dezftb(3P) Sun Performance Library dezftb(3P)NAMEdezftb - computes a periodic sequence from its Fourier coefficients.
DEZFTB is a simplified but slower version of DFFTB.
SYNOPSIS
SUBROUTINE DEZFTB(N, R, AZERO, A, B, WSAVE)
INTEGER N
DOUBLE PRECISION AZERO
DOUBLE PRECISION R(*), A(*), B(*), WSAVE(*)
SUBROUTINE DEZFTB_64(N, R, AZERO, A, B, WSAVE)
INTEGER*8 N
DOUBLE PRECISION AZERO
DOUBLE PRECISION R(*), A(*), B(*), WSAVE(*)
F95 INTERFACE
SUBROUTINE DEZFTB(N, R, AZERO, A, B, WSAVE)
INTEGER :: N
REAL(8) :: AZERO
REAL(8), DIMENSION(:) :: R, A, B, WSAVE
SUBROUTINE DEZFTB_64(N, R, AZERO, A, B, WSAVE)
INTEGER(8) :: N
REAL(8) :: AZERO
REAL(8), DIMENSION(:) :: R, A, B, WSAVE
C INTERFACE
#include <sunperf.h>
void dezftb(int n, double *r, double azero, double *a, double *b, dou‐
ble *wsave);
void dezftb_64(long n, double *r, double azero, double *a, double *b,
double *wsave);
ARGUMENTS
N (input) Length of the sequence to be synthesized. The method is most
efficient when N is the product of small primes. N >= 0.
R (output)
On exit, the Fourier synthesis of the inputs.
AZERO (input)
On entry, the constant Fourier coefficient A0. Unchanged on
exit.
A (input) On entry, array that contains the remaining Fourier coeffi‐
cients. On exit, these arrays are unchanged.
B (input) On entry, array that contains the remaining Fourier coeffi‐
cients. On exit, these arrays are unchanged.
WSAVE (input)
On entry, an array with dimension of at least (3 * N + 15),
initialized by DEZFTI.
6 Mar 2009 dezftb(3P)
