POK
gammaf.c
1 /*
2  * POK header
3  *
4  * The following file is a part of the POK project. Any modification should
5  * made according to the POK licence. You CANNOT use this file or a part of
6  * this file is this part of a file for your own project
7  *
8  * For more information on the POK licence, please see our LICENCE FILE
9  *
10  * Please follow the coding guidelines described in doc/CODING_GUIDELINES
11  *
12  * Copyright (c) 2007-2009 POK team
13  *
14  * Created by julien on Fri Jan 30 14:41:34 2009
15  */
16 
17 /* w_gammaf.c -- float version of w_gamma.c.
18  * Conversion to float by Ian Lance Taylor, Cygnus Support, ian@cygnus.com.
19  */
20 
21 /*
22  * ====================================================
23  * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
24  *
25  * Developed at SunPro, a Sun Microsystems, Inc. business.
26  * Permission to use, copy, modify, and distribute this
27  * software is freely granted, provided that this notice
28  * is preserved.
29  * ====================================================
30  */
31 
32 #ifdef POK_NEEDS_LIBMATH
33 
34 #include <libm.h>
35 #include "math_private.h"
36 
37 float
38 gammaf(float x)
39 {
40 #ifdef _IEEE_LIBM
41  return __ieee754_lgammaf_r(x,&signgam);
42 #else
43  float y;
44  y = __ieee754_lgammaf_r(x,&signgam);
45  if(_LIB_VERSION == _IEEE_) return y;
46  if(!finitef(y)&&finitef(x)) {
47  if(floorf(x)==x&&x<=(float)0.0)
48  /* gammaf pole */
49  return (float)__kernel_standard((double)x,(double)x,141);
50  else
51  /* gammaf overflow */
52  return (float)__kernel_standard((double)x,(double)x,140);
53  } else
54  return y;
55 #endif
56 }
57 
58 #endif