cfftcm (3p)

Name

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

Synopsis

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

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

SUBROUTINE CFFTCM_64(IOPT, M, N, SCALE, X, LDX, Y, LDY, TRIGS, IFAC, WORK, LWORK, IERR)

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




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

INTEGER*4, INTENT(IN) :: IOPT
INTEGER*4, INTENT(IN), OPTIONAL :: M, N, LDX, LDY, LWORK
REAL, INTENT(IN), OPTIONAL :: SCALE
COMPLEX, 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 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, INTENT(IN), OPTIONAL :: SCALE
COMPLEX, 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  cfftcm_  (int  *iopt, int *n1, int *n2, float *scale, complex *x,
int *ldx, complex *y, int  *ldy,  float  *trigs,  int  *ifac,
float *work, int *lwork, int *ierr);

void  cfftcm_64_ (long *iopt, long *n1, long *n2, float *scale, complex
*x, long *ldx, complex *y,  long  *ldy,  float  *trigs,  long
*ifac, float *work, long *lwork, long *ierr);

Description

Oracle Solaris Studio Performance Library                           cfftcm(3P)



NAME
       cfftcm  - 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 complex array.

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

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

       SUBROUTINE CFFTCM_64(IOPT, M, N, SCALE, X, LDX, Y, LDY, TRIGS, IFAC, WORK, LWORK, IERR)

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




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

       INTEGER*4, INTENT(IN) :: IOPT
       INTEGER*4, INTENT(IN), OPTIONAL :: M, N, LDX, LDY, LWORK
       REAL, INTENT(IN), OPTIONAL :: SCALE
       COMPLEX, 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 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, INTENT(IN), OPTIONAL :: SCALE
       COMPLEX, 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  cfftcm_  (int  *iopt, int *n1, int *n2, float *scale, complex *x,
                 int *ldx, complex *y, int  *ldy,  float  *trigs,  int  *ifac,
                 float *work, int *lwork, int *ierr);

       void  cfftcm_64_ (long *iopt, long *n1, long *n2, float *scale, complex
                 *x, long *ldx, complex *y,  long  *ldy,  float  *trigs,  long
                 *ifac, float *work, long *lwork, long *ierr);



PURPOSE
       cfftcm  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 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)
                 Real scalar by which transform results are scaled.  Unchanged
                 on exit.

       X (input) X is a complex array of dimensions (LDX, N) that contains 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 complex array of dimensions (LDY, N) that contains 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)
                 Real  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 subsequent 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)
                 Real 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                        cfftcm(3P)