diff options
| -rw-r--r-- | Doc/c-api/concrete.rst | 2 | ||||
| -rw-r--r-- | Doc/library/sys.rst | 4 | ||||
| -rw-r--r-- | Lib/test/test_sys.py | 2 | ||||
| -rw-r--r-- | Misc/NEWS | 3 | ||||
| -rw-r--r-- | Objects/floatobject.c | 107 |
5 files changed, 85 insertions, 33 deletions
diff --git a/Doc/c-api/concrete.rst b/Doc/c-api/concrete.rst index 713daab..623df36 100644 --- a/Doc/c-api/concrete.rst +++ b/Doc/c-api/concrete.rst @@ -559,7 +559,7 @@ Floating Point Objects .. cfunction:: PyObject* PyFloat_GetInfo(void) - Return a :ctype:`PyDictObject` object which contains information about the + Return a structseq instance which contains information about the precision, minimum and maximum values of a float. It's a thin wrapper around the header file :file:`float.h`. diff --git a/Doc/library/sys.rst b/Doc/library/sys.rst index d830490..7dbf41e 100644 --- a/Doc/library/sys.rst +++ b/Doc/library/sys.rst @@ -280,12 +280,12 @@ always available. .. data:: float_info - A dict holding information about the float type. It contains low level + A structseq holding information about the float type. It contains low level information about the precision and internal representation. Please study your system's :file:`float.h` for more information. +---------------------+--------------------------------------------------+ - | key | explanation | + | attribute | explanation | +=====================+==================================================+ | :const:`epsilon` | Difference between 1 and the next representable | | | floating point number | diff --git a/Lib/test/test_sys.py b/Lib/test/test_sys.py index 66710a0..1b9b9d0 100644 --- a/Lib/test/test_sys.py +++ b/Lib/test/test_sys.py @@ -329,8 +329,8 @@ class SysModuleTest(unittest.TestCase): self.assert_(isinstance(sys.copyright, basestring)) self.assert_(isinstance(sys.exec_prefix, basestring)) self.assert_(isinstance(sys.executable, basestring)) - self.assert_(isinstance(sys.float_info, dict)) self.assertEqual(len(sys.float_info), 11) + self.assertEqual(sys.float_info.radix, 2) self.assert_(isinstance(sys.hexversion, int)) self.assert_(isinstance(sys.maxint, int)) if test.test_support.have_unicode: @@ -12,6 +12,9 @@ What's New in Python 2.6 alpha 1? Core and builtins ----------------- +- sys.float_info / PyFloat_GetInfo: The floating point information + object was converted from a dict to a specialized structseq object. + - Patch #1816: Added sys.flags structseq. It exposes the status of most command line arguments and PYTHON* environment variables. diff --git a/Objects/floatobject.c b/Objects/floatobject.c index ff23d33..340b0e7 100644 --- a/Objects/floatobject.c +++ b/Objects/floatobject.c @@ -5,10 +5,12 @@ for any kind of float exception without losing portability. */ #include "Python.h" +#include "structseq.h" #include <ctype.h> #include <float.h> + #if !defined(__STDC__) extern double fmod(double, double); extern double pow(double, double); @@ -59,39 +61,86 @@ PyFloat_GetMin(void) return DBL_MIN; } +static PyTypeObject FloatInfoType = {0}; + +PyDoc_STRVAR(floatinfo__doc__, +"sys.floatinfo\n\ +\n\ +A structseq holding information about the float type. It contains low level\n\ +information about the precision and internal representation. Please study\n\ +your system's :file:`float.h` for more information."); + +static PyStructSequence_Field floatinfo_fields[] = { + {"max", "DBL_MAX -- maximum representable finite float"}, + {"max_exp", "DBL_MAX_EXP -- maximum int e such that radix**(e-1) " + "is representable"}, + {"max_10_exp", "DBL_MAX_10_EXP -- maximum int e such that 10**e " + "is representable"}, + {"min", "DBL_MIN -- Minimum positive normalizer float"}, + {"min_exp", "DBL_MIN_EXP -- minimum int e such that radix**(e-1) " + "is a normalized float"}, + {"min_10_exp", "DBL_MIN_10_EXP -- minimum int e such that 10**e is " + "a normalized"}, + {"dig", "DBL_DIG -- digits"}, + {"mant_dig", "DBL_MANT_DIG -- mantissa digits"}, + {"epsilon", "DBL_EPSILON -- Difference between 1 and the next " + "representable float"}, + {"radix", "FLT_RADIX -- radix of exponent"}, + {"rounds", "FLT_ROUNDS -- addition rounds"}, + {0} +}; + +static PyStructSequence_Desc floatinfo_desc = { + "sys.floatinfo", /* name */ + floatinfo__doc__, /* doc */ + floatinfo_fields, /* fields */ + 11 +}; + PyObject * PyFloat_GetInfo(void) { - PyObject *d, *tmp; - -#define SET_FLOAT_CONST(d, key, const) \ - tmp = PyFloat_FromDouble(const); \ - if (tmp == NULL) return NULL; \ - if (PyDict_SetItemString(d, key, tmp)) return NULL; \ - Py_DECREF(tmp) -#define SET_INT_CONST(d, key, const) \ - tmp = PyInt_FromLong(const); \ - if (tmp == NULL) return NULL; \ - if (PyDict_SetItemString(d, key, tmp)) return NULL; \ - Py_DECREF(tmp) - - d = PyDict_New(); - - SET_FLOAT_CONST(d, "max", DBL_MAX); - SET_INT_CONST(d, "max_exp", DBL_MAX_EXP); - SET_INT_CONST(d, "max_10_exp", DBL_MAX_10_EXP); - SET_FLOAT_CONST(d, "min", DBL_MIN); - SET_INT_CONST(d, "min_exp", DBL_MIN_EXP); - SET_INT_CONST(d, "min_10_exp", DBL_MIN_10_EXP); - SET_INT_CONST(d, "dig", DBL_DIG); - SET_INT_CONST(d, "mant_dig", DBL_MANT_DIG); - SET_FLOAT_CONST(d, "epsilon", DBL_EPSILON); - SET_INT_CONST(d, "radix", FLT_RADIX); - SET_INT_CONST(d, "rounds", FLT_ROUNDS); - - return d; -} + static PyObject* floatinfo; + int pos = 0; + + if (floatinfo != NULL) { + Py_INCREF(floatinfo); + return floatinfo; + } + PyStructSequence_InitType(&FloatInfoType, &floatinfo_desc); + + floatinfo = PyStructSequence_New(&FloatInfoType); + if (floatinfo == NULL) { + return NULL; + } +#define SetIntFlag(flag) \ + PyStructSequence_SET_ITEM(floatinfo, pos++, PyInt_FromLong(flag)) +#define SetDblFlag(flag) \ + PyStructSequence_SET_ITEM(floatinfo, pos++, PyFloat_FromDouble(flag)) + + SetDblFlag(DBL_MAX); + SetIntFlag(DBL_MAX_EXP); + SetIntFlag(DBL_MAX_10_EXP); + SetDblFlag(DBL_MIN); + SetIntFlag(DBL_MIN_EXP); + SetIntFlag(DBL_MIN_10_EXP); + SetIntFlag(DBL_DIG); + SetIntFlag(DBL_MANT_DIG); + SetDblFlag(DBL_EPSILON); + SetIntFlag(FLT_RADIX); + SetIntFlag(FLT_ROUNDS); +#undef SetIntFlag +#undef SetDblFlag + + if (PyErr_Occurred()) { + Py_CLEAR(floatinfo); + return NULL; + } + + Py_INCREF(floatinfo); + return floatinfo; +} PyObject * PyFloat_FromDouble(double fval) |