| #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 */ |
| |
| #ifdef _OSF_SOURCE |
| /* OSF1 5.1 doesn't make these available with XOPEN_SOURCE_EXTENDED defined */ |
| extern int finite(double); |
| extern double copysign(double, double); |
| #endif |
| |
| /* 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_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 |
| |
| #ifdef HAVE_GCC_ASM_FOR_X87 |
| PyAPI_FUNC(unsigned short) _Py_get_387controlword(void); |
| PyAPI_FUNC(void) _Py_set_387controlword(unsigned short); |
| #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 |
| * FIXME: PC/pyconfig.h defines Py_IS_INFINITY as (!_finite(X) && !_isnan(X)) |
| * so that above note isn't correct !!! |
| */ |
| #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 */ |
