dcosqi
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(*)
SUBROUTINE COSQI( N, WSAVE)
INTEGER :: N
REAL(8), DIMENSION(:) :: WSAVE
SUBROUTINE COSQI_64( N, WSAVE)
INTEGER(8) :: N
REAL(8), DIMENSION(:) :: WSAVE
#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.