*** empty log message ***

1984-11-29 14:22:02 +00:00
parent 0c0c3b7892
commit ae1e81adb1
36 changed files with 1740 additions and 0 deletions
--- a/lang/basic/lib/sin.c
+++ b/lang/basic/lib/sin.c
@@ -0,0 +1,102 @@
+/*
+ * (c) copyright 1983 by the Vrije Universiteit, Amsterdam, The Netherlands.
+ *
+ *          This product is part of the Amsterdam Compiler Kit.
+ *
+ * Permission to use, sell, duplicate or disclose this software must be
+ * obtained in writing. Requests for such permissions may be sent to
+ *
+ *      Dr. Andrew S. Tanenbaum
+ *      Wiskundig Seminarium
+ *      Vrije Universiteit
+ *      Postbox 7161
+ *      1007 MC Amsterdam
+ *      The Netherlands
+ *
+ */
+
+/* $Header $ */
+
+/* Author: J.W. Stevenson */
+
+extern double	_fif();
+
+/*
+	C program for floating point sin/cos.
+	Calls _fif.
+	There are no error exits.
+	Coefficients are #3370 from Hart & Cheney (18.80D).
+*/
+
+static double twoopi	= 0.63661977236758134308;
+static double p0	=  .1357884097877375669092680e8;
+static double p1	= -.4942908100902844161158627e7;
+static double p2	=  .4401030535375266501944918e6;
+static double p3	= -.1384727249982452873054457e5;
+static double p4	=  .1459688406665768722226959e3;
+static double q0	=  .8644558652922534429915149e7;
+static double q1	=  .4081792252343299749395779e6;
+static double q2	=  .9463096101538208180571257e4;
+static double q3	=  .1326534908786136358911494e3;
+
+static double
+sinus(arg, quad)
+double arg;
+int quad;
+{
+	double e, f;
+	double ysq;
+	double x,y;
+	int k;
+	double temp1, temp2;
+
+	x = arg;
+	if(x<0) {
+		x = -x;
+		quad = quad + 2;
+	}
+	x = x*twoopi;	/*underflow?*/
+	if(x>32764){
+		y = _fif(x, 10.0, &e);
+		e = e + quad;
+		_fif(0.25, e, &f);
+		quad = e - 4*f;
+	}else{
+		k = x;
+		y = x - k;
+		quad = (quad + k) & 03;
+	}
+	if (quad & 01)
+		y = 1-y;
+	if(quad > 1)
+		y = -y;
+
+	ysq = y*y;
+	temp1 = ((((p4*ysq+p3)*ysq+p2)*ysq+p1)*ysq+p0)*y;
+	temp2 = ((((ysq+q3)*ysq+q2)*ysq+q1)*ysq+q0);
+	return(temp1/temp2);
+}
+
+double
+_cos(arg)
+double arg;
+{
+	if(arg<0)
+		arg = -arg;
+	return(sinus(arg, 1));
+}
+
+double
+_sin(arg)
+double arg;
+{
+	return(sinus(arg, 0));
+}
+
+/* EXTENSION */
+double
+_tan(arg)
+double arg;
+{
+	return( _sin(arg)/_cos(arg));
+}