cfft3b(3P) Sun Performance Library cfft3b(3P)NAMEcfft3b - compute a periodic sequence from its Fourier coefficients.
The FFT operations are unnormalized, so a call of CFFT3F followed by a
call of CFFT3B will multiply the input sequence by M*N*K.
SYNOPSIS
SUBROUTINE CFFT3B(M, N, K, A, LDA, LD2A, WORK, LWORK)
COMPLEX A(LDA,LD2A,*)
INTEGER M, N, K, LDA, LD2A, LWORK
REAL WORK(*)
SUBROUTINE CFFT3B_64(M, N, K, A, LDA, LD2A, WORK, LWORK)
COMPLEX A(LDA,LD2A,*)
INTEGER*8 M, N, K, LDA, LD2A, LWORK
REAL WORK(*)
F95 INTERFACE
SUBROUTINE FFT3B([M], [N], [K], A, [LDA], LD2A, WORK, LWORK)
COMPLEX, DIMENSION(:,:,:) :: A
INTEGER :: M, N, K, LDA, LD2A, LWORK
REAL, DIMENSION(:) :: WORK
SUBROUTINE FFT3B_64([M], [N], [K], A, [LDA], LD2A, WORK, LWORK)
COMPLEX, DIMENSION(:,:,:) :: A
INTEGER(8) :: M, N, K, LDA, LD2A, LWORK
REAL, DIMENSION(:) :: WORK
C INTERFACE
#include <sunperf.h>
void cfft3b(int m, int n, int k, complex *a, int lda, int ld2a, float
*work, int lwork);
void cfft3b_64(long m, long n, long k, complex *a, long lda, long ld2a,
float *work, long lwork);
ARGUMENTS
M (input) Number of rows to be transformed. These subroutines are most
efficient when M is a product of small primes. M >= 0.
N (input) Number of columns to be transformed. These subroutines are
most efficient when N is a product of small primes. N >= 0.
K (input) Number of planes to be transformed. These subroutines are
most efficient when K is a product of small primes. K >= 0.
A (input/output)
On entry, a three-dimensional array A(LDA,LD2A,K) that con‐
tains the sequences to be transformed.
LDA (input)
Leading dimension of the array containing the data to be
transformed. LDA >= M.
LD2A (input)
Second dimension of the array containing the data to be
transformed. LD2A >= N.
WORK (input)
On input, workspace WORK must have been initialized by
CFFT3I.
LWORK (input)
The dimension of the array WORK. LWORK >= (4*(M + N + K) +
45).
6 Mar 2009 cfft3b(3P)
