rfft2i(3P) Sun Performance Library rfft2i(3P)NAMErfft2i - initialize the array WSAVE, which is used in both the forward
and backward transforms.
SYNOPSIS
SUBROUTINE RFFT2I(M, N, WORK)
INTEGER M, N
REAL WORK(*)
SUBROUTINE RFFT2I_64(M, N, WORK)
INTEGER*8 M, N
REAL WORK(*)
F95 INTERFACE
SUBROUTINE FFT2I(M, N, WORK)
INTEGER :: M, N
REAL, DIMENSION(:) :: WORK
SUBROUTINE FFT2I_64(M, N, WORK)
INTEGER(8) :: M, N
REAL, DIMENSION(:) :: WORK
C INTERFACE
#include <sunperf.h>
void rfft2i(int m, int n, float *work);
void rfft2i_64(long m, long n, float *work);
ARGUMENTS
M (input) Number of rows to be transformed. M >= 0.
N (input) Number of columns to be transformed. N >= 0.
WORK (input/output)
On entry, an array of dimension (M + 2*N + MAX(M, 2*N) + 30)
or greater. RFFT2I needs to be called only once to initial‐
ize array WORK before calling RFFT2F and/or RFFT2B if M, N
and WORK remain unchanged between these calls. Thus, subse‐
quent transforms or inverse transforms of same size can be
obtained faster than the first since they do not require ini‐
tialization of the workspace.
6 Mar 2009 rfft2i(3P)