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annotate lib/tanl.c @ 17249:e542fd46ad6f

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maint: update all copyright year number ranges Run "make update-copyright". Compare to commit 1602f0a from last year. Signed-off-by: Eric Blake <eblake@redhat.com>
author Eric Blake <eblake@redhat.com>
date Tue, 01 Jan 2013 00:50:58 +0000
parents 2074f2bf7216
children
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1 /* s_tanl.c -- long double version of s_tan.c.
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2 * Conversion to IEEE quad long double by Jakub Jelinek, jj@ultra.linux.cz.
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3 */
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4
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5 /* @(#)s_tan.c 5.1 93/09/24 */
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6 /*
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7 * ====================================================
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8 * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
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9 *
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10 * Developed at SunPro, a Sun Microsystems, Inc. business.
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11 * Permission to use, copy, modify, and distribute this
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12 * software is freely granted, provided that this notice
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13 * is preserved.
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14 * ====================================================
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15 */
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16
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17 #include <config.h>
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18
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19 /* Specification. */
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20 #include <math.h>
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21
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22 #if HAVE_SAME_LONG_DOUBLE_AS_DOUBLE
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23
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24 long double
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25 tanl (long double x)
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26 {
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27 return tan (x);
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28 }
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29
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30 #else
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31
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32 /* Code based on glibc/sysdeps/ieee754/ldbl-128/s_tanl.c
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33 and glibc/sysdeps/ieee754/ldbl-128/k_tanl.c. */
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34
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35 /* tanl(x)
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36 * Return tangent function of x.
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37 *
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38 * kernel function:
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39 * __kernel_tanl ... tangent function on [-pi/4,pi/4]
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40 * __ieee754_rem_pio2l ... argument reduction routine
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41 *
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42 * Method.
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43 * Let S,C and T denote the sin, cos and tan respectively on
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44 * [-PI/4, +PI/4]. Reduce the argument x to y1+y2 = x-k*pi/2
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45 * in [-pi/4 , +pi/4], and let n = k mod 4.
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46 * We have
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47 *
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48 * n sin(x) cos(x) tan(x)
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49 * ----------------------------------------------------------
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50 * 0 S C T
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51 * 1 C -S -1/T
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52 * 2 -S -C T
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53 * 3 -C S -1/T
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54 * ----------------------------------------------------------
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55 *
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56 * Special cases:
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57 * Let trig be any of sin, cos, or tan.
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58 * trig(+-INF) is NaN, with signals;
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59 * trig(NaN) is that NaN;
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60 *
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61 * Accuracy:
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62 * TRIG(x) returns trig(x) nearly rounded
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63 */
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64
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65 # include "trigl.h"
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66
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67 /*
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68 * ====================================================
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69 * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
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70 *
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71 * Developed at SunPro, a Sun Microsystems, Inc. business.
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72 * Permission to use, copy, modify, and distribute this
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73 * software is freely granted, provided that this notice
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74 * is preserved.
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75 * ====================================================
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76 */
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77
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78 /*
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79 Long double expansions contributed by
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80 Stephen L. Moshier <moshier@na-net.ornl.gov>
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81 */
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82
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83 /* __kernel_tanl( x, y, k )
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84 * kernel tan function on [-pi/4, pi/4], pi/4 ~ 0.7854
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85 * Input x is assumed to be bounded by ~pi/4 in magnitude.
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86 * Input y is the tail of x.
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87 * Input k indicates whether tan (if k=1) or
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88 * -1/tan (if k= -1) is returned.
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89 *
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90 * Algorithm
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91 * 1. Since tan(-x) = -tan(x), we need only to consider positive x.
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92 * 2. if x < 2^-57, return x with inexact if x!=0.
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93 * 3. tan(x) is approximated by a rational form x + x^3 / 3 + x^5 R(x^2)
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94 * on [0,0.67433].
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95 *
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96 * Note: tan(x+y) = tan(x) + tan'(x)*y
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97 * ~ tan(x) + (1+x*x)*y
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98 * Therefore, for better accuracy in computing tan(x+y), let
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99 * r = x^3 * R(x^2)
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100 * then
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101 * tan(x+y) = x + (x^3 / 3 + (x^2 *(r+y)+y))
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102 *
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103 * 4. For x in [0.67433,pi/4], let y = pi/4 - x, then
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104 * tan(x) = tan(pi/4-y) = (1-tan(y))/(1+tan(y))
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105 * = 1 - 2*(tan(y) - (tan(y)^2)/(1+tan(y)))
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106 */
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107
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108
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109 static const long double
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110 pio4hi = 7.8539816339744830961566084581987569936977E-1L,
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111 pio4lo = 2.1679525325309452561992610065108379921906E-35L,
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112
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113 /* tan x = x + x^3 / 3 + x^5 T(x^2)/U(x^2)
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114 0 <= x <= 0.6743316650390625
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115 Peak relative error 8.0e-36 */
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116 TH = 3.333333333333333333333333333333333333333E-1L,
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117 T0 = -1.813014711743583437742363284336855889393E7L,
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118 T1 = 1.320767960008972224312740075083259247618E6L,
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119 T2 = -2.626775478255838182468651821863299023956E4L,
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120 T3 = 1.764573356488504935415411383687150199315E2L,
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121 T4 = -3.333267763822178690794678978979803526092E-1L,
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122
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123 U0 = -1.359761033807687578306772463253710042010E8L,
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124 U1 = 6.494370630656893175666729313065113194784E7L,
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125 U2 = -4.180787672237927475505536849168729386782E6L,
b33b8603715c Transcendental functions for 'long double', from Paolo Bonzini.
Bruno Haible <bruno@clisp.org>
parents:
diff changeset
126 U3 = 8.031643765106170040139966622980914621521E4L,
b33b8603715c Transcendental functions for 'long double', from Paolo Bonzini.
Bruno Haible <bruno@clisp.org>
parents:
diff changeset
127 U4 = -5.323131271912475695157127875560667378597E2L;
b33b8603715c Transcendental functions for 'long double', from Paolo Bonzini.
Bruno Haible <bruno@clisp.org>
parents:
diff changeset
128 /* 1.000000000000000000000000000000000000000E0 */
b33b8603715c Transcendental functions for 'long double', from Paolo Bonzini.
Bruno Haible <bruno@clisp.org>
parents:
diff changeset
129
b33b8603715c Transcendental functions for 'long double', from Paolo Bonzini.
Bruno Haible <bruno@clisp.org>
parents:
diff changeset
130
12752
73d9dd27dc41 New modules acosl, asinl, atanl, cosl, expl, logl, sinl, sqrtl, tanl.
Bruno Haible <bruno@clisp.org>
parents: 12421
diff changeset
131 static long double
4239
b33b8603715c Transcendental functions for 'long double', from Paolo Bonzini.
Bruno Haible <bruno@clisp.org>
parents:
diff changeset
132 kernel_tanl (long double x, long double y, int iy)
b33b8603715c Transcendental functions for 'long double', from Paolo Bonzini.
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parents:
diff changeset
133 {
b33b8603715c Transcendental functions for 'long double', from Paolo Bonzini.
Bruno Haible <bruno@clisp.org>
parents:
diff changeset
134 long double z, r, v, w, s, u, u1;
9923
810b08d769f8 fix typos in mathl
Paolo Bonzini <bonzini@gnu.org>
parents: 8563
diff changeset
135 int invert = 0, sign;
4239
b33b8603715c Transcendental functions for 'long double', from Paolo Bonzini.
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parents:
diff changeset
136
8544
245a3653b197 Fix indentation.
Bruno Haible <bruno@clisp.org>
parents: 8186
diff changeset
137 sign = 1;
245a3653b197 Fix indentation.
Bruno Haible <bruno@clisp.org>
parents: 8186
diff changeset
138 if (x < 0)
245a3653b197 Fix indentation.
Bruno Haible <bruno@clisp.org>
parents: 8186
diff changeset
139 {
245a3653b197 Fix indentation.
Bruno Haible <bruno@clisp.org>
parents: 8186
diff changeset
140 x = -x;
245a3653b197 Fix indentation.
Bruno Haible <bruno@clisp.org>
parents: 8186
diff changeset
141 y = -y;
245a3653b197 Fix indentation.
Bruno Haible <bruno@clisp.org>
parents: 8186
diff changeset
142 sign = -1;
245a3653b197 Fix indentation.
Bruno Haible <bruno@clisp.org>
parents: 8186
diff changeset
143 }
4239
b33b8603715c Transcendental functions for 'long double', from Paolo Bonzini.
Bruno Haible <bruno@clisp.org>
parents:
diff changeset
144
b33b8603715c Transcendental functions for 'long double', from Paolo Bonzini.
Bruno Haible <bruno@clisp.org>
parents:
diff changeset
145 if (x < 0.000000000000000006938893903907228377647697925567626953125L) /* x < 2**-57 */
b33b8603715c Transcendental functions for 'long double', from Paolo Bonzini.
Bruno Haible <bruno@clisp.org>
parents:
diff changeset
146 {
b33b8603715c Transcendental functions for 'long double', from Paolo Bonzini.
Bruno Haible <bruno@clisp.org>
parents:
diff changeset
147 if ((int) x == 0)
12421
e8d2c6fc33ad Use spaces for indentation, not tabs.
Bruno Haible <bruno@clisp.org>
parents: 10667
diff changeset
148 { /* generate inexact */
e8d2c6fc33ad Use spaces for indentation, not tabs.
Bruno Haible <bruno@clisp.org>
parents: 10667
diff changeset
149 if (iy == -1 && x == 0.0)
e8d2c6fc33ad Use spaces for indentation, not tabs.
Bruno Haible <bruno@clisp.org>
parents: 10667
diff changeset
150 return 1.0L / fabs (x);
e8d2c6fc33ad Use spaces for indentation, not tabs.
Bruno Haible <bruno@clisp.org>
parents: 10667
diff changeset
151 else
e8d2c6fc33ad Use spaces for indentation, not tabs.
Bruno Haible <bruno@clisp.org>
parents: 10667
diff changeset
152 return (iy == 1) ? x : -1.0L / x;
e8d2c6fc33ad Use spaces for indentation, not tabs.
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parents: 10667
diff changeset
153 }
4239
b33b8603715c Transcendental functions for 'long double', from Paolo Bonzini.
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parents:
diff changeset
154 }
b33b8603715c Transcendental functions for 'long double', from Paolo Bonzini.
Bruno Haible <bruno@clisp.org>
parents:
diff changeset
155 if (x >= 0.6743316650390625) /* |x| >= 0.6743316650390625 */
b33b8603715c Transcendental functions for 'long double', from Paolo Bonzini.
Bruno Haible <bruno@clisp.org>
parents:
diff changeset
156 {
9923
810b08d769f8 fix typos in mathl
Paolo Bonzini <bonzini@gnu.org>
parents: 8563
diff changeset
157 invert = 1;
4239
b33b8603715c Transcendental functions for 'long double', from Paolo Bonzini.
Bruno Haible <bruno@clisp.org>
parents:
diff changeset
158
b33b8603715c Transcendental functions for 'long double', from Paolo Bonzini.
Bruno Haible <bruno@clisp.org>
parents:
diff changeset
159 z = pio4hi - x;
b33b8603715c Transcendental functions for 'long double', from Paolo Bonzini.
Bruno Haible <bruno@clisp.org>
parents:
diff changeset
160 w = pio4lo - y;
b33b8603715c Transcendental functions for 'long double', from Paolo Bonzini.
Bruno Haible <bruno@clisp.org>
parents:
diff changeset
161 x = z + w;
b33b8603715c Transcendental functions for 'long double', from Paolo Bonzini.
Bruno Haible <bruno@clisp.org>
parents:
diff changeset
162 y = 0.0;
b33b8603715c Transcendental functions for 'long double', from Paolo Bonzini.
Bruno Haible <bruno@clisp.org>
parents:
diff changeset
163 }
b33b8603715c Transcendental functions for 'long double', from Paolo Bonzini.
Bruno Haible <bruno@clisp.org>
parents:
diff changeset
164 z = x * x;
b33b8603715c Transcendental functions for 'long double', from Paolo Bonzini.
Bruno Haible <bruno@clisp.org>
parents:
diff changeset
165 r = T0 + z * (T1 + z * (T2 + z * (T3 + z * T4)));
b33b8603715c Transcendental functions for 'long double', from Paolo Bonzini.
Bruno Haible <bruno@clisp.org>
parents:
diff changeset
166 v = U0 + z * (U1 + z * (U2 + z * (U3 + z * (U4 + z))));
b33b8603715c Transcendental functions for 'long double', from Paolo Bonzini.
Bruno Haible <bruno@clisp.org>
parents:
diff changeset
167 r = r / v;
b33b8603715c Transcendental functions for 'long double', from Paolo Bonzini.
Bruno Haible <bruno@clisp.org>
parents:
diff changeset
168
b33b8603715c Transcendental functions for 'long double', from Paolo Bonzini.
Bruno Haible <bruno@clisp.org>
parents:
diff changeset
169 s = z * x;
b33b8603715c Transcendental functions for 'long double', from Paolo Bonzini.
Bruno Haible <bruno@clisp.org>
parents:
diff changeset
170 r = y + z * (s * r + y);
b33b8603715c Transcendental functions for 'long double', from Paolo Bonzini.
Bruno Haible <bruno@clisp.org>
parents:
diff changeset
171 r += TH * s;
b33b8603715c Transcendental functions for 'long double', from Paolo Bonzini.
Bruno Haible <bruno@clisp.org>
parents:
diff changeset
172 w = x + r;
9923
810b08d769f8 fix typos in mathl
Paolo Bonzini <bonzini@gnu.org>
parents: 8563
diff changeset
173 if (invert)
4239
b33b8603715c Transcendental functions for 'long double', from Paolo Bonzini.
Bruno Haible <bruno@clisp.org>
parents:
diff changeset
174 {
b33b8603715c Transcendental functions for 'long double', from Paolo Bonzini.
Bruno Haible <bruno@clisp.org>
parents:
diff changeset
175 v = (long double) iy;
b33b8603715c Transcendental functions for 'long double', from Paolo Bonzini.
Bruno Haible <bruno@clisp.org>
parents:
diff changeset
176 w = (v - 2.0 * (x - (w * w / (w + v) - r)));
b33b8603715c Transcendental functions for 'long double', from Paolo Bonzini.
Bruno Haible <bruno@clisp.org>
parents:
diff changeset
177 if (sign < 0)
12421
e8d2c6fc33ad Use spaces for indentation, not tabs.
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diff changeset
178 w = -w;
4239
b33b8603715c Transcendental functions for 'long double', from Paolo Bonzini.
Bruno Haible <bruno@clisp.org>
parents:
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179 return w;
b33b8603715c Transcendental functions for 'long double', from Paolo Bonzini.
Bruno Haible <bruno@clisp.org>
parents:
diff changeset
180 }
b33b8603715c Transcendental functions for 'long double', from Paolo Bonzini.
Bruno Haible <bruno@clisp.org>
parents:
diff changeset
181 if (iy == 1)
b33b8603715c Transcendental functions for 'long double', from Paolo Bonzini.
Bruno Haible <bruno@clisp.org>
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diff changeset
182 return w;
b33b8603715c Transcendental functions for 'long double', from Paolo Bonzini.
Bruno Haible <bruno@clisp.org>
parents:
diff changeset
183 else
12421
e8d2c6fc33ad Use spaces for indentation, not tabs.
Bruno Haible <bruno@clisp.org>
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diff changeset
184 { /* if allow error up to 2 ulp,
e8d2c6fc33ad Use spaces for indentation, not tabs.
Bruno Haible <bruno@clisp.org>
parents: 10667
diff changeset
185 simply return -1.0/(x+r) here */
4239
b33b8603715c Transcendental functions for 'long double', from Paolo Bonzini.
Bruno Haible <bruno@clisp.org>
parents:
diff changeset
186 /* compute -1.0/(x+r) accurately */
b33b8603715c Transcendental functions for 'long double', from Paolo Bonzini.
Bruno Haible <bruno@clisp.org>
parents:
diff changeset
187 u1 = (double) w;
b33b8603715c Transcendental functions for 'long double', from Paolo Bonzini.
Bruno Haible <bruno@clisp.org>
parents:
diff changeset
188 v = r - (u1 - x);
b33b8603715c Transcendental functions for 'long double', from Paolo Bonzini.
Bruno Haible <bruno@clisp.org>
parents:
diff changeset
189 z = -1.0 / w;
b33b8603715c Transcendental functions for 'long double', from Paolo Bonzini.
Bruno Haible <bruno@clisp.org>
parents:
diff changeset
190 u = (double) z;
b33b8603715c Transcendental functions for 'long double', from Paolo Bonzini.
Bruno Haible <bruno@clisp.org>
parents:
diff changeset
191 s = 1.0 + u * u1;
b33b8603715c Transcendental functions for 'long double', from Paolo Bonzini.
Bruno Haible <bruno@clisp.org>
parents:
diff changeset
192 return u + z * (s + u * v);
b33b8603715c Transcendental functions for 'long double', from Paolo Bonzini.
Bruno Haible <bruno@clisp.org>
parents:
diff changeset
193 }
b33b8603715c Transcendental functions for 'long double', from Paolo Bonzini.
Bruno Haible <bruno@clisp.org>
parents:
diff changeset
194 }
b33b8603715c Transcendental functions for 'long double', from Paolo Bonzini.
Bruno Haible <bruno@clisp.org>
parents:
diff changeset
195
b33b8603715c Transcendental functions for 'long double', from Paolo Bonzini.
Bruno Haible <bruno@clisp.org>
parents:
diff changeset
196 long double
b33b8603715c Transcendental functions for 'long double', from Paolo Bonzini.
Bruno Haible <bruno@clisp.org>
parents:
diff changeset
197 tanl (long double x)
b33b8603715c Transcendental functions for 'long double', from Paolo Bonzini.
Bruno Haible <bruno@clisp.org>
parents:
diff changeset
198 {
b33b8603715c Transcendental functions for 'long double', from Paolo Bonzini.
Bruno Haible <bruno@clisp.org>
parents:
diff changeset
199 long double y[2], z = 0.0L;
b33b8603715c Transcendental functions for 'long double', from Paolo Bonzini.
Bruno Haible <bruno@clisp.org>
parents:
diff changeset
200 int n;
b33b8603715c Transcendental functions for 'long double', from Paolo Bonzini.
Bruno Haible <bruno@clisp.org>
parents:
diff changeset
201
8563
c3d334708928 Better support of signalling NaNs.
Bruno Haible <bruno@clisp.org>
parents: 8544
diff changeset
202 /* tanl(NaN) is NaN */
c3d334708928 Better support of signalling NaNs.
Bruno Haible <bruno@clisp.org>
parents: 8544
diff changeset
203 if (isnanl (x))
c3d334708928 Better support of signalling NaNs.
Bruno Haible <bruno@clisp.org>
parents: 8544
diff changeset
204 return x;
c3d334708928 Better support of signalling NaNs.
Bruno Haible <bruno@clisp.org>
parents: 8544
diff changeset
205
4239
b33b8603715c Transcendental functions for 'long double', from Paolo Bonzini.
Bruno Haible <bruno@clisp.org>
parents:
diff changeset
206 /* |x| ~< pi/4 */
b33b8603715c Transcendental functions for 'long double', from Paolo Bonzini.
Bruno Haible <bruno@clisp.org>
parents:
diff changeset
207 if (x >= -0.7853981633974483096156608458198757210492 &&
b33b8603715c Transcendental functions for 'long double', from Paolo Bonzini.
Bruno Haible <bruno@clisp.org>
parents:
diff changeset
208 x <= 0.7853981633974483096156608458198757210492)
b33b8603715c Transcendental functions for 'long double', from Paolo Bonzini.
Bruno Haible <bruno@clisp.org>
parents:
diff changeset
209 return kernel_tanl (x, z, 1);
b33b8603715c Transcendental functions for 'long double', from Paolo Bonzini.
Bruno Haible <bruno@clisp.org>
parents:
diff changeset
210
8563
c3d334708928 Better support of signalling NaNs.
Bruno Haible <bruno@clisp.org>
parents: 8544
diff changeset
211 /* tanl(Inf) is NaN, tanl(0) is 0 */
c3d334708928 Better support of signalling NaNs.
Bruno Haible <bruno@clisp.org>
parents: 8544
diff changeset
212 else if (x + x == x)
12421
e8d2c6fc33ad Use spaces for indentation, not tabs.
Bruno Haible <bruno@clisp.org>
parents: 10667
diff changeset
213 return x - x; /* NaN */
4239
b33b8603715c Transcendental functions for 'long double', from Paolo Bonzini.
Bruno Haible <bruno@clisp.org>
parents:
diff changeset
214
b33b8603715c Transcendental functions for 'long double', from Paolo Bonzini.
Bruno Haible <bruno@clisp.org>
parents:
diff changeset
215 /* argument reduction needed */
b33b8603715c Transcendental functions for 'long double', from Paolo Bonzini.
Bruno Haible <bruno@clisp.org>
parents:
diff changeset
216 else
b33b8603715c Transcendental functions for 'long double', from Paolo Bonzini.
Bruno Haible <bruno@clisp.org>
parents:
diff changeset
217 {
b33b8603715c Transcendental functions for 'long double', from Paolo Bonzini.
Bruno Haible <bruno@clisp.org>
parents:
diff changeset
218 n = ieee754_rem_pio2l (x, y);
b33b8603715c Transcendental functions for 'long double', from Paolo Bonzini.
Bruno Haible <bruno@clisp.org>
parents:
diff changeset
219 /* 1 -- n even, -1 -- n odd */
b33b8603715c Transcendental functions for 'long double', from Paolo Bonzini.
Bruno Haible <bruno@clisp.org>
parents:
diff changeset
220 return kernel_tanl (y[0], y[1], 1 - ((n & 1) << 1));
b33b8603715c Transcendental functions for 'long double', from Paolo Bonzini.
Bruno Haible <bruno@clisp.org>
parents:
diff changeset
221 }
b33b8603715c Transcendental functions for 'long double', from Paolo Bonzini.
Bruno Haible <bruno@clisp.org>
parents:
diff changeset
222 }
b33b8603715c Transcendental functions for 'long double', from Paolo Bonzini.
Bruno Haible <bruno@clisp.org>
parents:
diff changeset
223
15941
83c276c24d2a tanl: Simplify for platforms where 'long double' == 'double'.
Bruno Haible <bruno@clisp.org>
parents: 13051
diff changeset
224 #endif
83c276c24d2a tanl: Simplify for platforms where 'long double' == 'double'.
Bruno Haible <bruno@clisp.org>
parents: 13051
diff changeset
225
4239
b33b8603715c Transcendental functions for 'long double', from Paolo Bonzini.
Bruno Haible <bruno@clisp.org>
parents:
diff changeset
226 #if 0
b33b8603715c Transcendental functions for 'long double', from Paolo Bonzini.
Bruno Haible <bruno@clisp.org>
parents:
diff changeset
227 int
4652
b09c3f1225b6 Remove K&R cruft.
Paul Eggert <eggert@cs.ucla.edu>
parents: 4239
diff changeset
228 main (void)
4239
b33b8603715c Transcendental functions for 'long double', from Paolo Bonzini.
Bruno Haible <bruno@clisp.org>
parents:
diff changeset
229 {
13051
094f6cfdb5c3 Minor formatting changes.
Bruno Haible <bruno@clisp.org>
parents: 12752
diff changeset
230 printf ("%.16Lg\n", tanl (0.7853981633974483096156608458198757210492));
094f6cfdb5c3 Minor formatting changes.
Bruno Haible <bruno@clisp.org>
parents: 12752
diff changeset
231 printf ("%.16Lg\n", tanl (-0.7853981633974483096156608458198757210492));
094f6cfdb5c3 Minor formatting changes.
Bruno Haible <bruno@clisp.org>
parents: 12752
diff changeset
232 printf ("%.16Lg\n", tanl (0.7853981633974483096156608458198757210492 *3));
094f6cfdb5c3 Minor formatting changes.
Bruno Haible <bruno@clisp.org>
parents: 12752
diff changeset
233 printf ("%.16Lg\n", tanl (-0.7853981633974483096156608458198757210492 *31));
094f6cfdb5c3 Minor formatting changes.
Bruno Haible <bruno@clisp.org>
parents: 12752
diff changeset
234 printf ("%.16Lg\n", tanl (0.7853981633974483096156608458198757210492 / 2));
094f6cfdb5c3 Minor formatting changes.
Bruno Haible <bruno@clisp.org>
parents: 12752
diff changeset
235 printf ("%.16Lg\n", tanl (0.7853981633974483096156608458198757210492 * 3/2));
094f6cfdb5c3 Minor formatting changes.
Bruno Haible <bruno@clisp.org>
parents: 12752
diff changeset
236 printf ("%.16Lg\n", tanl (0.7853981633974483096156608458198757210492 * 5/2));
4239
b33b8603715c Transcendental functions for 'long double', from Paolo Bonzini.
Bruno Haible <bruno@clisp.org>
parents:
diff changeset
237 }
b33b8603715c Transcendental functions for 'long double', from Paolo Bonzini.
Bruno Haible <bruno@clisp.org>
parents:
diff changeset
238 #endif