```    Program g02apfe

!     G02APF Example Program Text

!     Mark 26 Release. NAG Copyright 2016.

!     .. Use Statements ..
Use nag_library, Only: dsyev, g02apf, nag_wp, x04caf
!     .. Implicit None Statement ..
Implicit None
!     .. Parameters ..
Integer, Parameter               :: nin = 5, nout = 6
!     .. Local Scalars ..
Real (Kind=nag_wp)               :: alpha, eigmin, eigtol, errtol, norm, &
theta
Integer                          :: i, ifail, iter, ldg, ldh, ldx,       &
lwork, n
!     .. Local Arrays ..
Real (Kind=nag_wp), Allocatable  :: eig(:), g(:,:), h(:,:), work(:),     &
x(:,:)
!     .. Executable Statements ..
Write (nout,*) 'G02APF Example Program Results'
Write (nout,*)
Flush (nout)

!     Skip heading in data file

!     Read in the problem size and theta

ldg = n
ldh = n
ldx = n
lwork = 66*n
Allocate (g(ldg,n),h(ldh,n),x(ldx,n),eig(n),work(lwork))

!     Read in the matrix G

!     Read in the matrix H

!     Use the defaults for EIGTOL and ERRTOL
eigtol = -1.E0_nag_wp
errtol = -1.E0_nag_wp

!     Calculate nearest correlation matrix using target matrix
ifail = 0

Call g02apf(g,ldg,n,theta,h,ldh,errtol,eigtol,x,ldx,alpha,iter,eigmin,   &
norm,ifail)

ifail = 0
!     Display the symmetrised input matrix
Call x04caf('General',' ',n,n,g,ldg,'Symmetrised Input Matrix G',ifail)
Write (nout,*)

!     Display results
ifail = 0
Call x04caf('General',' ',n,n,x,ldx,'Nearest Correlation Matrix X',      &
ifail)
Write (nout,*)
Write (nout,99999) 'Number of iterations taken:', iter
Write (nout,*)
Write (nout,99998) 'ALPHA:                        ', alpha
Write (nout,*)
Write (nout,99998) 'Norm value:                   ', norm
Write (nout,*)
Write (nout,99998) 'THETA:                        ', theta
Write (nout,*)
Write (nout,99998) 'Smallest eigenvalue of target:', eigmin

ifail = 0
!     Compute the eigenvalues of X
Call dsyev('N','U',n,x,ldx,eig,work,lwork,ifail)
Write (nout,*)
Flush (nout)
Call x04caf('General',' ',1,n,eig,1,'Eigenvalues of X',ifail)

99999 Format (1X,A,I9)
99998 Format (1X,A,F11.4)

End Program g02apfe
```