Contents
vzfftf - compute the Fourier coefficients of a periodic
sequence. The VZFFT operations are normalized, so a call of
VZFFTF followed by a call of VZFFTB will return the original
sequence.
SUBROUTINE VZFFTF(M, N, X, XT, MDIMX, ROWCOL, WSAVE)
CHARACTER * 1 ROWCOL
DOUBLE COMPLEX X(MDIMX,*), XT(MDIMX,*), WSAVE(*)
INTEGER M, N, MDIMX
SUBROUTINE VZFFTF_64(M, N, X, XT, MDIMX, ROWCOL, WSAVE)
CHARACTER * 1 ROWCOL
DOUBLE COMPLEX X(MDIMX,*), XT(MDIMX,*), WSAVE(*)
INTEGER*8 M, N, MDIMX
F95 INTERFACE
SUBROUTINE FFTF([M], [N], X, XT, [MDIMX], ROWCOL, WSAVE)
CHARACTER(LEN=1) :: ROWCOL
COMPLEX(8), DIMENSION(:) :: WSAVE
COMPLEX(8), DIMENSION(:,:) :: X, XT
INTEGER :: M, N, MDIMX
SUBROUTINE FFTF_64([M], [N], X, XT, [MDIMX], ROWCOL, WSAVE)
CHARACTER(LEN=1) :: ROWCOL
COMPLEX(8), DIMENSION(:) :: WSAVE
COMPLEX(8), DIMENSION(:,:) :: X, XT
INTEGER(8) :: M, N, MDIMX
C INTERFACE
#include <sunperf.h>
void vzfftf(int m, int n, doublecomplex *x, doublecomplex
*xt, int mdimx, char rowcol, doublecomplex
*wsave);
void vzfftf_64(long m, long n, doublecomplex *x, doublecom-
plex *xt, long mdimx, char rowcol, doublecomplex
*wsave);
M (input) The number of sequences to be transformed. M >=
0.
N (input) Length of the sequence to be transformed. These
subroutines are most efficient when N is a product
of small primes. N >= 0.
X (input) On entry, an array X(M,N) whose rows contain the
sequences to be transformed.
XT (input)
A work array.
MDIMX (input)
Leading dimension of the arrays X and XT as speci-
fied in a dimension or type statement. MDIMX >=
M.
ROWCOL (input)
Indicates whether to transform rows ('R' or 'r')
or columns ('C' or 'c').
WSAVE (input/output)
On entry, an array of dimension (K+15) or greater,
where K = M if ROWCOL = ('R' or 'r'). Otherwise,
K = N. WSAVE is initialized by VZFFTI.