source: trunk/sys/libm/w_pow.c @ 233

Last change on this file since 233 was 1, checked in by alain, 7 years ago

First import

File size: 1.4 KB
Line 
1
2
3/* @(#)w_pow.c 5.2 93/10/01 */
4/*
5 * ====================================================
6 * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
7 *
8 * Developed at SunPro, a Sun Microsystems, Inc. business.
9 * Permission to use, copy, modify, and distribute this
10 * software is freely granted, provided that this notice
11 * is preserved.
12 * ====================================================
13 */
14
15/*
16 * wrapper pow(x,y) return x**y
17 */
18
19#include <libm/fdlibm.h>
20
21
22#ifdef __STDC__
23        double pow(double x, double y)  /* wrapper pow */
24#else
25        double pow(x,y)                 /* wrapper pow */
26        double x,y;
27#endif
28{
29#ifdef _IEEE_LIBM
30        return  __ieee754_pow(x,y);
31#else
32        double z;
33        z=__ieee754_pow(x,y);
34        if(_LIB_VERSION == _IEEE_|| isnan(y)) return z;
35        if(isnan(x)) {
36            if(y==0.0) 
37                return __kernel_standard(x,y,42); /* pow(NaN,0.0) */
38            else 
39                return z;
40        }
41        if(x==0.0){ 
42            if(y==0.0)
43                return __kernel_standard(x,y,20); /* pow(0.0,0.0) */
44            if(finite(y)&&y<0.0)
45                return __kernel_standard(x,y,23); /* pow(0.0,negative) */
46            return z;
47        }
48        if(!finite(z)) {
49            if(finite(x)&&finite(y)) {
50                if(isnan(z))
51                    return __kernel_standard(x,y,24); /* pow neg**non-int */
52                else 
53                    return __kernel_standard(x,y,21); /* pow overflow */
54            }
55        } 
56        if(z==0.0&&finite(x)&&finite(y))
57            return __kernel_standard(x,y,22); /* pow underflow */
58        return z;
59#endif
60}
Note: See TracBrowser for help on using the repository browser.