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*
* Copyright (c) 1997-1999, 2003 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 (assuming double-precision FFTW). Note
c also that the plan should be integer*8 on a 64-bit machine.
program test
implicit none
#include "fftw_f77.i"
integer N
parameter(N=4)
double complex in, out
dimension in(N),out(N)
integer i
integer plan
write(*,*) 'Input array:'
do i = 1,N,1
in(i) = dcmplx(float(i),float(i+1))
write(*,*) ' in(',i,') = ',in(i)
enddo
call fftw_f77_create_plan(plan,N,FFTW_FORWARD,FFTW_ESTIMATE)
call fftw_f77(plan,1,in,1,0,out,1,0)
write(*,*) 'Output array:'
do i = 1,N,1
write(*,*) ' out(',i,') = ',out(i)
enddo
call fftw_f77_destroy_plan(plan)
call fftw_f77_create_plan(plan,N,FFTW_BACKWARD,FFTW_ESTIMATE)
call fftw_f77(plan,1,out,1,0,in,1,0)
write(*,*) 'Output array after inverse FFT:'
do i = 1,N,1
write(*,*) ' ',N,' * in(',i,') = ',in(i)
enddo
call fftw_f77_destroy_plan(plan)
end
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