_wp+2.0E0_nag_wp*sum(x(i, &
                1:ndim))-real(ndim,kind=nag_wp))
          END DO

          RETURN

       END SUBROUTINE vecfun
       SUBROUTINE vecreg(ndim,x,j,c,d,m)

!         .. Implicit None Statement ..
          IMPLICIT NONE
!         .. Scalar Arguments ..
          INTEGER, INTENT (IN)                :: j, m, ndim
!         .. Array Arguments ..
          REAL (KIND=nag_wp), INTENT (OUT)    :: c(m), d(m)
          REAL (KIND=nag_wp), INTENT (IN)     :: x(m,ndim)
!         .. Executable Statements ..
          c(1:m) = 0.0E0_nag_wp
          d(1:m) = 1.0E0_nag_wp

          RETURN

       END SUBROUTINE vecreg
    END MODULE d01gdfe_mod
    PROGRAM d01gdfe

!      D01GDF Example Main Program

!      .. Use Statements ..
       USE nag_library, ONLY : d01gdf, nag_wp
       USE d01gdfe_mod, ONLY : ndim, nout, vecfun, vecreg
!      .. Implicit None Statement ..
       IMPLICIT NONE
!      .. Local Scalars ..
       REAL (KIND=nag_wp)                  :: err, res
       INTEGER                             :: ifail, itrans, npts, nrand
!      .. Local Arrays ..
       REAL (KIND=nag_wp)                  :: vk(ndim)
!      .. Executable Statements ..
       WRITE (nout,*) 'D01GDF Example Program Results'

       npts = 2
       itrans = 0
       nrand = 4

       ifail = 0
       CALL d01gdf(ndim,vecfun,vecreg,npts,vk,nrand,itrans,res,err,ifail)

       WRITE (nout,*)
       WRITE (nout,99999) 'Result = ', res, ', standard error = ', err

99999  FORMAT (1X,A,F13.5,A,E10.2)
    END PROGRAM d01gdfe