rffti(3P) Sun Performance Library rffti(3P)NAMErffti - initialize the array WSAVE, which is used in both RFFTF and
RFFTB.
SYNOPSIS
SUBROUTINE RFFTI(N, WSAVE)
INTEGER N
REAL WSAVE(*)
SUBROUTINE RFFTI_64(N, WSAVE)
INTEGER*8 N
REAL WSAVE(*)
F95 INTERFACE
SUBROUTINE FFTI(N, WSAVE)
INTEGER :: N
REAL, DIMENSION(:) :: WSAVE
SUBROUTINE FFTI_64(N, WSAVE)
INTEGER(8) :: N
REAL, DIMENSION(:) :: WSAVE
C INTERFACE
#include <sunperf.h>
void rffti(int n, float *wsave);
void rffti_64(long n, float *wsave);
ARGUMENTS
N (input) Length of the sequence to be transformed. N >= 0.
WSAVE (input/output)
On entry, an array of dimension (2 * N + 15) or greater.
RFFTI needs to be called only once to initialize array WORK
before calling RFFTF and/or RFFTB 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.
6 Mar 2009 rffti(3P)