1
\input texinfo @c -*-texinfo-*-
4
@setfilename libquadmath.info
5
@settitle GCC libquadmath
9
Copyright @copyright{} 2010-2016 Free Software Foundation, Inc.
12
Permission is granted to copy, distribute and/or modify this document
13
under the terms of the GNU Free Documentation License, Version 1.2 or
14
any later version published by the Free Software Foundation; with no
15
Invariant Sections, with the Front-Cover Texts being ``A GNU Manual,''
16
and with the Back-Cover Texts as in (a) below. A copy of the
17
license is included in the section entitled ``GNU Free Documentation
20
(a) The FSF's Back-Cover Text is: ``You have the freedom to
21
copy and modify this GNU manual.
26
@dircategory GNU Libraries
28
* libquadmath: (libquadmath). GCC Quad-Precision Math Library
31
This manual documents the GCC Quad-Precision Math Library API.
33
Published by the Free Software Foundation
34
51 Franklin Street, Fifth Floor
35
Boston, MA 02110-1301 USA
41
@setchapternewpage odd
44
@title The GCC Quad-Precision Math Library
46
@vskip 0pt plus 1filll
47
@comment For the @value{version-GCC} Version*
49
Published by the Free Software Foundation @*
50
51 Franklin Street, Fifth Floor@*
51
Boston, MA 02110-1301, USA@*
65
This manual documents the usage of libquadmath, the GCC Quad-Precision
66
Math Library Application Programming Interface (API).
70
@comment When you add a new menu item, please keep the right hand
71
@comment aligned to the same column. Do not use tabs. This provides
72
@comment better formatting.
75
* Typedef and constants:: Defined data types and constants
76
* Math Library Routines:: The Libquadmath math runtime application
77
programming interface.
78
* I/O Library Routines:: The Libquadmath I/O runtime application
79
programming interface.
80
* GNU Free Documentation License::
81
How you can copy and share this manual.
82
* Reporting Bugs:: How to report bugs in GCC Libquadmath.
83
@c * Index:: Index of this documentation.
87
@c ---------------------------------------------------------------------
89
@c ---------------------------------------------------------------------
91
@node Typedef and constants
92
@chapter Typedef and constants
94
The following data type has been defined via @code{typedef}.
97
@item @code{__complex128}: @code{__float128}-based complex number
100
The following macros are defined, which give the numeric limits of the
101
@code{__float128} data type.
104
@item @code{FLT128_MAX}: largest finite number
105
@item @code{FLT128_MIN}: smallest positive number with full precision
106
@item @code{FLT128_EPSILON}: difference between 1 and the next larger
108
@item @code{FLT128_DENORM_MIN}: smallest positive denormalized number
109
@item @code{FLT128_MANT_DIG}: number of digits in the mantissa (bit precision)
110
@item @code{FLT128_MIN_EXP}: maximal negative exponent
111
@item @code{FLT128_MAX_EXP}: maximal positive exponent
112
@item @code{FLT128_DIG}: number of decimal digits in the mantissa
113
@item @code{FLT128_MIN_10_EXP}: maximal negative decimal exponent
114
@item @code{FLT128_MAX_10_EXP}: maximal positive decimal exponent
117
The following mathematical constants of type @code{__float128} are defined.
120
@item @code{M_Eq}: the constant e (Euler's number)
121
@item @code{M_LOG2Eq}: binary logarithm of 2
122
@item @code{M_LOG10Eq}: common, decimal logarithm of 2
123
@item @code{M_LN2q}: natural logarithm of 2
124
@item @code{M_LN10q}: natural logarithm of 10
125
@item @code{M_PIq}: pi
126
@item @code{M_PI_2q}: pi divided by two
127
@item @code{M_PI_4q}: pi divided by four
128
@item @code{M_1_PIq}: one over pi
129
@item @code{M_2_PIq}: one over two pi
130
@item @code{M_2_SQRTPIq}: two over square root of pi
131
@item @code{M_SQRT2q}: square root of 2
132
@item @code{M_SQRT1_2q}: one over square root of 2
136
@c ---------------------------------------------------------------------
138
@c ---------------------------------------------------------------------
140
@node Math Library Routines
141
@chapter Math Library Routines
143
The following mathematical functions are available:
146
@item @code{acosq}: arc cosine function
147
@item @code{acoshq}: inverse hyperbolic cosine function
148
@item @code{asinq}: arc sine function
149
@item @code{asinhq}: inverse hyperbolic sine function
150
@item @code{atanq}: arc tangent function
151
@item @code{atanhq}: inverse hyperbolic tangent function
152
@item @code{atan2q}: arc tangent function
153
@item @code{cbrtq}: cube root function
154
@item @code{ceilq}: ceiling value function
155
@item @code{copysignq}: copy sign of a number
156
@item @code{coshq}: hyperbolic cosine function
157
@item @code{cosq}: cosine function
158
@item @code{erfq}: error function
159
@item @code{erfcq}: complementary error function
160
@item @code{expq}: exponential function
161
@item @code{expm1q}: exponential minus 1 function
163
@item @code{fabsq}: absolute value function
164
@item @code{fdimq}: positive difference function
165
@item @code{finiteq}: check finiteness of value
166
@item @code{floorq}: floor value function
167
@item @code{fmaq}: fused multiply and add
168
@item @code{fmaxq}: determine maximum of two values
169
@item @code{fminq}: determine minimum of two values
170
@item @code{fmodq}: remainder value function
171
@item @code{frexpq}: extract mantissa and exponent
172
@item @code{hypotq}: Eucledian distance function
173
@item @code{ilogbq}: get exponent of the value
174
@item @code{isinfq}: check for infinity
175
@item @code{isnanq}: check for not a number
176
@item @code{j0q}: Bessel function of the first kind, first order
177
@item @code{j1q}: Bessel function of the first kind, second order
178
@item @code{jnq}: Bessel function of the first kind, @var{n}-th order
179
@item @code{ldexpq}: load exponent of the value
180
@item @code{lgammaq}: logarithmic gamma function
181
@item @code{llrintq}: round to nearest integer value
182
@item @code{llroundq}: round to nearest integer value away from zero
183
@item @code{logbq}: get exponent of the value
184
@item @code{logq}: natural logarithm function
185
@item @code{log10q}: base 10 logarithm function
186
@item @code{log1pq}: compute natural logarithm of the value plus one
187
@item @code{log2q}: base 2 logarithm function
189
@item @code{lrintq}: round to nearest integer value
190
@item @code{lroundq}: round to nearest integer value away from zero
191
@item @code{modfq}: decompose the floating-point number
192
@item @code{nanq}: return quiet NaN
193
@item @code{nearbyintq}: round to nearest integer
194
@item @code{nextafterq}: next representable floating-point number
195
@item @code{powq}: power function
196
@item @code{remainderq}: remainder function
197
@item @code{remquoq}: remainder and part of quotient
198
@item @code{rintq}: round-to-nearest integral value
199
@item @code{roundq}: round-to-nearest integral value, return @code{__float128}
200
@item @code{scalblnq}: compute exponent using @code{FLT_RADIX}
201
@item @code{scalbnq}: compute exponent using @code{FLT_RADIX}
202
@item @code{signbitq}: return sign bit
203
@item @code{sincosq}: calculate sine and cosine simultaneously
204
@item @code{sinhq}: hyperbolic sine function
205
@item @code{sinq}: sine function
206
@item @code{sqrtq}: square root function
207
@item @code{tanq}: tangent function
208
@item @code{tanhq}: hyperbolic tangent function
210
@item @code{tgammaq}: true gamma function
211
@item @code{truncq}: round to integer, towards zero
212
@item @code{y0q}: Bessel function of the second kind, first order
213
@item @code{y1q}: Bessel function of the second kind, second order
214
@item @code{ynq}: Bessel function of the second kind, @var{n}-th order
215
@item @code{cabsq} complex absolute value function
216
@item @code{cargq}: calculate the argument
217
@item @code{cimagq} imaginary part of complex number
218
@item @code{crealq}: real part of complex number
219
@item @code{cacoshq}: complex arc hyperbolic cosine function
220
@item @code{cacosq}: complex arc cosine function
221
@item @code{casinhq}: complex arc hyperbolic sine function
222
@item @code{casinq}: complex arc sine function
223
@item @code{catanhq}: complex arc hyperbolic tangent function
224
@item @code{catanq}: complex arc tangent function
225
@item @code{ccosq} complex cosine function:
226
@item @code{ccoshq}: complex hyperbolic cosine function
227
@item @code{cexpq}: complex exponential function
229
@item @code{cexpiq}: computes the exponential function of ``i'' times a
231
@item @code{clogq}: complex natural logarithm
232
@item @code{clog10q}: complex base 10 logarithm
233
@item @code{conjq}: complex conjugate function
234
@item @code{cpowq}: complex power function
235
@item @code{cprojq}: project into Riemann Sphere
236
@item @code{csinq}: complex sine function
237
@item @code{csinhq}: complex hyperbolic sine function
238
@item @code{csqrtq}: complex square root
239
@item @code{ctanq}: complex tangent function
240
@item @code{ctanhq}: complex hyperbolic tangent function
244
@c ---------------------------------------------------------------------
246
@c ---------------------------------------------------------------------
248
@node I/O Library Routines
249
@chapter I/O Library Routines
252
* @code{strtoflt128}: strtoflt128, Convert from string
253
* @code{quadmath_snprintf}: quadmath_snprintf, Convert to string
258
@section @code{strtoflt128} --- Convert from string
260
The function @code{strtoflt128} converts a string into a
261
@code{__float128} number.
265
@code{__float128 strtoflt128 (const char *s, char **sp)}
267
@item @emph{Arguments}:
268
@multitable @columnfractions .15 .70
269
@item @var{s} @tab input string
270
@item @var{sp} @tab the address of the next character in the string
273
The argument @var{sp} contains, if not @code{NULL}, the address of the
274
next character following the parts of the string, which have been read.
278
#include <quadmath.h>
284
r = strtoflt128 ("1.2345678", NULL);
292
@node quadmath_snprintf
293
@section @code{quadmath_snprintf} --- Convert to string
295
The function @code{quadmath_snprintf} converts a @code{__float128} floating-point
296
number into a string. It is a specialized alternative to @code{snprintf}, where
297
the format string is restricted to a single conversion specifier with @code{Q}
298
modifier and conversion specifier @code{e}, @code{E}, @code{f}, @code{F}, @code{g},
299
@code{G}, @code{a} or @code{A}, with no extra characters before or after the
300
conversion specifier. The @code{%m$} or @code{*m$} style must not be used in
305
@code{int quadmath_snprintf (char *s, size_t size, const char *format, ...)}
307
@item @emph{Arguments}:
308
@multitable @columnfractions .15 .70
309
@item @var{s} @tab output string
310
@item @var{size} @tab byte size of the string, including tailing NUL
311
@item @var{format} @tab conversion specifier string
315
On some targets when supported by the C library hooks are installed
316
for @code{printf} family of functions, so that @code{printf ("%Qe", 1.2Q);}
321
#include <quadmath.h>
334
int n = quadmath_snprintf (buf, sizeof buf, "%+-#*.20Qe", width, r);
335
if ((size_t) n < sizeof buf)
336
printf ("%s\n", buf);
337
/* Prints: +1.41421356237309504880e+00 */
338
quadmath_snprintf (buf, sizeof buf, "%Qa", r);
339
if ((size_t) n < sizeof buf)
340
printf ("%s\n", buf);
341
/* Prints: 0x1.6a09e667f3bcc908b2fb1366ea96p+0 */
342
n = quadmath_snprintf (NULL, 0, "%+-#46.*Qe", prec, r);
345
char *str = malloc (n + 1);
348
quadmath_snprintf (str, n + 1, "%+-#46.*Qe", prec, r);
349
printf ("%s\n", str);
350
/* Prints: +1.41421356237309504880e+00 */
361
@c ---------------------------------------------------------------------
362
@c GNU Free Documentation License
363
@c ---------------------------------------------------------------------
367
@c ---------------------------------------------------------------------
369
@c ---------------------------------------------------------------------
372
@include libquadmath-vers.texi
375
@chapter Reporting Bugs
377
Bugs in the GCC Quad-Precision Math Library implementation should be
378
reported via @value{BUGURL}.
381
@c ---------------------------------------------------------------------
383
@c ---------------------------------------------------------------------