Remove trailing white space.
[glibc.git] / math / s_catanhf.c
blob0e55aff16cb7ec8bbf09a16e739ccda820098da2
1 /* Return arc hyperbole tangent for float value.
2 Copyright (C) 1997-2014 Free Software Foundation, Inc.
3 This file is part of the GNU C Library.
4 Contributed by Ulrich Drepper <drepper@cygnus.com>, 1997.
6 The GNU C Library is free software; you can redistribute it and/or
7 modify it under the terms of the GNU Lesser General Public
8 License as published by the Free Software Foundation; either
9 version 2.1 of the License, or (at your option) any later version.
11 The GNU C Library is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 Lesser General Public License for more details.
16 You should have received a copy of the GNU Lesser General Public
17 License along with the GNU C Library; if not, see
18 <http://www.gnu.org/licenses/>. */
20 #include <complex.h>
21 #include <math.h>
22 #include <math_private.h>
23 #include <float.h>
25 __complex__ float
26 __catanhf (__complex__ float x)
28 __complex__ float res;
29 int rcls = fpclassify (__real__ x);
30 int icls = fpclassify (__imag__ x);
32 if (__glibc_unlikely (rcls <= FP_INFINITE || icls <= FP_INFINITE))
34 if (icls == FP_INFINITE)
36 __real__ res = __copysignf (0.0, __real__ x);
37 __imag__ res = __copysignf (M_PI_2, __imag__ x);
39 else if (rcls == FP_INFINITE || rcls == FP_ZERO)
41 __real__ res = __copysignf (0.0, __real__ x);
42 if (icls >= FP_ZERO)
43 __imag__ res = __copysignf (M_PI_2, __imag__ x);
44 else
45 __imag__ res = __nanf ("");
47 else
49 __real__ res = __nanf ("");
50 __imag__ res = __nanf ("");
53 else if (__glibc_unlikely (rcls == FP_ZERO && icls == FP_ZERO))
55 res = x;
57 else
59 if (fabsf (__real__ x) >= 16.0f / FLT_EPSILON
60 || fabsf (__imag__ x) >= 16.0f / FLT_EPSILON)
62 __imag__ res = __copysignf ((float) M_PI_2, __imag__ x);
63 if (fabsf (__imag__ x) <= 1.0f)
64 __real__ res = 1.0f / __real__ x;
65 else if (fabsf (__real__ x) <= 1.0f)
66 __real__ res = __real__ x / __imag__ x / __imag__ x;
67 else
69 float h = __ieee754_hypotf (__real__ x / 2.0f,
70 __imag__ x / 2.0f);
71 __real__ res = __real__ x / h / h / 4.0f;
74 else
76 if (fabsf (__real__ x) == 1.0f
77 && fabsf (__imag__ x) < FLT_EPSILON * FLT_EPSILON)
78 __real__ res = (__copysignf (0.5f, __real__ x)
79 * ((float) M_LN2
80 - __ieee754_logf (fabsf (__imag__ x))));
81 else
83 float i2 = 0.0f;
84 if (fabsf (__imag__ x) >= FLT_EPSILON * FLT_EPSILON)
85 i2 = __imag__ x * __imag__ x;
87 float num = 1.0f + __real__ x;
88 num = i2 + num * num;
90 float den = 1.0f - __real__ x;
91 den = i2 + den * den;
93 float f = num / den;
94 if (f < 0.5f)
95 __real__ res = 0.25f * __ieee754_logf (f);
96 else
98 num = 4.0f * __real__ x;
99 __real__ res = 0.25f * __log1pf (num / den);
103 float absx, absy, den;
105 absx = fabsf (__real__ x);
106 absy = fabsf (__imag__ x);
107 if (absx < absy)
109 float t = absx;
110 absx = absy;
111 absy = t;
114 if (absy < FLT_EPSILON / 2.0f)
116 den = (1.0f - absx) * (1.0f + absx);
117 if (den == -0.0f)
118 den = 0.0f;
120 else if (absx >= 1.0f)
121 den = (1.0f - absx) * (1.0f + absx) - absy * absy;
122 else if (absx >= 0.75f || absy >= 0.5f)
123 den = -__x2y2m1f (absx, absy);
124 else
125 den = (1.0f - absx) * (1.0f + absx) - absy * absy;
127 __imag__ res = 0.5f * __ieee754_atan2f (2.0f * __imag__ x, den);
130 if (fabsf (__real__ res) < FLT_MIN)
132 volatile float force_underflow = __real__ res * __real__ res;
133 (void) force_underflow;
135 if (fabsf (__imag__ res) < FLT_MIN)
137 volatile float force_underflow = __imag__ res * __imag__ res;
138 (void) force_underflow;
142 return res;
144 #ifndef __catanhf
145 weak_alias (__catanhf, catanhf)
146 #endif