2 * Copyright Droids Corporation, Microb Technology, Eirbot (2005)
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License as published by
6 * the Free Software Foundation; either version 2 of the License, or
7 * (at your option) any later version.
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
14 * You should have received a copy of the GNU General Public License
15 * along with this program; if not, write to the Free Software
16 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
18 * Revision : $Id: f16_sqrt.c,v 1.5.4.4 2009-02-02 22:21:20 zer0 Exp $
24 #include <s16_to_f16.h>
27 #define NEXT(n, i) (((n) + (i)/(n)) >> 1)
29 static uint16_t u16_sqrt(uint16_t number) {
31 uint16_t n1 = NEXT(n, number);
36 while(ABS(n1 - n) > 1) {
40 while((n1*n1) > number) {
55 /* sqrt(a+b) = sqrt(a)*sqrt(1+b/a) */
56 a=(uint16_t)(f.f16_integer) << 8 ;
57 b=(uint16_t)(f.f16_decimal) << 8 ;
59 d=u16_sqrt(0x100 + (b/a));
60 return f16_mul(s16_to_f16( c<<4 ), s16_to_f16( d<<4 ));
63 b=(uint16_t)(f.f16_decimal) << 8 ;
64 return s16_to_f16(u16_sqrt(b));