sfftc3 - pute the three-dimensional forward Fast Fourier Transform of a three- dimensional complex array.
SUBROUTINE SFFTC3(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 Y(LDY1, LDY2, *) REAL X(LDX1, LDX2, *), SCALE, TRIGS(*), WORK(*) SUBROUTINE SFFTC3_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 Y(LDY1, LDY2, *) REAL X(LDX1, LDX2, *), SCALE, TRIGS(*), WORK(*) 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, LDX2, LDY2 INTEGER*4, INTENT(IN), OPTIONAL :: M, N, K, LDX1, LDY1, LWORK REAL, INTENT(IN), OPTIONAL :: SCALE REAL, INTENT(IN), DIMENSION(:,:,:) :: X COMPLEX, 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, LDX2, LDY2 INTEGER(8), INTENT(IN), OPTIONAL :: M, N, K, LDX1, LDY1, LWORK REAL, INTENT(IN), OPTIONAL :: SCALE REAL, INTENT(IN), DIMENSION(:,:,:) :: X COMPLEX, 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 sfftc3_ (int *iopt, int *n1, int *n2, int *n3, float *scale, float *x, int *ldx1, int *ldx2, complex *y, int *ldy1, int *ldy2, float *trigs, int *ifac, float *work, int *lwork, int *ierr); void sfftc3_64_ (long *iopt, long *n1, long *n2, long *n3, float *scale, float *x, long *ldx1, long *ldx2, complex *y, long *ldy1, long *ldy2, float *trigs, long *ifac, float *work, long *lwork, long *ierr);
Oracle Solaris Studio Performance Library sfftc3(3P) NAME sfftc3 - initialize the trigonometric weight and factor tables or com- pute the three-dimensional forward Fast Fourier Transform of a three- dimensional complex array. SYNOPSIS SUBROUTINE SFFTC3(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 Y(LDY1, LDY2, *) REAL X(LDX1, LDX2, *), SCALE, TRIGS(*), WORK(*) SUBROUTINE SFFTC3_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 Y(LDY1, LDY2, *) REAL X(LDX1, LDX2, *), SCALE, TRIGS(*), WORK(*) 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, LDX2, LDY2 INTEGER*4, INTENT(IN), OPTIONAL :: M, N, K, LDX1, LDY1, LWORK REAL, INTENT(IN), OPTIONAL :: SCALE REAL, INTENT(IN), DIMENSION(:,:,:) :: X COMPLEX, 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, LDX2, LDY2 INTEGER(8), INTENT(IN), OPTIONAL :: M, N, K, LDX1, LDY1, LWORK REAL, INTENT(IN), OPTIONAL :: SCALE REAL, INTENT(IN), DIMENSION(:,:,:) :: X COMPLEX, 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 sfftc3_ (int *iopt, int *n1, int *n2, int *n3, float *scale, float *x, int *ldx1, int *ldx2, complex *y, int *ldy1, int *ldy2, float *trigs, int *ifac, float *work, int *lwork, int *ierr); void sfftc3_64_ (long *iopt, long *n1, long *n2, long *n3, float *scale, float *x, long *ldx1, long *ldx2, complex *y, long *ldy1, long *ldy2, float *trigs, long *ifac, float *work, long *lwork, long *ierr); PURPOSE sfftc3 initializes the trigonometric weight and factor tables or com- putes the three-dimensional forward 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 forward 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 forward 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 real array of dimensions (LDX1, LDX2, K) that contains input data to be transformed. X can be same array as Y. LDX1 (input) first dimension of X. If X is not same array as Y, LDX1 >= M Else, LDX1 = 2*LDY1 Unchanged on exit. LDX2 (input) second dimension of X. LDX2 >= N Unchanged on exit. Y (output) Y is a complex array of dimensions (LDY1, LDY2, K) that con- tains the transform results. X and Y can be the same array starting 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. LDY1 >= M/2+1 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) or (LDX not equal 2*LDY when X and Y are same array) -6 = (LDX2 < N) -7 = (LDY1 < M/2+1) -8 = (LDY2 < N) or (LDY2 not equal LDX2 when X and Y are same array) -9 = (LWORK not equal 0) and (LWORK < (MAX(N,2*N,2*K) + 16*K)*NCPUS) -10 = memory allocation failed SEE ALSO fft CAUTIONS This routine uses Y((M/2+1)+1:LDY1,:,:) as scratch space. Therefore, the original contents of this subarray will be lost upon returning from routine while subarray Y(1:M/2+1,1:N,1:K) contains the transform results. 7 Nov 2015 sfftc3(3P)