NAG Library Manual, Mark 29.3
```    Program g13mgfe
!     G13MGF Example Program Text

!     Mark 29.3 Release. NAG Copyright 2023.

!     .. Use Statements ..
Use nag_library, Only: g13mgf, nag_wp
!     .. Implicit None Statement ..
Implicit None
!     .. Parameters ..
Integer, Parameter               :: nin = 5, nout = 6
!     .. Local Scalars ..
Real (Kind=nag_wp)               :: p, tau
Integer                          :: ftype, i, ierr, ifail, lrcomm,       &
lsinit, m1, m2, nb, pn
!     .. Local Arrays ..
Real (Kind=nag_wp), Allocatable  :: ma(:), rcomm(:), sinit(:), t(:),     &
wma(:)
Integer                          :: inter(2)
!     .. Intrinsic Procedures ..
Intrinsic                        :: repeat
!     .. Executable Statements ..
Write (nout,*) 'G13MGF Example Program Results'
Write (nout,*)

!     Skip heading in data file

!     Read in the number of iterations required

!     Read in the transformation function, its parameter, the interpolation
!     method to use and the decay parameter tau
Read (nin,*) ftype, p, inter(1:2), tau

!     Read in the initial values
If (ftype==3 .Or. ftype==5) Then
lsinit = 2*m2 + 3
Else
lsinit = m2 + 2
End If
Allocate (sinit(lsinit))

!     Print some titles
Write (nout,99997) 'Time', 'MA'
Write (nout,99998) repeat('-',32)

lrcomm = 20 + 2*m2
Allocate (rcomm(lrcomm))

!     Loop over each block of data
pn = 0
Do
!       Read in the number of observations in this block
If (ierr/=0) Then
Exit
End If

!       Allocate MA, T and WMA to the required size
Allocate (ma(nb),t(nb),wma(nb))

!       Read in the data for this block
Do i = 1, nb
End Do

!       Update the moving average operator for this block of data
!       G13MGF overwrites the input data
ifail = 0
Call g13mgf(nb,ma,t,tau,m1,m2,sinit,inter,ftype,p,pn,wma,rcomm,lrcomm, &
ifail)

!       Display the results for this block of data
Write (nout,99999)(pn-nb+i,t(i),ma(i),i=1,nb)
Write (nout,*)

Deallocate (t,ma,wma)
End Do

99999 Format (1X,I3,4X,F10.1,4X,F10.3)
99998 Format (1X,A)
99997 Format (14X,A,10X,A)
End Program g13mgfe
```