sinq1i
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NAME
SINQ1I - initialization routine for SINQ1B and SINQ1F
SYNOPSIS
SUBROUTINE SINQ1I (N, WSAVE, LENSAV, IER)
INTEGER N, LENSAV, IER
REAL WSAVE(LENSAV)
DESCRIPTION
FFTPACK 5.0 subroutine SINQ1I initializes array WSAVE for use
in its companion routines SINQ1F and SINQ1B. The prime factor-
ization of N together with a tabulation of the trigonometric
functions are computed and stored in array WSAVE. Separate
WSAVE arrays are required for different values of N.
Input Arguments
N Integer length of the sequence to be transformed. The
transform is most efficient when N is a product of
small primes.
LENSAV Integer dimension of WSAVE array. LENSAV must be at least
2*N + INT(LOG (REAL(N))) +4.
Output Arguments
WSAVE Real work array with dimension LENSAV, containing the
prime factors of N and also containing certain trigonometric
values which will be used in routines SINQ1B or SINQ1F.
IER Integer error return
= 0 successful exit
= 2 input parameter LENSAV not big enough
= 20 input error returned by lower level routine