/* sincos.c - math routines *//* Copyright 1992-1993 Wind River Systems, Inc. *//*modification history--------------------01f,05feb93,jdi  doc changes based on kdl review.01e,02dec92,jdi  doc tweaks.01d,28oct92,jdi  documentation cleanup.01c,21sep92,smb  changed function headers for mg.01b,20sep92,smb  documentation additions01a,08jul92,smb  documentation.*//*DESCRIPTION* Copyright (c) 1987 Regents of the University of California.* All rights reserved.** Redistribution and use in source and binary forms are permitted* provided that the above copyright notice and this paragraph are* duplicated in all such forms and that any documentation,* advertising materials, and other materials related to such* distribution and use acknowledge that the software was developed* by the University of California, Berkeley.  The name of the* University may not be used to endorse or promote products derived* from this software without specific prior written permission.* THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR* IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED* WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.** All recipients should regard themselves as participants in an ongoing* research project and hence should feel obligated to report their* experiences (good or bad) with these elementary function codes, using* the sendbug(8) program, to the authors.*SEE ALSO: American National Standard X3.159-1989NOMANUAL*/#include "vxWorks.h"#include "math.h"#include "private/trigP.h"/********************************************************************************* sin - compute a sine (ANSI)** This routine computes the sine of <x> in double precision.* The angle <x> is expressed in radians.** INCLUDE FILES: math.h** RETURNS: The double-precision sine of <x>.** SEE ALSO: mathALib*/double sin    (    double x	/* angle in radians */    )    {	double a,c,z;        if(!finite(x))		/* sin(NaN) and sin(INF) must be NaN */		return x-x;	x=drem(x,PI2);		/* reduce x into [-PI,PI] */	a=copysign(x,one);	if (a >= PIo4) {		if(a >= PI3o4)		/* ... in [3PI/4,PI] */			x = copysign((a = PI-a),x);		else {			/* ... in [PI/4,3PI/4]  */			a = PIo2-a;		/* rtn. sign(x)*C(PI/2-|x|) */			z = a*a;			c = cos__C(z);			z *= half;			a = (z >= thresh ? half-((z-half)-c) : one-(z-c));			return copysign(a,x);		}	}	if (a < small) {		/* rtn. S(x) */		big+a;		return x;	}	return x+x*sin__S(x*x);    }/********************************************************************************* cos - compute a cosine (ANSI)** This routine computes the cosine of <x> in double precision.* The angle <x> is expressed in radians.** INCLUDE FILES: math.h** RETURNS: The double-precision cosine of <x>.** SEE ALSO: mathALib*/double cos    (    double x	/* angle in radians */    )    {	double a,c,z,s = 1.0;	if(!finite(x))		/* cos(NaN) and cos(INF) must be NaN */		return x-x;	x=drem(x,PI2);		/* reduce x into [-PI,PI] */	a=copysign(x,one);	if (a >= PIo4) {		if (a >= PI3o4) {	/* ... in [3PI/4,PI] */			a = PI-a;			s = negone;		}		else {			/* ... in [PI/4,3PI/4] */			a = PIo2-a;			return a+a*sin__S(a*a);	/* rtn. S(PI/2-|x|) */		}	}	if (a < small) {		big+a;		return s;		/* rtn. s*C(a) */	}	z = a*a;	c = cos__C(z);	z *= half;	a = (z >= thresh ? half-((z-half)-c) : one-(z-c));	return copysign(a,s);    }