add directory gnu

gnu/glibc/glibc-1.03/math/bsd/common/sincos.c

@@ -0,0 +1,84 @@
+/*
+ * Copyright (c) 1987 Regents of the University of California.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms are permitted provided
+ * that: (1) source distributions retain this entire copyright notice and
+ * comment, and (2) distributions including binaries display the following
+ * acknowledgement:  ``This product includes software developed by the
+ * University of California, Berkeley and its contributors'' in the
+ * documentation or other materials provided with the distribution and in
+ * all advertising materials mentioning features or use of this software.
+ * 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 ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
+ */
+
+#ifndef lint
+static char sccsid[] = "@(#)sincos.c	5.5 (Berkeley) 10/9/90";
+#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);
+}