Totally rework the math library, this time based on the MacOs X

math library (which is itself based on the math lib from FreeBSD).
 -Erik

1 files changed, 0 insertions, 338 deletions

diff --git a/libm/float/powf.c b/libm/float/powf.c
deleted file mode 100644
index 367a39ad4..000000000
--- a/libm/float/powf.c
+++ /dev/null
@@ -1,338 +0,0 @@
-/*							powf.c
- *
- *	Power function
- *
- *
- *
- * SYNOPSIS:
- *
- * float x, y, z, powf();
- *
- * z = powf( x, y );
- *
- *
- *
- * DESCRIPTION:
- *
- * Computes x raised to the yth power.  Analytically,
- *
- *      x**y  =  exp( y log(x) ).
- *
- * Following Cody and Waite, this program uses a lookup table
- * of 2**-i/16 and pseudo extended precision arithmetic to
- * obtain an extra three bits of accuracy in both the logarithm
- * and the exponential.
- *
- *
- *
- * ACCURACY:
- *
- *                      Relative error:
- *  arithmetic  domain     # trials      peak         rms
- *    IEEE     -10,10      100,000      1.4e-7      3.6e-8
- * 1/10 < x < 10, x uniformly distributed.
- * -10 < y < 10, y uniformly distributed.
- *
- *
- * ERROR MESSAGES:
- *
- *   message         condition      value returned
- * powf overflow     x**y > MAXNUMF     MAXNUMF
- * powf underflow   x**y < 1/MAXNUMF      0.0
- * powf domain      x<0 and y noninteger  0.0
- *
- */
-
-/*
-Cephes Math Library Release 2.2:  June, 1992
-Copyright 1984, 1987, 1988 by Stephen L. Moshier
-Direct inquiries to 30 Frost Street, Cambridge, MA 02140
-*/
-
-
-#include <math.h>
-static char fname[] = {"powf"};
-
-
-/* 2^(-i/16)
- * The decimal values are rounded to 24-bit precision
- */
-static float A[] = {
-  1.00000000000000000000E0,
- 9.57603275775909423828125E-1,
- 9.17004048824310302734375E-1,
- 8.78126084804534912109375E-1,
- 8.40896427631378173828125E-1,
- 8.05245161056518554687500E-1,
- 7.71105408668518066406250E-1,
- 7.38413095474243164062500E-1,
- 7.07106769084930419921875E-1,
- 6.77127778530120849609375E-1,
- 6.48419797420501708984375E-1,
- 6.20928883552551269531250E-1,
- 5.94603538513183593750000E-1,
- 5.69394290447235107421875E-1,
- 5.45253872871398925781250E-1,
- 5.22136867046356201171875E-1,
-  5.00000000000000000000E-1
-};
-/* continuation, for even i only
- * 2^(i/16)  =  A[i] + B[i/2]
- */
-static float B[] = {
- 0.00000000000000000000E0,
--5.61963907099083340520586E-9,
--1.23776636307969995237668E-8,
- 4.03545234539989593104537E-9,
- 1.21016171044789693621048E-8,
--2.00949968760174979411038E-8,
- 1.89881769396087499852802E-8,
--6.53877009617774467211965E-9,
- 0.00000000000000000000E0
-};
-
-/* 1 / A[i]
- * The decimal values are full precision
- */
-static float Ainv[] = {
- 1.00000000000000000000000E0,
- 1.04427378242741384032197E0,
- 1.09050773266525765920701E0,
- 1.13878863475669165370383E0,
- 1.18920711500272106671750E0,
- 1.24185781207348404859368E0,
- 1.29683955465100966593375E0,
- 1.35425554693689272829801E0,
- 1.41421356237309504880169E0,
- 1.47682614593949931138691E0,
- 1.54221082540794082361229E0,
- 1.61049033194925430817952E0,
- 1.68179283050742908606225E0,
- 1.75625216037329948311216E0,
- 1.83400808640934246348708E0,
- 1.91520656139714729387261E0,
- 2.00000000000000000000000E0
-};
-
-#ifdef DEC
-#define MEXP 2032.0
-#define MNEXP -2032.0
-#else
-#define MEXP 2048.0
-#define MNEXP -2400.0
-#endif
-
-/* log2(e) - 1 */
-#define LOG2EA 0.44269504088896340736F
-extern float MAXNUMF;
-
-#define F W
-#define Fa Wa
-#define Fb Wb
-#define G W
-#define Ga Wa
-#define Gb u
-#define H W
-#define Ha Wb
-#define Hb Wb
-
-
-#ifdef ANSIC
-float floorf( float );
-float frexpf( float, int *);
-float ldexpf( float, int );
-float powif( float, int );
-#else
-float floorf(), frexpf(), ldexpf(), powif();
-#endif
-
-/* Find a multiple of 1/16 that is within 1/16 of x. */
-#define reduc(x)  0.0625 * floorf( 16 * (x) )
-
-#ifdef ANSIC
-float powf( float x, float y )
-#else
-float powf( x, y )
-float x, y;
-#endif
-{
-float u, w, z, W, Wa, Wb, ya, yb;
-/* float F, Fa, Fb, G, Ga, Gb, H, Ha, Hb */
-int e, i, nflg;
-
-
-nflg = 0;	/* flag = 1 if x<0 raised to integer power */
-w = floorf(y);
-if( w < 0 )
-	z = -w;
-else
-	z = w;
-if( (w == y) && (z < 32768.0) )
-	{
-	i = w;
-	w = powif( x, i );
-	return( w );
-	}
-
-
-if( x <= 0.0F )
-	{
-	if( x == 0.0 )
-		{
-		if( y == 0.0 )
-			return( 1.0 );  /*   0**0   */
-		else  
-			return( 0.0 );  /*   0**y   */
-		}
-	else
-		{
-		if( w != y )
-			{ /* noninteger power of negative number */
-			mtherr( fname, DOMAIN );
-			return(0.0);
-			}
-		nflg = 1;
-		if( x < 0 )
-			x = -x;
-		}
-	}
-
-/* separate significand from exponent */
-x = frexpf( x, &e );
-
-/* find significand in antilog table A[] */
-i = 1;
-if( x <= A[9] )
-	i = 9;
-if( x <= A[i+4] )
-	i += 4;
-if( x <= A[i+2] )
-	i += 2;
-if( x >= A[1] )
-	i = -1;
-i += 1;
-
-
-/* Find (x - A[i])/A[i]
- * in order to compute log(x/A[i]):
- *
- * log(x) = log( a x/a ) = log(a) + log(x/a)
- *
- * log(x/a) = log(1+v),  v = x/a - 1 = (x-a)/a
- */
-x -= A[i];
-x -= B[ i >> 1 ];
-x *= Ainv[i];
-
-
-/* rational approximation for log(1+v):
- *
- * log(1+v)  =  v  -  0.5 v^2  +  v^3 P(v)
- * Theoretical relative error of the approximation is 3.5e-11
- * on the interval 2^(1/16) - 1  > v > 2^(-1/16) - 1
- */
-z = x*x;
-w = (((-0.1663883081054895  * x
-      + 0.2003770364206271) * x
-      - 0.2500006373383951) * x
-      + 0.3333331095506474) * x * z;
-w -= 0.5 * z;
-
-/* Convert to base 2 logarithm:
- * multiply by log2(e)
- */
-w = w + LOG2EA * w;
-/* Note x was not yet added in
- * to above rational approximation,
- * so do it now, while multiplying
- * by log2(e).
- */
-z = w + LOG2EA * x;
-z = z + x;
-
-/* Compute exponent term of the base 2 logarithm. */
-w = -i;
-w *= 0.0625;  /* divide by 16 */
-w += e;
-/* Now base 2 log of x is w + z. */
-
-/* Multiply base 2 log by y, in extended precision. */
-
-/* separate y into large part ya
- * and small part yb less than 1/16
- */
-ya = reduc(y);
-yb = y - ya;
-
-
-F = z * y  +  w * yb;
-Fa = reduc(F);
-Fb = F - Fa;
-
-G = Fa + w * ya;
-Ga = reduc(G);
-Gb = G - Ga;
-
-H = Fb + Gb;
-Ha = reduc(H);
-w = 16 * (Ga + Ha);
-
-/* Test the power of 2 for overflow */
-if( w > MEXP )
-	{
-	mtherr( fname, OVERFLOW );
-	return( MAXNUMF );
-	}
-
-if( w < MNEXP )
-	{
-	mtherr( fname, UNDERFLOW );
-	return( 0.0 );
-	}
-
-e = w;
-Hb = H - Ha;
-
-if( Hb > 0.0 )
-	{
-	e += 1;
-	Hb -= 0.0625;
-	}
-
-/* Now the product y * log2(x)  =  Hb + e/16.0.
- *
- * Compute base 2 exponential of Hb,
- * where -0.0625 <= Hb <= 0.
- * Theoretical relative error of the approximation is 2.8e-12.
- */
-/*  z  =  2**Hb - 1    */
-z = ((( 9.416993633606397E-003 * Hb
-      + 5.549356188719141E-002) * Hb
-      + 2.402262883964191E-001) * Hb
-      + 6.931471791490764E-001) * Hb;
-
-/* Express e/16 as an integer plus a negative number of 16ths.
- * Find lookup table entry for the fractional power of 2.
- */
-if( e < 0 )
-	i = -( -e >> 4 );
-else
-	i = (e >> 4) + 1;
-e = (i << 4) - e;
-w = A[e];
-z = w + w * z;      /*    2**-e * ( 1 + (2**Hb-1) )    */
-z = ldexpf( z, i );  /* multiply by integer power of 2 */
-
-if( nflg )
-	{
-/* For negative x,
- * find out if the integer exponent
- * is odd or even.
- */
-	w = 2 * floorf( (float) 0.5 * w );
-	if( w != y )
-		z = -z; /* odd exponent */
-	}
-
-return( z );
-}