*
* Copyright (c) 1997-1999 Massachusetts Institute of Technology
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
*

c     Simple program to demonstrate calling the wrapper routines
c     to perform 1D transforms in Fortran.  This program should be
c       linked with -lfftw -lm.

      program test

      implicit none

      include "fftw3.f"

      integer N
      parameter(N=4)

      integer*8 plan
      double complex in, out
      dimension in(N),out(N)

      integer i

      write(*,*) 'Input array:'

      do i = 1,N,1
        in(i) = dcmplx(float(i),float(i+1))
        write(*,*) '    in(',i,') = ',in(i)
      enddo

      call dfftw_plan_dft_1d ( plan, N, in, out, FFTW_FORWARD, 
     ! FFTW_ESTIMATE )
      call dfftw_execute ( plan )

      write(*,*) 'Output array:'
      do i = 1,N,1
        write(*,*) '    out(',i,') = ',out(i)
      enddo

      call dfftw_destroy_plan ( plan )

      call dfftw_plan_dft_1d ( plan, N, out, in, FFTW_FORWARD, 
     ! FFTW_ESTIMATE )

      call dfftw_execute ( plan )

      write(*,*) 'Output array after inverse FFT:'
      do i = 1,N,1
        write(*,*) '    ',N,' * in(',i,') = ',in(i)
      enddo

      call dfftw_destroy_plan ( plan )

      end