ezfftb

NAME

ezfftb - computes a periodic sequence from its Fourier coefficients. EZFFTB is a simplified but slower version of RFFTB.

SYNOPSIS

  SUBROUTINE EZFFTB( N, R, AZERO, A, B, WSAVE)
  INTEGER N
  REAL AZERO
  REAL R(*), A(*), B(*), WSAVE(*)
 
  SUBROUTINE EZFFTB_64( N, R, AZERO, A, B, WSAVE)
  INTEGER*8 N
  REAL AZERO
  REAL R(*), A(*), B(*), WSAVE(*)

F95 INTERFACE

  SUBROUTINE EZFFTB( [N], R, AZERO, A, B, WSAVE)
  INTEGER :: N
  REAL :: AZERO
  REAL, DIMENSION(:) :: R, A, B, WSAVE
 
  SUBROUTINE EZFFTB_64( [N], R, AZERO, A, B, WSAVE)
  INTEGER(8) :: N
  REAL :: AZERO
  REAL, DIMENSION(:) :: R, A, B, WSAVE

C INTERFACE

#include <sunperf.h>

void ezfftb(int n, float *r, float azero, float *a, float *b, float *wsave);

void ezfftb_64(long n, float *r, float azero, float *a, float *b, float *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/output): On entry, arrays that contain the remaining Fourier coefficients. On exit, these arrays are unchanged.
* B (input/output): On entry, arrays that contain the remaining Fourier coefficients. On exit, these arrays are unchanged.
* WSAVE (input): On entry, an array with dimension of at least (3 * N + 15), initialized by EZFFTI.