uClibc now has a math library. muahahahaha!

 -Erik

1 files changed, 304 insertions, 0 deletions

diff --git a/libm/double/tan.c b/libm/double/tan.c
new file mode 100644
index 000000000..603f4b6a9
--- /dev/null
+++ b/libm/double/tan.c
@@ -0,0 +1,304 @@
+/*							tan.c
+ *
+ *	Circular tangent
+ *
+ *
+ *
+ * SYNOPSIS:
+ *
+ * double x, y, tan();
+ *
+ * y = tan( x );
+ *
+ *
+ *
+ * DESCRIPTION:
+ *
+ * Returns the circular tangent of the radian argument x.
+ *
+ * Range reduction is modulo pi/4.  A rational function
+ *       x + x**3 P(x**2)/Q(x**2)
+ * is employed in the basic interval [0, pi/4].
+ *
+ *
+ *
+ * ACCURACY:
+ *
+ *                      Relative error:
+ * arithmetic   domain     # trials      peak         rms
+ *    DEC      +-1.07e9      44000      4.1e-17     1.0e-17
+ *    IEEE     +-1.07e9      30000      2.9e-16     8.1e-17
+ *
+ * ERROR MESSAGES:
+ *
+ *   message         condition          value returned
+ * tan total loss   x > 1.073741824e9     0.0
+ *
+ */
+/*							cot.c
+ *
+ *	Circular cotangent
+ *
+ *
+ *
+ * SYNOPSIS:
+ *
+ * double x, y, cot();
+ *
+ * y = cot( x );
+ *
+ *
+ *
+ * DESCRIPTION:
+ *
+ * Returns the circular cotangent of the radian argument x.
+ *
+ * Range reduction is modulo pi/4.  A rational function
+ *       x + x**3 P(x**2)/Q(x**2)
+ * is employed in the basic interval [0, pi/4].
+ *
+ *
+ *
+ * ACCURACY:
+ *
+ *                      Relative error:
+ * arithmetic   domain     # trials      peak         rms
+ *    IEEE     +-1.07e9      30000      2.9e-16     8.2e-17
+ *
+ *
+ * ERROR MESSAGES:
+ *
+ *   message         condition          value returned
+ * cot total loss   x > 1.073741824e9       0.0
+ * cot singularity  x = 0                  INFINITY
+ *
+ */
+
+/*
+Cephes Math Library Release 2.8:  June, 2000
+yright 1984, 1995, 2000 by Stephen L. Moshier
+*/
+
+#include <math.h>
+
+#ifdef UNK
+static double P[] = {
+-1.30936939181383777646E4,
+ 1.15351664838587416140E6,
+-1.79565251976484877988E7
+};
+static double Q[] = {
+/* 1.00000000000000000000E0,*/
+ 1.36812963470692954678E4,
+-1.32089234440210967447E6,
+ 2.50083801823357915839E7,
+-5.38695755929454629881E7
+};
+static double DP1 = 7.853981554508209228515625E-1;
+static double DP2 = 7.94662735614792836714E-9;
+static double DP3 = 3.06161699786838294307E-17;
+static double lossth = 1.073741824e9;
+#endif
+
+#ifdef DEC
+static unsigned short P[] = {
+0143514,0113306,0111171,0174674,
+0045214,0147545,0027744,0167346,
+0146210,0177526,0114514,0105660
+};
+static unsigned short Q[] = {
+/*0040200,0000000,0000000,0000000,*/
+0043525,0142457,0072633,0025617,
+0145241,0036742,0140525,0162256,
+0046276,0146176,0013526,0143573,
+0146515,0077401,0162762,0150607
+};
+/*  7.853981629014015197753906250000E-1 */
+static unsigned short P1[] = {0040111,0007732,0120000,0000000,};
+/*  4.960467869796758577649598009884E-10 */
+static unsigned short P2[] = {0030410,0055060,0100000,0000000,};
+/*  2.860594363054915898381331279295E-18 */
+static unsigned short P3[] = {0021523,0011431,0105056,0001560,};
+#define DP1 *(double *)P1
+#define DP2 *(double *)P2
+#define DP3 *(double *)P3
+static double lossth = 1.073741824e9;
+#endif
+
+#ifdef IBMPC
+static unsigned short P[] = {
+0x3f38,0xd24f,0x92d8,0xc0c9,
+0x9ddd,0xa5fc,0x99ec,0x4131,
+0x9176,0xd329,0x1fea,0xc171
+};
+static unsigned short Q[] = {
+/*0x0000,0x0000,0x0000,0x3ff0,*/
+0x6572,0xeeb3,0xb8a5,0x40ca,
+0xbc96,0x582a,0x27bc,0xc134,
+0xd8ef,0xc2ea,0xd98f,0x4177,
+0x5a31,0x3cbe,0xafe0,0xc189
+};
+/*
+  7.85398125648498535156E-1,
+  3.77489470793079817668E-8,
+  2.69515142907905952645E-15,
+*/
+static unsigned short P1[] = {0x0000,0x4000,0x21fb,0x3fe9};
+static unsigned short P2[] = {0x0000,0x0000,0x442d,0x3e64};
+static unsigned short P3[] = {0x5170,0x98cc,0x4698,0x3ce8};
+#define DP1 *(double *)P1
+#define DP2 *(double *)P2
+#define DP3 *(double *)P3
+static double lossth = 1.073741824e9;
+#endif
+
+#ifdef MIEEE
+static unsigned short P[] = {
+0xc0c9,0x92d8,0xd24f,0x3f38,
+0x4131,0x99ec,0xa5fc,0x9ddd,
+0xc171,0x1fea,0xd329,0x9176
+};
+static unsigned short Q[] = {
+0x40ca,0xb8a5,0xeeb3,0x6572,
+0xc134,0x27bc,0x582a,0xbc96,
+0x4177,0xd98f,0xc2ea,0xd8ef,
+0xc189,0xafe0,0x3cbe,0x5a31
+};
+static unsigned short P1[] = {
+0x3fe9,0x21fb,0x4000,0x0000
+};
+static unsigned short P2[] = {
+0x3e64,0x442d,0x0000,0x0000
+};
+static unsigned short P3[] = {
+0x3ce8,0x4698,0x98cc,0x5170,
+};
+#define DP1 *(double *)P1
+#define DP2 *(double *)P2
+#define DP3 *(double *)P3
+static double lossth = 1.073741824e9;
+#endif
+
+#ifdef ANSIPROT
+extern double polevl ( double, void *, int );
+extern double p1evl ( double, void *, int );
+extern double floor ( double );
+extern double ldexp ( double, int );
+extern int isnan ( double );
+extern int isfinite ( double );
+static double tancot(double, int);
+#else
+double polevl(), p1evl(), floor(), ldexp();
+static double tancot();
+int isnan(), isfinite();
+#endif
+extern double PIO4;
+extern double INFINITY;
+extern double NAN;
+
+double tan(x)
+double x;
+{
+#ifdef MINUSZERO
+if( x == 0.0 )
+	return(x);
+#endif
+#ifdef NANS
+if( isnan(x) )
+	return(x);
+if( !isfinite(x) )
+	{
+	mtherr( "tan", DOMAIN );
+	return(NAN);
+	}
+#endif
+return( tancot(x,0) );
+}
+
+
+double cot(x)
+double x;
+{
+
+if( x == 0.0 )
+	{
+	mtherr( "cot", SING );
+	return( INFINITY );
+	}
+return( tancot(x,1) );
+}
+
+
+static double tancot( xx, cotflg )
+double xx;
+int cotflg;
+{
+double x, y, z, zz;
+int j, sign;
+
+/* make argument positive but save the sign */
+if( xx < 0 )
+	{
+	x = -xx;
+	sign = -1;
+	}
+else
+	{
+	x = xx;
+	sign = 1;
+	}
+
+if( x > lossth )
+	{
+	if( cotflg )
+		mtherr( "cot", TLOSS );
+	else
+		mtherr( "tan", TLOSS );
+	return(0.0);
+	}
+
+/* compute x mod PIO4 */
+y = floor( x/PIO4 );
+
+/* strip high bits of integer part */
+z = ldexp( y, -3 );
+z = floor(z);		/* integer part of y/8 */
+z = y - ldexp( z, 3 );  /* y - 16 * (y/16) */
+
+/* integer and fractional part modulo one octant */
+j = z;
+
+/* map zeros and singularities to origin */
+if( j & 1 )
+	{
+	j += 1;
+	y += 1.0;
+	}
+
+z = ((x - y * DP1) - y * DP2) - y * DP3;
+
+zz = z * z;
+
+if( zz > 1.0e-14 )
+	y = z  +  z * (zz * polevl( zz, P, 2 )/p1evl(zz, Q, 4));
+else
+	y = z;
+	
+if( j & 2 )
+	{
+	if( cotflg )
+		y = -y;
+	else
+		y = -1.0/y;
+	}
+else
+	{
+	if( cotflg )
+		y = 1.0/y;
+	}
+
+if( sign < 0 )
+	y = -y;
+
+return( y );
+}