source: ttyvaders/trunk/libee/math.c @ 92

Last change on this file since 92 was 92, checked in by Sam Hocevar, 17 years ago
  • libee/math.c: fixed a thinko in ee_rand().
  • Property svn:keywords set to Id
File size: 1.4 KB
Line 
1/*
2 *   libee         ASCII-Art library
3 *   Copyright (c) 2002, 2003 Sam Hocevar <sam@zoy.org>
4 *                 All Rights Reserved
5 *
6 *   $Id: math.c 92 2003-11-09 13:51:37Z sam $
7 *
8 *   This program is free software; you can redistribute it and/or modify
9 *   it under the terms of the GNU General Public License as published by
10 *   the Free Software Foundation; either version 2 of the License, or
11 *   (at your option) any later version.
12 *
13 *   This program is distributed in the hope that it will be useful,
14 *   but WITHOUT ANY WARRANTY; without even the implied warranty of
15 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16 *   GNU General Public License for more details.
17 *
18 *   You should have received a copy of the GNU General Public License
19 *   along with this program; if not, write to the Free Software
20 *   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
21 */
22
23#include "config.h"
24
25#include <stdlib.h>
26
27#include "ee.h"
28
29int ee_rand(int min, int max)
30{
31    return min + (int)((1.0*(max-min+1)) * rand() / (RAND_MAX+1.0));
32}
33
34int ee_sqrt(int a)
35{
36    int x;
37
38    if(a <= 0)
39    {
40        return 0;
41    }
42
43    x = a > 100000 ? 1000 : a > 1000 ? 100 : a > 10 ? 10 : 1;
44
45    /* Newton's method. Three iterations would be more than enough. */
46    x = (x * x + a) / x / 2;
47    x = (x * x + a) / x / 2;
48    x = (x * x + a) / x / 2;
49    x = (x * x + a) / x / 2;
50
51    return x;
52}
53
Note: See TracBrowser for help on using the repository browser.