37 lines
1.1 KiB
C
37 lines
1.1 KiB
C
|
|
||
|
|
/* @(#)k_cos.c 1.3 95/01/18 */
|
||
|
|
/*
|
||
|
|
* ====================================================
|
||
|
|
* Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
|
||
|
|
*
|
||
|
|
* Developed at SunSoft, a Sun Microsystems, Inc. business.
|
||
|
|
* Permission to use, copy, modify, and distribute this
|
||
|
|
* software is freely granted, provided that this notice
|
||
|
|
* is preserved.
|
||
|
|
* ====================================================
|
||
|
|
*/
|
||
|
|
|
||
|
|
#include "math.h"
|
||
|
|
#include "math_private.h"
|
||
|
|
|
||
|
|
static const double
|
||
|
|
one = 1.00000000000000000000e+00, /* 0x3FF00000, 0x00000000 */
|
||
|
|
C1 = 4.16666666666666019037e-02, /* 0x3FA55555, 0x5555554C */
|
||
|
|
C2 = -1.38888888888741095749e-03, /* 0xBF56C16C, 0x16C15177 */
|
||
|
|
C3 = 2.48015872894767294178e-05, /* 0x3EFA01A0, 0x19CB1590 */
|
||
|
|
C4 = -2.75573143513906633035e-07, /* 0xBE927E4F, 0x809C52AD */
|
||
|
|
C5 = 2.08757232129817482790e-09, /* 0x3E21EE9E, 0xBDB4B1C4 */
|
||
|
|
C6 = -1.13596475577881948265e-11; /* 0xBDA8FAE9, 0xBE8838D4 */
|
||
|
|
|
||
|
|
double __kernel_cos(double x, double y)
|
||
|
|
{
|
||
|
|
double hz,z,r,w;
|
||
|
|
|
||
|
|
z = x*x;
|
||
|
|
w = z*z;
|
||
|
|
r = z*(C1+z*(C2+z*C3)) + w*w*(C4+z*(C5+z*C6));
|
||
|
|
hz = 0.5*z;
|
||
|
|
w = one-hz;
|
||
|
|
return w + (((one-w)-hz) + (z*r-x*y));
|
||
|
|
}
|