subroutine ifft( A, N ) integer*4 N complex*16 A(*) ! Routine to compute inverse Fourier transform using FFT algorithm ! Inputs ! A Complex transform data vector ! N Number of data points ! Outputs ! A Complex time series integer*4 i !* Take complex conjugate of input transform do i=1,N A(i) = conjg(A(i)) ! Complex conjugate enddo !* Evaluate fast fourier transform call fft( A, N ) !* Take complex conjugate and normalize by N do i=1,N A(i) = conjg(A(i))/N ! Normalize and complex conjugate enddo return end