Contents
dcosqi - initialize the array WSAVE, which is used in both
COSQF and COSQB.
SUBROUTINE DCOSQI(N, WSAVE)
INTEGER N
DOUBLE PRECISION WSAVE(*)
SUBROUTINE DCOSQI_64(N, WSAVE)
INTEGER*8 N
DOUBLE PRECISION WSAVE(*)
F95 INTERFACE
SUBROUTINE COSQI(N, WSAVE)
INTEGER :: N
REAL(8), DIMENSION(:) :: WSAVE
SUBROUTINE COSQI_64(N, WSAVE)
INTEGER(8) :: N
REAL(8), DIMENSION(:) :: WSAVE
C INTERFACE
#include <sunperf.h>
void dcosqi(int n, double *wsave);
void dcosqi_64(long n, double *wsave);
N (input) Length of the sequence to be transformed. The
method is most efficient when N is a product of
small primes.
WSAVE (input)
On entry, an array of dimension (3 * N + 15) or
greater. DCOSQI needs to be called only once to
initialize WSAVE before calling DCOSQF and/or
DCOSQB if N and WSAVE remain unchanged between
these calls. Thus, subsequent transforms or
inverse transforms of same size can be obtained
faster than the first since they do not require
initialization of the workspace.