1/* e_acoshf.c -- float version of e_acosh.c.
2 * Conversion to float by Ian Lance Taylor, Cygnus Support, ian@cygnus.com.
3 */
4
5/*
6 * ====================================================
7 * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
8 *
9 * Developed at SunPro, a Sun Microsystems, Inc. business.
10 * Permission to use, copy, modify, and distribute this
11 * software is freely granted, provided that this notice
12 * is preserved.
13 * ====================================================
14 */
15
| 1/* e_acoshf.c -- float version of e_acosh.c.
2 * Conversion to float by Ian Lance Taylor, Cygnus Support, ian@cygnus.com.
3 */
4
5/*
6 * ====================================================
7 * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
8 *
9 * Developed at SunPro, a Sun Microsystems, Inc. business.
10 * Permission to use, copy, modify, and distribute this
11 * software is freely granted, provided that this notice
12 * is preserved.
13 * ====================================================
14 */
15
|
19
20#include "math.h"
21#include "math_private.h"
22
23static const float
24one = 1.0,
25ln2 = 6.9314718246e-01; /* 0x3f317218 */
26
27float
28__ieee754_acoshf(float x)
29{
30 float t;
31 int32_t hx;
32 GET_FLOAT_WORD(hx,x);
33 if(hx<0x3f800000) { /* x < 1 */
34 return (x-x)/(x-x);
35 } else if(hx >=0x4d800000) { /* x > 2**28 */
36 if(hx >=0x7f800000) { /* x is inf of NaN */
37 return x+x;
38 } else
39 return __ieee754_logf(x)+ln2; /* acosh(huge)=log(2x) */
40 } else if (hx==0x3f800000) {
41 return 0.0; /* acosh(1) = 0 */
42 } else if (hx > 0x40000000) { /* 2**28 > x > 2 */
43 t=x*x;
44 return __ieee754_logf((float)2.0*x-one/(x+__ieee754_sqrtf(t-one)));
45 } else { /* 1<x<2 */
46 t = x-one;
47 return log1pf(t+__ieee754_sqrtf((float)2.0*t+t*t));
48 }
49}
| 18
19#include "math.h"
20#include "math_private.h"
21
22static const float
23one = 1.0,
24ln2 = 6.9314718246e-01; /* 0x3f317218 */
25
26float
27__ieee754_acoshf(float x)
28{
29 float t;
30 int32_t hx;
31 GET_FLOAT_WORD(hx,x);
32 if(hx<0x3f800000) { /* x < 1 */
33 return (x-x)/(x-x);
34 } else if(hx >=0x4d800000) { /* x > 2**28 */
35 if(hx >=0x7f800000) { /* x is inf of NaN */
36 return x+x;
37 } else
38 return __ieee754_logf(x)+ln2; /* acosh(huge)=log(2x) */
39 } else if (hx==0x3f800000) {
40 return 0.0; /* acosh(1) = 0 */
41 } else if (hx > 0x40000000) { /* 2**28 > x > 2 */
42 t=x*x;
43 return __ieee754_logf((float)2.0*x-one/(x+__ieee754_sqrtf(t-one)));
44 } else { /* 1<x<2 */
45 t = x-one;
46 return log1pf(t+__ieee754_sqrtf((float)2.0*t+t*t));
47 }
48}
|