diff options
Diffstat (limited to 'libm/float/sqrtf.c')
| -rw-r--r-- | libm/float/sqrtf.c | 140 | 
1 files changed, 0 insertions, 140 deletions
diff --git a/libm/float/sqrtf.c b/libm/float/sqrtf.c deleted file mode 100644 index bc75a907b..000000000 --- a/libm/float/sqrtf.c +++ /dev/null @@ -1,140 +0,0 @@ -/*							sqrtf.c - * - *	Square root - * - * - * - * SYNOPSIS: - * - * float x, y, sqrtf(); - * - * y = sqrtf( x ); - * - * - * - * DESCRIPTION: - * - * Returns the square root of x. - * - * Range reduction involves isolating the power of two of the - * argument and using a polynomial approximation to obtain - * a rough value for the square root.  Then Heron's iteration - * is used three times to converge to an accurate value. - * - * - * - * ACCURACY: - * - * - *                      Relative error: - * arithmetic   domain     # trials      peak         rms - *    IEEE      0,1.e38     100000       8.7e-8     2.9e-8 - * - * - * ERROR MESSAGES: - * - *   message         condition      value returned - * sqrtf domain        x < 0            0.0 - * - */ - -/* -Cephes Math Library Release 2.2:  June, 1992 -Copyright 1984, 1987, 1988, 1992 by Stephen L. Moshier -Direct inquiries to 30 Frost Street, Cambridge, MA 02140 -*/ - -/* Single precision square root - * test interval: [sqrt(2)/2, sqrt(2)] - * trials: 30000 - * peak relative error: 8.8e-8 - * rms relative error: 3.3e-8 - * - * test interval: [0.01, 100.0] - * trials: 50000 - * peak relative error: 8.7e-8 - * rms relative error: 3.3e-8 - * - * Copyright (C) 1989 by Stephen L. Moshier.  All rights reserved. - */ -#include <math.h> - -#ifdef ANSIC -float frexpf( float, int * ); -float ldexpf( float, int ); - -float sqrtf( float xx ) -#else -float frexpf(), ldexpf(); - -float sqrtf(xx) -float xx; -#endif -{ -float f, x, y; -int e; - -f = xx; -if( f <= 0.0 ) -	{ -	if( f < 0.0 ) -		mtherr( "sqrtf", DOMAIN ); -	return( 0.0 ); -	} - -x = frexpf( f, &e );	/* f = x * 2**e,   0.5 <= x < 1.0 */ -/* If power of 2 is odd, double x and decrement the power of 2. */ -if( e & 1 ) -	{ -	x = x + x; -	e -= 1; -	} - -e >>= 1;	/* The power of 2 of the square root. */ - -if( x > 1.41421356237 ) -	{ -/* x is between sqrt(2) and 2. */ -	x = x - 2.0; -	y = -	((((( -9.8843065718E-4 * x -	  + 7.9479950957E-4) * x -	  - 3.5890535377E-3) * x -	  + 1.1028809744E-2) * x -	  - 4.4195203560E-2) * x -	  + 3.5355338194E-1) * x -	  + 1.41421356237E0; -	goto sqdon; -	} - -if( x > 0.707106781187 ) -	{ -/* x is between sqrt(2)/2 and sqrt(2). */ -	x = x - 1.0; -	y = -	((((( 1.35199291026E-2 * x -	  - 2.26657767832E-2) * x -	  + 2.78720776889E-2) * x -	  - 3.89582788321E-2) * x -	  + 6.24811144548E-2) * x -	  - 1.25001503933E-1) * x * x -	  + 0.5 * x -	  + 1.0; -	goto sqdon; -	} - -/* x is between 0.5 and sqrt(2)/2. */ -x = x - 0.5; -y = -((((( -3.9495006054E-1 * x -  + 5.1743034569E-1) * x -  - 4.3214437330E-1) * x -  + 3.5310730460E-1) * x -  - 3.5354581892E-1) * x -  + 7.0710676017E-1) * x -  + 7.07106781187E-1; - -sqdon: -y = ldexpf( y, e );  /* y = y * 2**e */ -return( y); -}  | 
