blob: 2a6b5b40213e1d894403aa95a94ec7aa680f0b6a (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
|
/* @(#)s_fabs.c 5.1 93/09/24 */
/*
* ====================================================
* Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
*
* Developed at SunPro, a Sun Microsystems, Inc. business.
* Permission to use, copy, modify, and distribute this
* software is freely granted, provided that this notice
* is preserved.
* ====================================================
*/
/*
FUNCTION
<<fabs>>, <<fabsf>>---absolute value (magnitude)
INDEX
fabs
INDEX
fabsf
SYNOPSIS
#include <math.h>
double fabs(double <[x]>);
float fabsf(float <[x]>);
DESCRIPTION
<<fabs>> and <<fabsf>> calculate
@tex
$|x|$,
@end tex
the absolute value (magnitude) of the argument <[x]>, by direct
manipulation of the bit representation of <[x]>.
RETURNS
The calculated value is returned. No errors are detected.
PORTABILITY
<<fabs>> is ANSI.
<<fabsf>> is an extension.
*/
/*
* fabs(x) returns the absolute value of x.
*/
#include "fdlibm.h"
#ifndef _DOUBLE_IS_32BITS
#ifdef __STDC__
double fabs(double x)
#else
double fabs(x)
double x;
#endif
{
__uint32_t high;
GET_HIGH_WORD(high,x);
SET_HIGH_WORD(x,high&0x7fffffff);
return x;
}
#endif /* _DOUBLE_IS_32BITS */
|
