! ! $Id: mod_fft_fftw.F90 1601 2011-12-07 07:05:43Z crisi $ ! MODULE mod_fft_fftw #ifdef FFT_FFTW REAL, SAVE :: scale_factor INTEGER, SAVE :: vsize INTEGER, PARAMETER :: inc=1 INTEGER*8, ALLOCATABLE, DIMENSION(:), SAVE :: plan_forward INTEGER*8, ALLOCATABLE, DIMENSION(:), SAVE :: plan_backward CONTAINS SUBROUTINE Init_fft(iim,nvectmax) IMPLICIT NONE #include INTEGER :: iim INTEGER :: nvectmax INTEGER :: itmp INTEGER :: rank INTEGER :: howmany INTEGER :: istride, idist INTEGER :: ostride, odist INTEGER, DIMENSION(1) :: n_array, inembed, onembed REAL, DIMENSION(iim+1,nvectmax) :: dbidon COMPLEX, DIMENSION(iim/2+1,nvectmax) :: cbidon vsize = iim scale_factor = 1./SQRT(1.*vsize) dbidon = 0 cbidon = 0 ALLOCATE(plan_forward(nvectmax)) ALLOCATE(plan_backward(nvectmax)) WRITE(*,*)"!---------------------!" WRITE(*,*)"! !" WRITE(*,*)"! INITIALISATION FFTW !" WRITE(*,*)"! !" WRITE(*,*)"!---------------------!" ! On initialise tous les plans DO itmp = 1, nvectmax rank = 1 n_array(1) = iim howmany = itmp inembed(1) = iim + 1 ; onembed(1) = iim/2 + 1 istride = 1 ; ostride = 1 idist = iim + 1 ; odist = iim/2 + 1 CALL dfftw_plan_many_dft_r2c(plan_forward(itmp), rank, n_array, howmany, & & dbidon, inembed, istride, idist, & & cbidon, onembed, ostride, odist, & & FFTW_ESTIMATE) rank = 1 n_array(1) = iim howmany = itmp inembed(1) = iim/2 + 1 ; onembed(1) = iim + 1 istride = 1 ; ostride = 1 idist = iim/2 + 1 ; odist = iim + 1 CALL dfftw_plan_many_dft_c2r(plan_backward(itmp), rank, n_array, howmany, & & cbidon, inembed, istride, idist, & & dbidon, onembed, ostride, odist, & & FFTW_ESTIMATE) ENDDO WRITE(*,*)"!-------------------------!" WRITE(*,*)"! !" WRITE(*,*)"! FIN INITIALISATION FFTW !" WRITE(*,*)"! !" WRITE(*,*)"!-------------------------!" END SUBROUTINE Init_fft SUBROUTINE fft_forward(vect,TF_vect,nb_vect) IMPLICIT NONE #include INTEGER,INTENT(IN) :: nb_vect REAL,INTENT(IN) :: vect(vsize+inc,nb_vect) COMPLEX,INTENT(OUT) :: TF_vect(vsize/2+1,nb_vect) CALL dfftw_execute_dft_r2c(plan_forward(nb_vect),vect,TF_vect) TF_vect = scale_factor * TF_vect END SUBROUTINE fft_forward SUBROUTINE fft_backward(TF_vect,vect,nb_vect) IMPLICIT NONE #include INTEGER,INTENT(IN) :: nb_vect REAL,INTENT(OUT) :: vect(vsize+inc,nb_vect) COMPLEX,INTENT(IN ) :: TF_vect(vsize/2+1,nb_vect) CALL dfftw_execute_dft_c2r(plan_backward(nb_vect),TF_vect,vect) vect = scale_factor * vect END SUBROUTINE fft_backward #endif END MODULE mod_fft_fftw