晋太元中,武陵人捕鱼为业。缘溪行,忘路之远近。忽逢桃花林,夹岸数百步,中无杂树,芳草鲜美,落英缤纷。渔人甚异之,复前行,欲穷其林。 林尽水源,便得一山,山有小口,仿佛若有光。便舍船,从口入。初极狭,才通人。复行数十步,豁然开朗。土地平旷,屋舍俨然,有良田、美池、桑竹之属。阡陌交通,鸡犬相闻。其中往来种作,男女衣着,悉如外人。黄发垂髫,并怡然自乐。 见渔人,乃大惊,问所从来。具答之。便要还家,设酒杀鸡作食。村中闻有此人,咸来问讯。自云先世避秦时乱,率妻子邑人来此绝境,不复出焉,遂与外人间隔。问今是何世,乃不知有汉,无论魏晋。此人一一为具言所闻,皆叹惋。余人各复延至其家,皆出酒食。停数日,辞去。此中人语云:“不足为外人道也。”(间隔 一作:隔绝) 既出,得其船,便扶向路,处处志之。及郡下,诣太守,说如此。太守即遣人随其往,寻向所志,遂迷,不复得路。 南阳刘子骥,高尚士也,闻之,欣然规往。未果,寻病终。后遂无问津者。
| DIR:/opt/alt/python311/include/python3.11/ |
| Current File : //opt/alt/python311/include/python3.11/pymath.h |
// Symbols and macros to supply platform-independent interfaces to mathematical
// functions and constants.
#ifndef Py_PYMATH_H
#define Py_PYMATH_H
/* High precision definition of pi and e (Euler)
* The values are taken from libc6's math.h.
*/
#ifndef Py_MATH_PIl
#define Py_MATH_PIl 3.1415926535897932384626433832795029L
#endif
#ifndef Py_MATH_PI
#define Py_MATH_PI 3.14159265358979323846
#endif
#ifndef Py_MATH_El
#define Py_MATH_El 2.7182818284590452353602874713526625L
#endif
#ifndef Py_MATH_E
#define Py_MATH_E 2.7182818284590452354
#endif
/* Tau (2pi) to 40 digits, taken from tauday.com/tau-digits. */
#ifndef Py_MATH_TAU
#define Py_MATH_TAU 6.2831853071795864769252867665590057683943L
#endif
// Py_IS_NAN(X)
// Return 1 if float or double arg is a NaN, else 0.
#define Py_IS_NAN(X) isnan(X)
// Py_IS_INFINITY(X)
// Return 1 if float or double arg is an infinity, else 0.
#define Py_IS_INFINITY(X) isinf(X)
// Py_IS_FINITE(X)
// Return 1 if float or double arg is neither infinite nor NAN, else 0.
#define Py_IS_FINITE(X) isfinite(X)
/* HUGE_VAL is supposed to expand to a positive double infinity. Python
* uses Py_HUGE_VAL instead because some platforms are broken in this
* respect. We used to embed code in pyport.h to try to worm around that,
* but different platforms are broken in conflicting ways. If you're on
* a platform where HUGE_VAL is defined incorrectly, fiddle your Python
* config to #define Py_HUGE_VAL to something that works on your platform.
*/
#ifndef Py_HUGE_VAL
# define Py_HUGE_VAL HUGE_VAL
#endif
// Py_NAN: Value that evaluates to a quiet Not-a-Number (NaN).
#if !defined(Py_NAN)
# if _Py__has_builtin(__builtin_nan)
// Built-in implementation of the ISO C99 function nan(): quiet NaN.
# define Py_NAN (__builtin_nan(""))
#else
// Use C99 NAN constant: quiet Not-A-Number.
// NAN is a float, Py_NAN is a double: cast to double.
# define Py_NAN ((double)NAN)
# endif
#endif
#endif /* Py_PYMATH_H */
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