cffts3 - pute the three-dimensional inverse Fast Fourier Transform of a three- dimensional complex array.
SUBROUTINE CFFTS3(IOPT, M, N, K, SCALE, X, LDX1, LDX2, Y, LDY1, LDY2, TRIGS, IFAC, WORK, LWORK, IERR) INTEGER IOPT, M, N, K, LDX1, LDX2, LDY1, LDY2, IFAC(*), LWORK, IERR COMPLEX X(LDX1, LDX2, *) REAL SCALE, TRIGS(*), WORK(*), Y(LDY1, LDY2, *) SUBROUTINE CFFTS3_64(IOPT, M, N, K, SCALE, X, LDX1, LDX2, Y, LDY1, LDY2, TRIGS, IFAC, WORK, LWORK, IERR) INTEGER*8 IOPT, M, N, K, LDX1, LDX2, LDY1, LDY2, IFAC(*), LWORK, IERR COMPLEX X(LDX1, LDX2, *) REAL SCALE, TRIGS(*), WORK(*), Y(LDY1, LDY2, *) F95 INTERFACE SUBROUTINE FFT3(IOPT, M, N, K, SCALE, X, LDX1, LDX2, Y, LDY1, LDY2, TRIGS, IFAC, WORK, LWORK, IERR) INTEGER*4, INTENT(IN) :: IOPT, M, LDX2, LDY2 INTEGER*4, INTENT(IN), OPTIONAL :: N, K, LDX1, LDY1, LWORK REAL, INTENT(IN), OPTIONAL :: SCALE COMPLEX, INTENT(IN), DIMENSION(:,:,:) :: X REAL, INTENT(OUT), DIMENSION(:,:,:) :: Y REAL, INTENT(INOUT), DIMENSION(:) :: TRIGS INTEGER*4, INTENT(INOUT), DIMENSION(:) :: IFAC REAL, INTENT(OUT), DIMENSION(:) :: WORK INTEGER*4, INTENT(OUT) :: IERR SUBROUTINE FFT3_64(IOPT, M, N, K, SCALE, X, LDX1, LDX2, Y, LDY1, LDY2, TRIGS, IFAC, WORK, LWORK, IERR) INTEGER(8), INTENT(IN) :: IOPT, M, LDX2, LDY2 INTEGER(8), INTENT(IN), OPTIONAL :: N, K, LDX1, LDY1, LWORK REAL, INTENT(IN), OPTIONAL :: SCALE COMPLEX, INTENT(IN), DIMENSION(:,:,:) :: X REAL, INTENT(OUT), DIMENSION(:,:,:) :: Y REAL, INTENT(INOUT), DIMENSION(:) :: TRIGS INTEGER(8), INTENT(INOUT), DIMENSION(:) :: IFAC REAL, INTENT(OUT), DIMENSION(:) :: WORK INTEGER(8), INTENT(OUT) :: IERR C INTERFACE #include <sunperf.h> void cffts3_ (int *iopt, int *n1, int *n2, int *n3, float *scale, com- plex *x, int *ldx1, int *ldx2, float *y, int *ldy1, int *ldy2, float *trigs, int *ifac, float *work, int *lwork, int *ierr); void cffts3_64_ (long *iopt, long *n1, long *n2, long *n3, float *scale, complex *x, long *ldx1, long *ldx2, float *y, long *ldy1, long *ldy2, float *trigs, long *ifac, float *work, long *lwork, long *ierr);
Oracle Solaris Studio Performance Library cffts3(3P) NAME cffts3 - initialize the trigonometric weight and factor tables or com- pute the three-dimensional inverse Fast Fourier Transform of a three- dimensional complex array. SYNOPSIS SUBROUTINE CFFTS3(IOPT, M, N, K, SCALE, X, LDX1, LDX2, Y, LDY1, LDY2, TRIGS, IFAC, WORK, LWORK, IERR) INTEGER IOPT, M, N, K, LDX1, LDX2, LDY1, LDY2, IFAC(*), LWORK, IERR COMPLEX X(LDX1, LDX2, *) REAL SCALE, TRIGS(*), WORK(*), Y(LDY1, LDY2, *) SUBROUTINE CFFTS3_64(IOPT, M, N, K, SCALE, X, LDX1, LDX2, Y, LDY1, LDY2, TRIGS, IFAC, WORK, LWORK, IERR) INTEGER*8 IOPT, M, N, K, LDX1, LDX2, LDY1, LDY2, IFAC(*), LWORK, IERR COMPLEX X(LDX1, LDX2, *) REAL SCALE, TRIGS(*), WORK(*), Y(LDY1, LDY2, *) F95 INTERFACE SUBROUTINE FFT3(IOPT, M, N, K, SCALE, X, LDX1, LDX2, Y, LDY1, LDY2, TRIGS, IFAC, WORK, LWORK, IERR) INTEGER*4, INTENT(IN) :: IOPT, M, LDX2, LDY2 INTEGER*4, INTENT(IN), OPTIONAL :: N, K, LDX1, LDY1, LWORK REAL, INTENT(IN), OPTIONAL :: SCALE COMPLEX, INTENT(IN), DIMENSION(:,:,:) :: X REAL, INTENT(OUT), DIMENSION(:,:,:) :: Y REAL, INTENT(INOUT), DIMENSION(:) :: TRIGS INTEGER*4, INTENT(INOUT), DIMENSION(:) :: IFAC REAL, INTENT(OUT), DIMENSION(:) :: WORK INTEGER*4, INTENT(OUT) :: IERR SUBROUTINE FFT3_64(IOPT, M, N, K, SCALE, X, LDX1, LDX2, Y, LDY1, LDY2, TRIGS, IFAC, WORK, LWORK, IERR) INTEGER(8), INTENT(IN) :: IOPT, M, LDX2, LDY2 INTEGER(8), INTENT(IN), OPTIONAL :: N, K, LDX1, LDY1, LWORK REAL, INTENT(IN), OPTIONAL :: SCALE COMPLEX, INTENT(IN), DIMENSION(:,:,:) :: X REAL, INTENT(OUT), DIMENSION(:,:,:) :: Y REAL, INTENT(INOUT), DIMENSION(:) :: TRIGS INTEGER(8), INTENT(INOUT), DIMENSION(:) :: IFAC REAL, INTENT(OUT), DIMENSION(:) :: WORK INTEGER(8), INTENT(OUT) :: IERR C INTERFACE #include <sunperf.h> void cffts3_ (int *iopt, int *n1, int *n2, int *n3, float *scale, com- plex *x, int *ldx1, int *ldx2, float *y, int *ldy1, int *ldy2, float *trigs, int *ifac, float *work, int *lwork, int *ierr); void cffts3_64_ (long *iopt, long *n1, long *n2, long *n3, float *scale, complex *x, long *ldx1, long *ldx2, float *y, long *ldy1, long *ldy2, float *trigs, long *ifac, float *work, long *lwork, long *ierr); PURPOSE cffts3 initializes the trigonometric weight and factor tables or com- putes the three-dimensional inverse Fast Fourier Transform of a three-dimensional complex array. K-1 N-1 M-1 Y(k1,k2,k3) = scale * SUM SUM SUM W3*W2*W1*X(j1,j2,j3) j3=0 j2=0 j1=0 where k1 ranges from 0 to M-1; k2 ranges from 0 to N-1 and k3 ranges from 0 to K-1 i = sqrt(-1) isign = 1 for inverse transform W1 = exp(isign*i*j1*k1*2*pi/M) W2 = exp(isign*i*j2*k2*2*pi/N) W3 = exp(isign*i*j3*k3*2*pi/K) ARGUMENTS IOPT (input) Integer specifying the operation to be performed: IOPT = 0 computes the trigonometric weight table and factor table IOPT = +1 computes inverse FFT M (input) Integer specifying length of the transform in the first dimension. M is most efficient when it is a product of small primes. M >= 0. Unchanged on exit. N (input) Integer specifying length of the transform in the second dimension. N is most efficient when it is a product of small primes. N >= 0. Unchanged on exit. K (input) Integer specifying length of the transform in the third dimension. K is most efficient when it is a product of small primes. K >= 0. Unchanged on exit. SCALE (input) Real scalar by which transform results are scaled. Unchanged on exit. X (input) X is a complex array of dimensions (LDX1, LDX2, K) that con- tains input data to be transformed. LDX1 (input) first dimension of X. LDX1 >= M/2+1 Unchanged on exit. LDX2 (input) second dimension of X. LDX2 >= N Unchanged on exit. Y (output) Y is a real array of dimensions (LDY1, LDY2, K) that contains the transform results. X and Y can be the same array start- ing at the same memory location, in which case the input data are overwritten by their transform results. Otherwise, it is assumed that there is no overlap between X and Y in memory. LDY1 (input) first dimension of Y. If X and Y are the same array, LDY1 = 2*LDX1 Else LDY1 >= 2*LDX1 and LDY1 is even Unchanged on exit. LDY2 (input) second dimension of Y. If X and Y are the same array, LDY2 = LDX2 Else LDY2 >= N Unchanged on exit. TRIGS (input/output) Real array of length 2*(M+N+K) that contains the trigonomet- ric weights. The weights are computed when the routine is called with IOPT = 0 and they are used in subsequent calls when IOPT = 1. Unchanged on exit. IFAC (input/output) Integer array of dimension at least 3*128 that contains the factors of M, N and K. The factors are computed when the routine is called with IOPT = 0 and they are used in subse- quent calls when IOPT = 1. Unchanged on exit. WORK (workspace) Real array of dimension at least (MAX(N,2*N,2*K) + 16*K) * NCPUS where NCPUS is the number of threads used to execute the routine. The user can also choose to have the routine allocate its own workspace (see LWORK). LWORK (input) Integer specifying workspace size. If LWORK = 0, the routine will allocate its own workspace. IERR (output) On exit, integer IERR has one of the following values: 0 = normal return -1 = IOPT is not 0 or 1 -2 = M < 0 -3 = N < 0 -4 = K < 0 -5 = (LDX1 < M/2+1) -6 = (LDX2 < N) -7 = LDY1 not equal 2*LDX1 when X and Y are same array -8 = (LDY1 < 2*LDX1) or (LDY1 is odd) when X and Y are not same array -9 = (LDY2 < N) or (LDY2 not equal LDX2) when X and Y are same array -10 = (LWORK not equal 0) and ((LWORK < MAX(N,2*N,2*K) + 16*K)*NCPUS) -11 = memory allocation failed SEE ALSO fft CAUTIONS This routine uses Y(M+1:LDY1,:,:) as scratch space. Therefore, the original contents of this subarray will be lost upon returning from routine while subarray Y(1:M,1:N,1:K) contains the transform results. 7 Nov 2015 cffts3(3P)