cosqf(3P) Sun Performance Library cosqf(3P)NAMEcosqf - compute the Fourier coefficients in a cosine series representa‐
tion with only odd wave numbers. The COSQ operations are unnormalized
inverses of themselves, so a call to COSQF followed by a call to COSQB
will multiply the input sequence by 4 * N.
SYNOPSIS
SUBROUTINE COSQF(N, X, WSAVE)
INTEGER N
REAL X(*), WSAVE(*)
SUBROUTINE COSQF_64(N, X, WSAVE)
INTEGER*8 N
REAL X(*), WSAVE(*)
F95 INTERFACE
SUBROUTINE COSQF(N, X, WSAVE)
INTEGER :: N
REAL, DIMENSION(:) :: X, WSAVE
SUBROUTINE COSQF_64(N, X, WSAVE)
INTEGER(8) :: N
REAL, DIMENSION(:) :: X, WSAVE
C INTERFACE
#include <sunperf.h>
void cosqf(int n, float *x, float *wsave);
void cosqf_64(long n, float *x, float *wsave);
ARGUMENTS
N (input) Length of the sequence to be transformed. These subroutines
are most efficient when N is a product of small primes. N >=
0.
X (input/output)
On entry, an array of length N containing the sequence to be
transformed. On exit, the quarter-wave cosine transform of
the input.
WSAVE (input)
On entry, an array with dimension of at least (3 * N + 15)
that has been initialized by COSQI.
6 Mar 2009 cosqf(3P)