ezfftf(3P) Sun Performance Library ezfftf(3P)NAMEezfftf - computes the Fourier coefficients of a periodic sequence.
EZFFTF is a simplified but slower version of RFFTF.
SYNOPSIS
SUBROUTINE EZFFTF(N, R, AZERO, A, B, WSAVE)
INTEGER N
REAL AZERO
REAL R(*), A(*), B(*), WSAVE(*)
SUBROUTINE EZFFTF_64(N, R, AZERO, A, B, WSAVE)
INTEGER*8 N
REAL AZERO
REAL R(*), A(*), B(*), WSAVE(*)
F95 INTERFACE
SUBROUTINE EZFFTF(N, R, AZERO, A, B, WSAVE)
INTEGER :: N
REAL :: AZERO
REAL, DIMENSION(:) :: R, A, B, WSAVE
SUBROUTINE EZFFTF_64(N, R, AZERO, A, B, WSAVE)
INTEGER(8) :: N
REAL :: AZERO
REAL, DIMENSION(:) :: R, A, B, WSAVE
C INTERFACE
#include <sunperf.h>
void ezfftf(int n, float *r, float azero, float *a, float *b, float
*wsave);
void ezfftf_64(long n, float *r, float azero, float *a, float *b, float
*wsave);
ARGUMENTS
N (input) Length of the sequence to be transformed. The method is most
efficient when N is the product of small primes. N >= 0.
R (input) A real array of length N containing the sequence to be trans‐
formed. On exit, R is unchanged.
AZERO (output)
On exit, the sum from i=1 to i=n of r(i)/n.
A (output)
On exit, arrays that contain the remaining Fourier coeffi‐
cients.
B (output)
On exit, arrays that contain the remaining Fourier coeffi‐
cients.
WSAVE (input)
On entry, an array with dimension of at least (3 * N + 15),
initialized by EZFFTI.
6 Mar 2009 ezfftf(3P)