jpayne@69: #ifndef Py_PYMATH_H
jpayne@69: #define Py_PYMATH_H
jpayne@69: 
jpayne@69: #include "pyconfig.h" /* include for defines */
jpayne@69: 
jpayne@69: /**************************************************************************
jpayne@69: Symbols and macros to supply platform-independent interfaces to mathematical
jpayne@69: functions and constants
jpayne@69: **************************************************************************/
jpayne@69: 
jpayne@69: /* Python provides implementations for copysign, round and hypot in
jpayne@69:  * Python/pymath.c just in case your math library doesn't provide the
jpayne@69:  * functions.
jpayne@69:  *
jpayne@69:  *Note: PC/pyconfig.h defines copysign as _copysign
jpayne@69:  */
jpayne@69: #ifndef HAVE_COPYSIGN
jpayne@69: extern double copysign(double, double);
jpayne@69: #endif
jpayne@69: 
jpayne@69: #ifndef HAVE_ROUND
jpayne@69: extern double round(double);
jpayne@69: #endif
jpayne@69: 
jpayne@69: #ifndef HAVE_HYPOT
jpayne@69: extern double hypot(double, double);
jpayne@69: #endif
jpayne@69: 
jpayne@69: /* extra declarations */
jpayne@69: #ifndef _MSC_VER
jpayne@69: #ifndef __STDC__
jpayne@69: extern double fmod (double, double);
jpayne@69: extern double frexp (double, int *);
jpayne@69: extern double ldexp (double, int);
jpayne@69: extern double modf (double, double *);
jpayne@69: extern double pow(double, double);
jpayne@69: #endif /* __STDC__ */
jpayne@69: #endif /* _MSC_VER */
jpayne@69: 
jpayne@69: /* High precision definition of pi and e (Euler)
jpayne@69:  * The values are taken from libc6's math.h.
jpayne@69:  */
jpayne@69: #ifndef Py_MATH_PIl
jpayne@69: #define Py_MATH_PIl 3.1415926535897932384626433832795029L
jpayne@69: #endif
jpayne@69: #ifndef Py_MATH_PI
jpayne@69: #define Py_MATH_PI 3.14159265358979323846
jpayne@69: #endif
jpayne@69: 
jpayne@69: #ifndef Py_MATH_El
jpayne@69: #define Py_MATH_El 2.7182818284590452353602874713526625L
jpayne@69: #endif
jpayne@69: 
jpayne@69: #ifndef Py_MATH_E
jpayne@69: #define Py_MATH_E 2.7182818284590452354
jpayne@69: #endif
jpayne@69: 
jpayne@69: /* Tau (2pi) to 40 digits, taken from tauday.com/tau-digits. */
jpayne@69: #ifndef Py_MATH_TAU
jpayne@69: #define Py_MATH_TAU 6.2831853071795864769252867665590057683943L
jpayne@69: #endif
jpayne@69: 
jpayne@69: 
jpayne@69: /* On x86, Py_FORCE_DOUBLE forces a floating-point number out of an x87 FPU
jpayne@69:    register and into a 64-bit memory location, rounding from extended
jpayne@69:    precision to double precision in the process.  On other platforms it does
jpayne@69:    nothing. */
jpayne@69: 
jpayne@69: /* we take double rounding as evidence of x87 usage */
jpayne@69: #ifndef Py_LIMITED_API
jpayne@69: #ifndef Py_FORCE_DOUBLE
jpayne@69: #  ifdef X87_DOUBLE_ROUNDING
jpayne@69: PyAPI_FUNC(double) _Py_force_double(double);
jpayne@69: #    define Py_FORCE_DOUBLE(X) (_Py_force_double(X))
jpayne@69: #  else
jpayne@69: #    define Py_FORCE_DOUBLE(X) (X)
jpayne@69: #  endif
jpayne@69: #endif
jpayne@69: #endif
jpayne@69: 
jpayne@69: #ifndef Py_LIMITED_API
jpayne@69: #ifdef HAVE_GCC_ASM_FOR_X87
jpayne@69: PyAPI_FUNC(unsigned short) _Py_get_387controlword(void);
jpayne@69: PyAPI_FUNC(void) _Py_set_387controlword(unsigned short);
jpayne@69: #endif
jpayne@69: #endif
jpayne@69: 
jpayne@69: /* Py_IS_NAN(X)
jpayne@69:  * Return 1 if float or double arg is a NaN, else 0.
jpayne@69:  * Caution:
jpayne@69:  *     X is evaluated more than once.
jpayne@69:  *     This may not work on all platforms.  Each platform has *some*
jpayne@69:  *     way to spell this, though -- override in pyconfig.h if you have
jpayne@69:  *     a platform where it doesn't work.
jpayne@69:  * Note: PC/pyconfig.h defines Py_IS_NAN as _isnan
jpayne@69:  */
jpayne@69: #ifndef Py_IS_NAN
jpayne@69: #if defined HAVE_DECL_ISNAN && HAVE_DECL_ISNAN == 1
jpayne@69: #define Py_IS_NAN(X) isnan(X)
jpayne@69: #else
jpayne@69: #define Py_IS_NAN(X) ((X) != (X))
jpayne@69: #endif
jpayne@69: #endif
jpayne@69: 
jpayne@69: /* Py_IS_INFINITY(X)
jpayne@69:  * Return 1 if float or double arg is an infinity, else 0.
jpayne@69:  * Caution:
jpayne@69:  *    X is evaluated more than once.
jpayne@69:  *    This implementation may set the underflow flag if |X| is very small;
jpayne@69:  *    it really can't be implemented correctly (& easily) before C99.
jpayne@69:  *    Override in pyconfig.h if you have a better spelling on your platform.
jpayne@69:  *  Py_FORCE_DOUBLE is used to avoid getting false negatives from a
jpayne@69:  *    non-infinite value v sitting in an 80-bit x87 register such that
jpayne@69:  *    v becomes infinite when spilled from the register to 64-bit memory.
jpayne@69:  * Note: PC/pyconfig.h defines Py_IS_INFINITY as _isinf
jpayne@69:  */
jpayne@69: #ifndef Py_IS_INFINITY
jpayne@69: #  if defined HAVE_DECL_ISINF && HAVE_DECL_ISINF == 1
jpayne@69: #    define Py_IS_INFINITY(X) isinf(X)
jpayne@69: #  else
jpayne@69: #    define Py_IS_INFINITY(X) ((X) &&                                   \
jpayne@69:                                (Py_FORCE_DOUBLE(X)*0.5 == Py_FORCE_DOUBLE(X)))
jpayne@69: #  endif
jpayne@69: #endif
jpayne@69: 
jpayne@69: /* Py_IS_FINITE(X)
jpayne@69:  * Return 1 if float or double arg is neither infinite nor NAN, else 0.
jpayne@69:  * Some compilers (e.g. VisualStudio) have intrisics for this, so a special
jpayne@69:  * macro for this particular test is useful
jpayne@69:  * Note: PC/pyconfig.h defines Py_IS_FINITE as _finite
jpayne@69:  */
jpayne@69: #ifndef Py_IS_FINITE
jpayne@69: #if defined HAVE_DECL_ISFINITE && HAVE_DECL_ISFINITE == 1
jpayne@69: #define Py_IS_FINITE(X) isfinite(X)
jpayne@69: #elif defined HAVE_FINITE
jpayne@69: #define Py_IS_FINITE(X) finite(X)
jpayne@69: #else
jpayne@69: #define Py_IS_FINITE(X) (!Py_IS_INFINITY(X) && !Py_IS_NAN(X))
jpayne@69: #endif
jpayne@69: #endif
jpayne@69: 
jpayne@69: /* HUGE_VAL is supposed to expand to a positive double infinity.  Python
jpayne@69:  * uses Py_HUGE_VAL instead because some platforms are broken in this
jpayne@69:  * respect.  We used to embed code in pyport.h to try to worm around that,
jpayne@69:  * but different platforms are broken in conflicting ways.  If you're on
jpayne@69:  * a platform where HUGE_VAL is defined incorrectly, fiddle your Python
jpayne@69:  * config to #define Py_HUGE_VAL to something that works on your platform.
jpayne@69:  */
jpayne@69: #ifndef Py_HUGE_VAL
jpayne@69: #define Py_HUGE_VAL HUGE_VAL
jpayne@69: #endif
jpayne@69: 
jpayne@69: /* Py_NAN
jpayne@69:  * A value that evaluates to a NaN. On IEEE 754 platforms INF*0 or
jpayne@69:  * INF/INF works. Define Py_NO_NAN in pyconfig.h if your platform
jpayne@69:  * doesn't support NaNs.
jpayne@69:  */
jpayne@69: #if !defined(Py_NAN) && !defined(Py_NO_NAN)
jpayne@69: #if !defined(__INTEL_COMPILER)
jpayne@69:     #define Py_NAN (Py_HUGE_VAL * 0.)
jpayne@69: #else /* __INTEL_COMPILER */
jpayne@69:     #if defined(ICC_NAN_STRICT)
jpayne@69:         #pragma float_control(push)
jpayne@69:         #pragma float_control(precise, on)
jpayne@69:         #pragma float_control(except,  on)
jpayne@69:         #if defined(_MSC_VER)
jpayne@69:             __declspec(noinline)
jpayne@69:         #else /* Linux */
jpayne@69:             __attribute__((noinline))
jpayne@69:         #endif /* _MSC_VER */
jpayne@69:         static double __icc_nan()
jpayne@69:         {
jpayne@69:             return sqrt(-1.0);
jpayne@69:         }
jpayne@69:         #pragma float_control (pop)
jpayne@69:         #define Py_NAN __icc_nan()
jpayne@69:     #else /* ICC_NAN_RELAXED as default for Intel Compiler */
jpayne@69:         static const union { unsigned char buf[8]; double __icc_nan; } __nan_store = {0,0,0,0,0,0,0xf8,0x7f};
jpayne@69:         #define Py_NAN (__nan_store.__icc_nan)
jpayne@69:     #endif /* ICC_NAN_STRICT */
jpayne@69: #endif /* __INTEL_COMPILER */
jpayne@69: #endif
jpayne@69: 
jpayne@69: /* Py_OVERFLOWED(X)
jpayne@69:  * Return 1 iff a libm function overflowed.  Set errno to 0 before calling
jpayne@69:  * a libm function, and invoke this macro after, passing the function
jpayne@69:  * result.
jpayne@69:  * Caution:
jpayne@69:  *    This isn't reliable.  C99 no longer requires libm to set errno under
jpayne@69:  *        any exceptional condition, but does require +- HUGE_VAL return
jpayne@69:  *        values on overflow.  A 754 box *probably* maps HUGE_VAL to a
jpayne@69:  *        double infinity, and we're cool if that's so, unless the input
jpayne@69:  *        was an infinity and an infinity is the expected result.  A C89
jpayne@69:  *        system sets errno to ERANGE, so we check for that too.  We're
jpayne@69:  *        out of luck if a C99 754 box doesn't map HUGE_VAL to +Inf, or
jpayne@69:  *        if the returned result is a NaN, or if a C89 box returns HUGE_VAL
jpayne@69:  *        in non-overflow cases.
jpayne@69:  *    X is evaluated more than once.
jpayne@69:  * Some platforms have better way to spell this, so expect some #ifdef'ery.
jpayne@69:  *
jpayne@69:  * OpenBSD uses 'isinf()' because a compiler bug on that platform causes
jpayne@69:  * the longer macro version to be mis-compiled. This isn't optimal, and
jpayne@69:  * should be removed once a newer compiler is available on that platform.
jpayne@69:  * The system that had the failure was running OpenBSD 3.2 on Intel, with
jpayne@69:  * gcc 2.95.3.
jpayne@69:  *
jpayne@69:  * According to Tim's checkin, the FreeBSD systems use isinf() to work
jpayne@69:  * around a FPE bug on that platform.
jpayne@69:  */
jpayne@69: #if defined(__FreeBSD__) || defined(__OpenBSD__)
jpayne@69: #define Py_OVERFLOWED(X) isinf(X)
jpayne@69: #else
jpayne@69: #define Py_OVERFLOWED(X) ((X) != 0.0 && (errno == ERANGE ||    \
jpayne@69:                                          (X) == Py_HUGE_VAL || \
jpayne@69:                                          (X) == -Py_HUGE_VAL))
jpayne@69: #endif
jpayne@69: 
jpayne@69: /* Return whether integral type *type* is signed or not. */
jpayne@69: #define _Py_IntegralTypeSigned(type) ((type)(-1) < 0)
jpayne@69: /* Return the maximum value of integral type *type*. */
jpayne@69: #define _Py_IntegralTypeMax(type) ((_Py_IntegralTypeSigned(type)) ? (((((type)1 << (sizeof(type)*CHAR_BIT - 2)) - 1) << 1) + 1) : ~(type)0)
jpayne@69: /* Return the minimum value of integral type *type*. */
jpayne@69: #define _Py_IntegralTypeMin(type) ((_Py_IntegralTypeSigned(type)) ? -_Py_IntegralTypeMax(type) - 1 : 0)
jpayne@69: /* Check whether *v* is in the range of integral type *type*. This is most
jpayne@69:  * useful if *v* is floating-point, since demoting a floating-point *v* to an
jpayne@69:  * integral type that cannot represent *v*'s integral part is undefined
jpayne@69:  * behavior. */
jpayne@69: #define _Py_InIntegralTypeRange(type, v) (_Py_IntegralTypeMin(type) <= v && v <= _Py_IntegralTypeMax(type))
jpayne@69: 
jpayne@69: #endif /* Py_PYMATH_H */