NetBSD/lib/libm/ld128/k_sinl.c

58 lines
1.9 KiB
C

/* From: @(#)k_sin.c 1.3 95/01/18 */
/*
* ====================================================
* Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
* Copyright (c) 2008 Steven G. Kargl, David Schultz, Bruce D. Evans.
*
* 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 <sys/cdefs.h>
/*
* ld128 version of k_sin.c. See ../src/k_sin.c for most comments.
*/
#include "math_private.h"
static const double
half = 0.5;
/*
* Domain [-0.7854, 0.7854], range ~[-1.53e-37, 1.659e-37]
* |sin(x)/x - s(x)| < 2**-122.1
*
* See ../ld80/k_cosl.c for more details about the polynomial.
*/
static const long double
S1 = -0.16666666666666666666666666666666666606732416116558L,
S2 = 0.0083333333333333333333333333333331135404851288270047L,
S3 = -0.00019841269841269841269841269839935785325638310428717L,
S4 = 0.27557319223985890652557316053039946268333231205686e-5L,
S5 = -0.25052108385441718775048214826384312253862930064745e-7L,
S6 = 0.16059043836821614596571832194524392581082444805729e-9L,
S7 = -0.76471637318198151807063387954939213287488216303768e-12L,
S8 = 0.28114572543451292625024967174638477283187397621303e-14L;
static const double
S9 = -0.82206352458348947812512122163446202498005154296863e-17,
S10 = 0.19572940011906109418080609928334380560135358385256e-19,
S11 = -0.38680813379701966970673724299207480965452616911420e-22,
S12 = 0.64038150078671872796678569586315881020659912139412e-25;
long double
__kernel_sinl(long double x, long double y, int iy)
{
long double z,r,v;
z = x*x;
v = z*x;
r = S2+z*(S3+z*(S4+z*(S5+z*(S6+z*(S7+z*(S8+
z*(S9+z*(S10+z*(S11+z*S12)))))))));
if(iy==0) return x+v*(S1+z*r);
else return x-((z*(half*y-v*r)-y)-v*S1);
}