/* $OpenBSD: n_sincos.c,v 1.9 2009/10/27 23:59:29 deraadt Exp $ */ /* $NetBSD: n_sincos.c,v 1.1 1995/10/10 23:37:04 ragge Exp $ */ /* * Copyright (c) 1987, 1993 * The Regents of the University of California. All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. Neither the name of the University nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ #include #include #include "mathimpl.h" double sin(double x) { double a,c,z; if(!finite(x)) /* sin(NaN) and sin(INF) must be NaN */ return x-x; x=remainder(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); } #ifdef __weak_alias __weak_alias(sinl, sin); #endif /* __weak_alias */ double cos(double x) { double a,c,z,s = 1.0; if(!finite(x)) /* cos(NaN) and cos(INF) must be NaN */ return x-x; x=remainder(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); } #ifdef __weak_alias __weak_alias(cosl, cos); #endif /* __weak_alias */