vdcosqb(3P) Sun Performance Library vdcosqb(3P)NAMEvdcosqb - synthesize a Fourier sequence from its representation in
terms of a cosine series with odd wave numbers. The VCOSQ operations
are normalized, so a call of VCOSQF followed by a call of VCOSQB will
return the original sequence.
SYNOPSIS
SUBROUTINE VDCOSQB(M, N, X, XT, MDIMX, WSAVE)
INTEGER M, N, MDIMX
DOUBLE PRECISION X(MDIMX,*), XT(MDIMX,*), WSAVE(*)
SUBROUTINE VDCOSQB_64(M, N, X, XT, MDIMX, WSAVE)
INTEGER*8 M, N, MDIMX
DOUBLE PRECISION X(MDIMX,*), XT(MDIMX,*), WSAVE(*)
F95 INTERFACE
SUBROUTINE COSQB([M], [N], X, XT, [MDIMX], WSAVE)
INTEGER :: M, N, MDIMX
REAL(8), DIMENSION(:) :: WSAVE
REAL(8), DIMENSION(:,:) :: X, XT
SUBROUTINE COSQB_64([M], [N], X, XT, [MDIMX], WSAVE)
INTEGER(8) :: M, N, MDIMX
REAL(8), DIMENSION(:) :: WSAVE
REAL(8), DIMENSION(:,:) :: X, XT
C INTERFACE
#include <sunperf.h>
void vdcosqb(int m, int n, double *x, double *xt, int mdimx, double
*wsave);
void vdcosqb_64(long m, long n, double *x, double *xt, long mdimx, dou‐
ble *wsave);
ARGUMENTS
M (input) The number of sequences to be transformed. M >= 0.
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, the rows contain the sequences to be transformed.
On exit, the quarter-wave cosine synthesis of the input.
XT (input)
A work array.
MDIMX (input)
Leading dimension of the arrays X and XT as specified in a
dimension or type statement. MDIMX >= M.
WSAVE (input)
On entry, an array of dimension (2 * N + 15) or greater ini‐
tialized by VCOSQI.
6 Mar 2009 vdcosqb(3P)