From 28f540f45bbacd939bfd07f213bcad2bf730b1bf Mon Sep 17 00:00:00 2001
From: Roland McGrath <roland@gnu.org>
Date: Sat, 18 Feb 1995 01:27:10 +0000
Subject: initial import

---
 sysdeps/generic/sincos.c | 98 ++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 98 insertions(+)
 create mode 100644 sysdeps/generic/sincos.c

(limited to 'sysdeps/generic/sincos.c')

diff --git a/sysdeps/generic/sincos.c b/sysdeps/generic/sincos.c
new file mode 100644
index 0000000000..ab885607cf
--- /dev/null
+++ b/sysdeps/generic/sincos.c
@@ -0,0 +1,98 @@
+/*
+ * 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. All advertising materials mentioning features or use of this software
+ *    must display the following acknowledgement:
+ *	This product includes software developed by the University of
+ *	California, Berkeley and its contributors.
+ * 4. 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.
+ */
+
+#ifndef lint
+static char sccsid[] = "@(#)sincos.c	8.1 (Berkeley) 6/4/93";
+#endif /* not lint */
+
+#include "trig.h"
+double
+sin(x)
+double x;
+{
+	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);
+}
+
+double
+cos(x) 
+double x;
+{
+	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);
+}
-- 
cgit 1.4.1