diff options
Diffstat (limited to 'Modules/mathmodule.c')
| -rw-r--r-- | Modules/mathmodule.c | 83 |
1 files changed, 80 insertions, 3 deletions
diff --git a/Modules/mathmodule.c b/Modules/mathmodule.c index 11d9b7418a2..033de0b2907 100644 --- a/Modules/mathmodule.c +++ b/Modules/mathmodule.c @@ -1233,6 +1233,23 @@ FUNC2(remainder, m_remainder, "Return x - n*y where n*y is the closest integer multiple of y.\n" "In the case where x is exactly halfway between two multiples of\n" "y, the nearest even value of n is used. The result is always exact.") + +/*[clinic input] +math.signbit + + x: double + / + +Return True if the sign of x is negative and False otherwise. +[clinic start generated code]*/ + +static PyObject * +math_signbit_impl(PyObject *module, double x) +/*[clinic end generated code: output=20c5f20156a9b871 input=3d3493fbcb5bdb3e]*/ +{ + return PyBool_FromLong(signbit(x)); +} + FUNC1D(sin, sin, 0, "sin($module, x, /)\n--\n\n" "Return the sine of x (measured in radians).", @@ -2008,13 +2025,11 @@ math.factorial / Find n!. - -Raise a ValueError if x is negative or non-integral. [clinic start generated code]*/ static PyObject * math_factorial(PyObject *module, PyObject *arg) -/*[clinic end generated code: output=6686f26fae00e9ca input=713fb771677e8c31]*/ +/*[clinic end generated code: output=6686f26fae00e9ca input=366cc321df3d4773]*/ { long x, two_valuation; int overflow; @@ -2163,6 +2178,27 @@ math_ldexp_impl(PyObject *module, double x, PyObject *i) } else { errno = 0; r = ldexp(x, (int)exp); +#ifdef _MSC_VER + if (DBL_MIN > r && r > -DBL_MIN) { + /* Denormal (or zero) results can be incorrectly rounded here (rather, + truncated). Fixed in newer versions of the C runtime, included + with Windows 11. */ + int original_exp; + frexp(x, &original_exp); + if (original_exp > DBL_MIN_EXP) { + /* Shift down to the smallest normal binade. No bits lost. */ + int shift = DBL_MIN_EXP - original_exp; + x = ldexp(x, shift); + exp -= shift; + } + /* Multiplying by 2**exp finishes the job, and the HW will round as + appropriate. Note: if exp < -DBL_MANT_DIG, all of x is shifted + to be < 0.5ULP of smallest denorm, so should be thrown away. If + exp is so very negative that ldexp underflows to 0, that's fine; + no need to check in advance. */ + r = x*ldexp(1.0, (int)exp); + } +#endif if (isinf(r)) errno = ERANGE; } @@ -3100,6 +3136,44 @@ math_isfinite_impl(PyObject *module, double x) /*[clinic input] +math.isnormal + + x: double + / + +Return True if x is normal, and False otherwise. +[clinic start generated code]*/ + +static PyObject * +math_isnormal_impl(PyObject *module, double x) +/*[clinic end generated code: output=c7b302b5b89c3541 input=fdaa00c58aa7bc17]*/ +{ + return PyBool_FromLong(isnormal(x)); +} + + +/*[clinic input] +math.issubnormal + + x: double + / + +Return True if x is subnormal, and False otherwise. +[clinic start generated code]*/ + +static PyObject * +math_issubnormal_impl(PyObject *module, double x) +/*[clinic end generated code: output=4e76ac98ddcae761 input=9a20aba7107d0d95]*/ +{ +#if !defined(_MSC_VER) && defined(__STDC_VERSION__) && __STDC_VERSION__ >= 202311L + return PyBool_FromLong(issubnormal(x)); +#else + return PyBool_FromLong(isfinite(x) && x && !isnormal(x)); +#endif +} + + +/*[clinic input] math.isnan x: double @@ -4126,6 +4200,8 @@ static PyMethodDef math_methods[] = { MATH_HYPOT_METHODDEF MATH_ISCLOSE_METHODDEF MATH_ISFINITE_METHODDEF + MATH_ISNORMAL_METHODDEF + MATH_ISSUBNORMAL_METHODDEF MATH_ISINF_METHODDEF MATH_ISNAN_METHODDEF MATH_ISQRT_METHODDEF @@ -4140,6 +4216,7 @@ static PyMethodDef math_methods[] = { MATH_POW_METHODDEF MATH_RADIANS_METHODDEF {"remainder", _PyCFunction_CAST(math_remainder), METH_FASTCALL, math_remainder_doc}, + MATH_SIGNBIT_METHODDEF {"sin", math_sin, METH_O, math_sin_doc}, {"sinh", math_sinh, METH_O, math_sinh_doc}, {"sqrt", math_sqrt, METH_O, math_sqrt_doc}, |