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Updated: June 2017
 
 

zfftzm (3p)

Name

zfftzm - pute the one-dimensional Fast Fourier Transform (forward or inverse) of a set of data sequences stored in a two-dimensional double complex array.

Synopsis

SUBROUTINE ZFFTZM(IOPT, M, N, SCALE, X, LDX, Y, LDY, TRIGS, IFAC, WORK, LWORK, IERR)

INTEGER IOPT, M, N, LDX, LDY, IFAC(*), LWORK, IERR
DOUBLE COMPLEX X(LDX, *), Y(LDY, *)
DOUBLE PRECISION SCALE, TRIGS(*), WORK(*)

SUBROUTINE ZFFTZM_64(IOPT, M, N, SCALE, X, LDX, Y, LDY, TRIGS, IFAC, WORK, LWORK, IERR)

INTEGER*8 IOPT, M, N, LDX, LDY, IFAC(*), LWORK, IERR
DOUBLE PRECISION SCALE, TRIGS(*), WORK(*)
DOUBLE COMPLEX X(LDX, *), Y(LDY, *)




F95 INTERFACE
SUBROUTINE FFTM(IOPT, M, N, SCALE, X, LDX, Y, LDY, TRIGS,
IFAC, WORK, LWORK, IERR)

INTEGER, INTENT(IN) :: IOPT
INTEGER, INTENT(IN), OPTIONAL :: M, N, LDX, LDY, LWORK
REAL(8), INTENT(IN), OPTIONAL :: SCALE
COMPLEX(8), INTENT(IN), DIMENSION(:,:) :: X
COMPLEX(8), INTENT(OUT), DIMENSION(:,:) :: Y
REAL(8), INTENT(INOUT), DIMENSION(:) :: TRIGS
INTEGER, INTENT(INOUT), DIMENSION(:) :: IFAC
REAL(8), INTENT(OUT), DIMENSION(:) :: WORK
INTEGER, INTENT(OUT) :: IERR

SUBROUTINE FFTM_64(IOPT, M, N, SCALE, X, LDX, Y, LDY, TRIGS, IFAC, WORK, LWORK, IERR)

INTEGER(8), INTENT(IN) :: IOPT
INTEGER(8), INTENT(IN), OPTIONAL :: M, N, LDX, LDY, LWORK
REAL(8), INTENT(IN), OPTIONAL :: SCALE
COMPLEX(8), INTENT(IN), DIMENSION(:,:) :: X
COMPLEX(8), INTENT(OUT), DIMENSION(:,:) :: Y
REAL(8), INTENT(INOUT), DIMENSION(:) :: TRIGS
INTEGER(8), INTENT(INOUT), DIMENSION(:) :: IFAC
REAL(8), INTENT(OUT), DIMENSION(:) :: WORK
INTEGER(8), INTENT(OUT) :: IERR




C INTERFACE
#include <sunperf.h>

void zfftzm_ (int *iopt, int *m, int *n, double  *scale,  doublecomplex
*x,  int *ldx, doublecomplex *y, int *ldy, double *trigs, int
*ifac, double *work, int *lwork, int *ierr);

void zfftzm_64_ (long *iopt, long *m, long *n, double  *scale,  double-
complex  *x,  long  *ldx, doublecomplex *y, long *ldy, double
*trigs, long *ifac, double *work, long *lwork, long *ierr);

Description

Oracle Solaris Studio Performance Library                           zfftzm(3P)



NAME
       zfftzm  - initialize the trigonometric weight and factor tables or com-
       pute the one-dimensional Fast Fourier Transform (forward or inverse) of
       a  set  of  data  sequences  stored in a two-dimensional double complex
       array.

SYNOPSIS
       SUBROUTINE ZFFTZM(IOPT, M, N, SCALE, X, LDX, Y, LDY, TRIGS, IFAC, WORK, LWORK, IERR)

       INTEGER IOPT, M, N, LDX, LDY, IFAC(*), LWORK, IERR
       DOUBLE COMPLEX X(LDX, *), Y(LDY, *)
       DOUBLE PRECISION SCALE, TRIGS(*), WORK(*)

       SUBROUTINE ZFFTZM_64(IOPT, M, N, SCALE, X, LDX, Y, LDY, TRIGS, IFAC, WORK, LWORK, IERR)

       INTEGER*8 IOPT, M, N, LDX, LDY, IFAC(*), LWORK, IERR
       DOUBLE PRECISION SCALE, TRIGS(*), WORK(*)
       DOUBLE COMPLEX X(LDX, *), Y(LDY, *)




   F95 INTERFACE
       SUBROUTINE FFTM(IOPT, M, N, SCALE, X, LDX, Y, LDY, TRIGS,
                 IFAC, WORK, LWORK, IERR)

       INTEGER, INTENT(IN) :: IOPT
       INTEGER, INTENT(IN), OPTIONAL :: M, N, LDX, LDY, LWORK
       REAL(8), INTENT(IN), OPTIONAL :: SCALE
       COMPLEX(8), INTENT(IN), DIMENSION(:,:) :: X
       COMPLEX(8), INTENT(OUT), DIMENSION(:,:) :: Y
       REAL(8), INTENT(INOUT), DIMENSION(:) :: TRIGS
       INTEGER, INTENT(INOUT), DIMENSION(:) :: IFAC
       REAL(8), INTENT(OUT), DIMENSION(:) :: WORK
       INTEGER, INTENT(OUT) :: IERR

       SUBROUTINE FFTM_64(IOPT, M, N, SCALE, X, LDX, Y, LDY, TRIGS, IFAC, WORK, LWORK, IERR)

       INTEGER(8), INTENT(IN) :: IOPT
       INTEGER(8), INTENT(IN), OPTIONAL :: M, N, LDX, LDY, LWORK
       REAL(8), INTENT(IN), OPTIONAL :: SCALE
       COMPLEX(8), INTENT(IN), DIMENSION(:,:) :: X
       COMPLEX(8), INTENT(OUT), DIMENSION(:,:) :: Y
       REAL(8), INTENT(INOUT), DIMENSION(:) :: TRIGS
       INTEGER(8), INTENT(INOUT), DIMENSION(:) :: IFAC
       REAL(8), INTENT(OUT), DIMENSION(:) :: WORK
       INTEGER(8), INTENT(OUT) :: IERR




   C INTERFACE
       #include <sunperf.h>

       void zfftzm_ (int *iopt, int *m, int *n, double  *scale,  doublecomplex
                 *x,  int *ldx, doublecomplex *y, int *ldy, double *trigs, int
                 *ifac, double *work, int *lwork, int *ierr);

       void zfftzm_64_ (long *iopt, long *m, long *n, double  *scale,  double-
                 complex  *x,  long  *ldx, doublecomplex *y, long *ldy, double
                 *trigs, long *ifac, double *work, long *lwork, long *ierr);



PURPOSE
       zfftzm initializes the trigonometric weight and factor tables  or  com-
       putes  the  one-dimensional Fast Fourier Transform (forward or inverse)
       of a set of data sequences stored in a two-dimensional  double  complex
       array:

              M-1
       Y(k,l) = SUM  W*X(j,l)
              j=0

       where
       k ranges from 0 to M-1 and l ranges from 0 to N-1
       i = sqrt(-1)
       isign = 1 for inverse transform or -1 for forward transform
       W = exp(isign*i*j*k*2*pi/M)



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
                 IOPT = +1 computes inverse FFT

       M (input)
                 Integer specifying length of the input sequences. M  is  most
                 efficient  when  it  is  a  product of small primes.  M >= 0.
                 Unchanged on exit.

       N (input)
                 Integer specifying  number  of  input  sequences.   N  >=  0.
                 Unchanged on exit.

       SCALE (input)
                 Double  precision  scalar  by  which  transform  results  are
                 scaled.  Unchanged on exit.

       X (input) X is a double complex array of dimensions (LDX, N) that  con-
                 tains  the sequences to be transformed stored in its columns.

       LDX (input)
                 Leading dimension of X.  LDX >=M Unchanged on exit.

       Y (output)
                 Y is a double complex array of dimensions (LDY, N) that  con-
                 tains  the transform results of the input sequences.  X and Y
                 can be the same array starting at the same  memory  location,
                 in  which  case  the input sequences are overwritten by their
                 transform results.  Otherwise, it is assumed that there is no
                 overlap between X and Y in memory.

       LDY (input)
                 Leading dimension of Y.  If X and Y are the same array, LDY =
                 LDX Else LDY >=M Unchanged on exit.

       TRIGS (input/output)
                 Double precision  array  of  length  2*M  that  contains  the
                 trigonometric  weights.   The  weights  are computed when the
                 routine is called with IOPT = 0 and they are used  in  subse-
                 quent calls when IOPT = 1 or IOPT = -1.  Unchanged on exit.

       IFAC (input/output)
                 Integer  array  of  dimension  at least 128 that contains the
                 factors of M.  The factors are computed when the  routine  is
                 called  with  IOPT  = 0 and they are used in subsequent calls
                 when IOPT = 1 or IOPT = -1.  Unchanged on exit.

       WORK (workspace)
                 Double precision array of dimension at least 2*M*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, 1 or -1
                 -2 = M < 0
                 -3 = N < 0
                 -4 = (LDX < M)
                 -5 = (LDY < M) or (LDY not equal LDX when X and  Y  are  same
                 array)
                 -6 = (LWORK not equal 0) and (LWORK < 2*M*NCPUS)
                 -7 = memory allocation failed

SEE ALSO
       fft



                                  7 Nov 2015                        zfftzm(3P)