mirror of
https://github.com/python/cpython.git
synced 2024-12-15 21:04:00 +08:00
191 lines
6.3 KiB
C
191 lines
6.3 KiB
C
#ifndef Py_PYMATH_H
|
|
#define Py_PYMATH_H
|
|
|
|
#include "pyconfig.h" /* include for defines */
|
|
|
|
/**************************************************************************
|
|
Symbols and macros to supply platform-independent interfaces to mathematical
|
|
functions and constants
|
|
**************************************************************************/
|
|
|
|
/* Python provides implementations for copysign, round and hypot in
|
|
* Python/pymath.c just in case your math library doesn't provide the
|
|
* functions.
|
|
*
|
|
*Note: PC/pyconfig.h defines copysign as _copysign
|
|
*/
|
|
#ifndef HAVE_COPYSIGN
|
|
extern double copysign(double, double);
|
|
#endif
|
|
|
|
#ifndef HAVE_ROUND
|
|
extern double round(double);
|
|
#endif
|
|
|
|
#ifndef HAVE_HYPOT
|
|
extern double hypot(double, double);
|
|
#endif
|
|
|
|
/* extra declarations */
|
|
#ifndef _MSC_VER
|
|
#ifndef __STDC__
|
|
extern double fmod (double, double);
|
|
extern double frexp (double, int *);
|
|
extern double ldexp (double, int);
|
|
extern double modf (double, double *);
|
|
extern double pow(double, double);
|
|
#endif /* __STDC__ */
|
|
#endif /* _MSC_VER */
|
|
|
|
/* High precision defintion 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
|
|
|
|
/* On x86, Py_FORCE_DOUBLE forces a floating-point number out of an x87 FPU
|
|
register and into a 64-bit memory location, rounding from extended
|
|
precision to double precision in the process. On other platforms it does
|
|
nothing. */
|
|
|
|
/* we take double rounding as evidence of x87 usage */
|
|
#ifndef Py_LIMITED_API
|
|
#ifndef Py_FORCE_DOUBLE
|
|
# ifdef X87_DOUBLE_ROUNDING
|
|
PyAPI_FUNC(double) _Py_force_double(double);
|
|
# define Py_FORCE_DOUBLE(X) (_Py_force_double(X))
|
|
# else
|
|
# define Py_FORCE_DOUBLE(X) (X)
|
|
# endif
|
|
#endif
|
|
#endif
|
|
|
|
#ifndef Py_LIMITED_API
|
|
#ifdef HAVE_GCC_ASM_FOR_X87
|
|
PyAPI_FUNC(unsigned short) _Py_get_387controlword(void);
|
|
PyAPI_FUNC(void) _Py_set_387controlword(unsigned short);
|
|
#endif
|
|
#endif
|
|
|
|
/* Py_IS_NAN(X)
|
|
* Return 1 if float or double arg is a NaN, else 0.
|
|
* Caution:
|
|
* X is evaluated more than once.
|
|
* This may not work on all platforms. Each platform has *some*
|
|
* way to spell this, though -- override in pyconfig.h if you have
|
|
* a platform where it doesn't work.
|
|
* Note: PC/pyconfig.h defines Py_IS_NAN as _isnan
|
|
*/
|
|
#ifndef Py_IS_NAN
|
|
#if defined HAVE_DECL_ISNAN && HAVE_DECL_ISNAN == 1
|
|
#define Py_IS_NAN(X) isnan(X)
|
|
#else
|
|
#define Py_IS_NAN(X) ((X) != (X))
|
|
#endif
|
|
#endif
|
|
|
|
/* Py_IS_INFINITY(X)
|
|
* Return 1 if float or double arg is an infinity, else 0.
|
|
* Caution:
|
|
* X is evaluated more than once.
|
|
* This implementation may set the underflow flag if |X| is very small;
|
|
* it really can't be implemented correctly (& easily) before C99.
|
|
* Override in pyconfig.h if you have a better spelling on your platform.
|
|
* Py_FORCE_DOUBLE is used to avoid getting false negatives from a
|
|
* non-infinite value v sitting in an 80-bit x87 register such that
|
|
* v becomes infinite when spilled from the register to 64-bit memory.
|
|
* Note: PC/pyconfig.h defines Py_IS_INFINITY as _isinf
|
|
*/
|
|
#ifndef Py_IS_INFINITY
|
|
# if defined HAVE_DECL_ISINF && HAVE_DECL_ISINF == 1
|
|
# define Py_IS_INFINITY(X) isinf(X)
|
|
# else
|
|
# define Py_IS_INFINITY(X) ((X) && \
|
|
(Py_FORCE_DOUBLE(X)*0.5 == Py_FORCE_DOUBLE(X)))
|
|
# endif
|
|
#endif
|
|
|
|
/* Py_IS_FINITE(X)
|
|
* Return 1 if float or double arg is neither infinite nor NAN, else 0.
|
|
* Some compilers (e.g. VisualStudio) have intrisics for this, so a special
|
|
* macro for this particular test is useful
|
|
* Note: PC/pyconfig.h defines Py_IS_FINITE as _finite
|
|
*/
|
|
#ifndef Py_IS_FINITE
|
|
#if defined HAVE_DECL_ISFINITE && HAVE_DECL_ISFINITE == 1
|
|
#define Py_IS_FINITE(X) isfinite(X)
|
|
#elif defined HAVE_FINITE
|
|
#define Py_IS_FINITE(X) finite(X)
|
|
#else
|
|
#define Py_IS_FINITE(X) (!Py_IS_INFINITY(X) && !Py_IS_NAN(X))
|
|
#endif
|
|
#endif
|
|
|
|
/* 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
|
|
* A value that evaluates to a NaN. On IEEE 754 platforms INF*0 or
|
|
* INF/INF works. Define Py_NO_NAN in pyconfig.h if your platform
|
|
* doesn't support NaNs.
|
|
*/
|
|
#if !defined(Py_NAN) && !defined(Py_NO_NAN)
|
|
#define Py_NAN (Py_HUGE_VAL * 0.)
|
|
#endif
|
|
|
|
/* Py_OVERFLOWED(X)
|
|
* Return 1 iff a libm function overflowed. Set errno to 0 before calling
|
|
* a libm function, and invoke this macro after, passing the function
|
|
* result.
|
|
* Caution:
|
|
* This isn't reliable. C99 no longer requires libm to set errno under
|
|
* any exceptional condition, but does require +- HUGE_VAL return
|
|
* values on overflow. A 754 box *probably* maps HUGE_VAL to a
|
|
* double infinity, and we're cool if that's so, unless the input
|
|
* was an infinity and an infinity is the expected result. A C89
|
|
* system sets errno to ERANGE, so we check for that too. We're
|
|
* out of luck if a C99 754 box doesn't map HUGE_VAL to +Inf, or
|
|
* if the returned result is a NaN, or if a C89 box returns HUGE_VAL
|
|
* in non-overflow cases.
|
|
* X is evaluated more than once.
|
|
* Some platforms have better way to spell this, so expect some #ifdef'ery.
|
|
*
|
|
* OpenBSD uses 'isinf()' because a compiler bug on that platform causes
|
|
* the longer macro version to be mis-compiled. This isn't optimal, and
|
|
* should be removed once a newer compiler is available on that platform.
|
|
* The system that had the failure was running OpenBSD 3.2 on Intel, with
|
|
* gcc 2.95.3.
|
|
*
|
|
* According to Tim's checkin, the FreeBSD systems use isinf() to work
|
|
* around a FPE bug on that platform.
|
|
*/
|
|
#if defined(__FreeBSD__) || defined(__OpenBSD__)
|
|
#define Py_OVERFLOWED(X) isinf(X)
|
|
#else
|
|
#define Py_OVERFLOWED(X) ((X) != 0.0 && (errno == ERANGE || \
|
|
(X) == Py_HUGE_VAL || \
|
|
(X) == -Py_HUGE_VAL))
|
|
#endif
|
|
|
|
#endif /* Py_PYMATH_H */
|