XLPack 6.0
Excel VBA Numerical Library Reference Manual
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◆ Sint1i()

Sub Sint1i ( N As  Long,
Wsave() As  Double,
Info As  Long 
)

Initialization of work data for Sint1f and Sint1b

Purpose
This routine initializes array Wsave() for use in its companion routines Sint1f and Sint1b. The prime factorization of N together with a tabulation of the trigonometric functions are computed and stored in array Wsave().

Note - The initialization of Wsave() is not necessary for the succeeding call of Sint1f or Sint1b for the same N value. If the value of N has been changed, Wsave() should be re-initialized by this routine.
Parameters
[in]NThe length of the sequence to be transformed. (N >= 1) (The transform is most efficient when N+1 is a product of small primes)
[out]Wsave()Array Wsave(LWsave - 1) (LWsave >= N/2 + N + ln(N)/ln(2) + 4)
Work data, containing the prime factors of N and also containing certain trigonometric values which will be used in routines Sint1f and Sint1b.
[out]Info= 0: Successful exit.
= -1: The argument N had an illegal value. (N < 1)
= -2: The argument Wsave() is invalid.
Reference
FFTPACK
Example Program
See example of Sint1f.