math/math.h

   1 /* Declarations for math functions.
   2    Copyright (C) 1991, 92, 93, 95, 96, 97 Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   4
   5    The GNU C Library is free software; you can redistribute it and/or
   6    modify it under the terms of the GNU Library General Public License as
   7    published by the Free Software Foundation; either version 2 of the
   8    License, or (at your option) any later version.
   9
  10    The GNU C Library is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13    Library General Public License for more details.
  14
  15    You should have received a copy of the GNU Library General Public
  16    License along with the GNU C Library; see the file COPYING.LIB.  If not,
  17    write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  18    Boston, MA 02111-1307, USA.  */
  19
  20 /*
  21  *      ISO C Standard: 4.5 MATHEMATICS <math.h>
  22  */
  23
  24 #ifndef _MATH_H
  25
  26 #define _MATH_H 1
  27 #include <features.h>
  28
  29 __BEGIN_DECLS
  30
  31 /* Get machine-dependent HUGE_VAL value (returned on overflow).
  32    On all IEEE754 machines, this is +Infinity.  */
  33 #include <huge_val.h>
  34
  35 /* Get machine-dependent NAN value (returned for some domain errors).  */
  36 #ifdef   __USE_GNU
  37 #include <nan.h>
  38 #endif
  39
  40
  41 /* The file <mathcalls.h> contains the prototypes for all the actual
  42    math functions.  These macros are used for those prototypes, so
  43    we can easily declare each function as both `name' and `__name',
  44    and can declare the float versions `namef' and `__namef'.  */
  45
  46 #define __MATHCALL(function,suffix, args)       \
  47   __MATHDECL (_Mdouble_,function,suffix, args)
  48 #define __MATHDECL(type, function,suffix, args) \
  49   __MATHDECL_1(type, function,suffix, args); \
  50   __MATHDECL_1(type, __CONCAT(__,function),suffix, args)
  51 #define __MATHDECL_1(type, function,suffix, args) \
  52   extern type __MATH_PRECNAME(function,suffix) args
  53
  54 #define _Mdouble_               double
  55 #define __MATH_PRECNAME(name,r) __CONCAT(name,r)
  56 #include <mathcalls.h>
  57 #undef  _Mdouble_
  58 #undef  __MATH_PRECNAME
  59
  60 #if defined __USE_MISC || defined __USE_ISOC9X
  61
  62
  63 /* Include the file of declarations again, this time using `float'
  64    instead of `double' and appending f to each function name.  */
  65
  66 #ifndef _Mfloat_
  67 #define _Mfloat_                float
  68 #endif
  69 #define _Mdouble_               _Mfloat_
  70 #ifdef __STDC__
  71 #define __MATH_PRECNAME(name,r) name##f##r
  72 #else
  73 #define __MATH_PRECNAME(name,r) name/**/f/**/r
  74 #endif
  75 #include <mathcalls.h>
  76 #undef  _Mdouble_
  77 #undef  __MATH_PRECNAME
  78
  79 #if __STDC__ - 0 || __GNUC__ - 0
  80 /* Include the file of declarations again, this time using `long double'
  81    instead of `double' and appending l to each function name.  */
  82
  83 #ifndef _Mlong_double_
  84 #define _Mlong_double_          long double
  85 #endif
  86 #define _Mdouble_               _Mlong_double_
  87 #ifdef __STDC__
  88 #define __MATH_PRECNAME(name,r) name##l##r
  89 #else
  90 #define __MATH_PRECNAME(name,r) name/**/l/**/r
  91 #endif
  92 #include <mathcalls.h>
  93 #undef  _Mdouble_
  94 #undef  __MATH_PRECNAME
  95
  96 #endif /* __STDC__ || __GNUC__ */
  97
  98 #endif  /* Use misc or ISO C 9X.  */
  99 #undef  __MATHDECL_1
 100 #undef  __MATHDECL
 101 #undef  __MATHCALL
 102
 103
 104 #if defined __USE_MISC || defined __USE_XOPEN || defined __USE_ISOC9X
 105 /* This variable is used by `gamma' and `lgamma'.  */
 106 extern int signgam;
 107 #endif
 108
 109
 110 /* ISO C 9X defines some generic macros which work on any data type.  */
 111 #if __USE_ISOC9X
 112
 113 /* All floating-point numbers can be put in one of these categories.  */
 114 enum
 115   {
 116     FP_NAN,
 117 #define FP_NAN FP_NAN
 118     FP_INFINITE,
 119 #define FP_INFINITE FP_INFINITE
 120     FP_ZERO,
 121 #define FP_ZERO FP_ZERO
 122     FP_SUBNORMAL,
 123 #define FP_SUBNORMAL FP_SUBNORMAL
 124     FP_NORMAL
 125 #define FP_NORMAL FP_NORMAL
 126   };
 127
 128 /* Return number of classification appropriate for X.  */
 129 #define fpclassify(x) \
 130      (sizeof (x) == sizeof (float) ?                                          \
 131         __finitef (x)                                                         \
 132       : sizeof (x) == sizeof (double) ?                                       \
 133         __finite (x) : __finitel (x))
 134
 135 /* Return nonzero value if sign of X is negative.  */
 136 #define signbit(x) \
 137      (sizeof (x) == sizeof (float) ?                                          \
 138         __signbitf (x)                                                        \
 139       : sizeof (x) == sizeof (double) ?                                       \
 140         __signbit (x) : __signbitl (x))
 141
 142 /* Return nonzero value if X is not +-Inf or NaN.  */
 143 #define isfinite(x) (fpclassify (x) >= FP_ZERO)
 144
 145 /* Return nonzero value if X is neither zero, subnormal, Inf, nor NaN.  */
 146 #define isnormal(x) (fpclassify (x) == FP_NORMAL)
 147
 148 /* Return nonzero value if X is a NaN.  We could use `fpclassify' but
 149    we already have this functions `__isnan' and it is faster.  */
 150 #define isnan(x) \
 151      (sizeof (x) == sizeof (float) ?                                          \
 152         __isnanf (x)                                                          \
 153       : sizeof (x) == sizeof (double) ?                                       \
 154         __isnan (x) : __isnanl (x))
 155
 156
 157 /* Conversion functions.  */
 158
 159 /* Round X to nearest integral value according to current rounding
 160    direction.  */
 161 extern long int rinttol __P ((double __x));
 162 extern long long int rinttoll __P ((double __x));
 163
 164 /* Round X to nearest integral value, rounding halfway cases away from
 165    zero.  */
 166 extern long int roundtol __P ((double __x));
 167 extern long long int roundtoll __P ((double __x));
 168
 169
 170 /* Comparison macros.  */
 171
 172 /* Return nonzero value if X is greater than Y.  */
 173 #define isgreater(x, y) (!isunordered ((x), (y)) && (x) > (y))
 174
 175 /* Return nonzero value if X is greater than or equal to Y.  */
 176 #define isgreaterequal(x, y) (!isunordered ((x), (y)) && (x) >= (y))
 177
 178 /* Return nonzero value if X is less than Y.  */
 179 #define isless(x, y) (!isunordered ((x), (y)) && (x) < (y))
 180
 181 /* Return nonzero value if X is less than or equal to Y.  */
 182 #define islessequal(x, y) (!isunordered ((x), (y)) && (x) <= (y))
 183
 184 /* Return nonzero value if either X is less than Y or Y is less than X.  */
 185 #define islessgreater(x, y) \
 186      (!isunordered ((x), (y)) && ((x) < (y) || (y) < (x)))
 187
 188 /* Return nonzero value if arguments are unordered.  */
 189 #define isunordered(x, y) \
 190      (fpclassify (x) == FP_NAN || fpclassify (y) == FP_NAN)
 191
 192 #endif /* Use ISO C 9X.  */
 193
 194 #ifdef  __USE_MISC
 195 /* Support for various different standard error handling behaviors.  */
 196
 197 typedef enum { _IEEE_ = -1, _SVID_, _XOPEN_, _POSIX_ } _LIB_VERSION_TYPE;
 198
 199 /* This variable can be changed at run-time to any of the values above to
 200    affect floating point error handling behavior (it may also be necessary
 201    to change the hardware FPU exception settings).  */
 202 extern _LIB_VERSION_TYPE _LIB_VERSION;
 203 #endif
 204
 205
 206 #ifdef __USE_SVID
 207 /* In SVID error handling, `matherr' is called with this description
 208    of the exceptional condition.
 209
 210    We have a problem when using C++ since `exception' is reserved in
 211    C++.  */
 212 #ifdef __cplusplus
 213 struct __exception
 214 #else
 215 struct exception
 216 #endif
 217   {
 218     int type;
 219     char *name;
 220     double arg1;
 221     double arg2;
 222     double retval;
 223   };
 224
 225 #ifdef __cplusplus
 226 extern int __matherr __P ((struct __exception *));
 227 extern int matherr __P ((struct __exception *));
 228 #else
 229 extern int __matherr __P ((struct exception *));
 230 extern int matherr __P ((struct exception *));
 231 #endif
 232
 233 #define X_TLOSS         1.41484755040568800000e+16
 234
 235 /* Types of exceptions in the `type' field.  */
 236 #define DOMAIN          1
 237 #define SING            2
 238 #define OVERFLOW        3
 239 #define UNDERFLOW       4
 240 #define TLOSS           5
 241 #define PLOSS           6
 242
 243 /* SVID mode specifies returning this large value instead of infinity.  */
 244 #define HUGE            FLT_MAX
 245 #include <float.h>              /* Defines FLT_MAX.  */
 246
 247 #else   /* !SVID */
 248
 249 #ifdef __USE_XOPEN
 250 /* X/Open wants another strange constant.  */
 251 #define MAXFLOAT        FLT_MAX
 252 #include <float.h>
 253 #endif
 254
 255 #endif  /* SVID */
 256
 257
 258 #ifdef __USE_BSD
 259
 260 /* Some useful constants.  */
 261 #define M_E             _Mldbl(2.7182818284590452354)   /* e */
 262 #define M_LOG2E         _Mldbl(1.4426950408889634074)   /* log 2e */
 263 #define M_LOG10E        _Mldbl(0.43429448190325182765)  /* log 10e */
 264 #define M_LN2           _Mldbl(0.69314718055994530942)  /* log e2 */
 265 #define M_LN10          _Mldbl(2.30258509299404568402)  /* log e10 */
 266 #define M_PI            _Mldbl(3.14159265358979323846)  /* pi */
 267 #define M_PI_2          _Mldbl(1.57079632679489661923)  /* pi/2 */
 268 #define M_PI_4          _Mldbl(0.78539816339744830962)  /* pi/4 */
 269 #define M_1_PI          _Mldbl(0.31830988618379067154)  /* 1/pi */
 270 #define M_2_PI          _Mldbl(0.63661977236758134308)  /* 2/pi */
 271 #define M_2_SQRTPI      _Mldbl(1.12837916709551257390)  /* 2/sqrt(pi) */
 272 #define M_SQRT2         _Mldbl(1.41421356237309504880)  /* sqrt(2) */
 273 #define M_SQRT1_2       _Mldbl(0.70710678118654752440)  /* 1/sqrt(2) */
 274
 275 /* Our constants might specify more precision than `double' can represent.
 276    Use `long double' constants in standard and GNU C, where they are
 277    supported and the cast to `double'.  */
 278 #if __STDC__ - 0 || __GNUC__ - 0
 279 #define _Mldbl(x) x##L
 280 #else   /* Traditional C.  */
 281 #define _Mldbl(x) x
 282 #endif  /* Standard or GNU C.  */
 283
 284 #endif
 285
 286
 287 /* Get machine-dependent inline versions (if there are any).  */
 288 #if (!defined __NO_MATH_INLINES && defined __OPTIMIZE__) \
 289     || defined __LIBC_M81_MATH_INLINES
 290 #include <__math.h>
 291 #endif
 292
 293
 294 __END_DECLS
 295
 296
 297 #endif /* math.h  */