ezfftf
ezfftf - computes the Fourier coefficients of a periodic sequence.
EZFFTF is a simplified but slower version of RFFTF.
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(*)
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
#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);
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* N (input)
-
Length of the sequence to be transformed. The method is most efficient when N is the product of
small primes. N >= 0.
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* R (output)
-
A real array of length N containing the sequence to be transformed. On exit, R is unchanged.
-
* AZERO (output)
-
On exit, the sum from i=1 to i=n of r(i)/n.
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* A (input/output)
-
On entry, arrays that contain the remaining Fourier coefficients. On exit,
these arrays are unchanged.
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* B (input/output)
-
On entry, arrays that contain the remaining Fourier coefficients. On exit,
these arrays are unchanged.
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* WSAVE (input)
-
On entry, an array with dimension of at least (3 * N + 15), initialized by EZFFTI.