annotate DEPENDENCIES/mingw32/Python27/include/floatobject.h @ 118:770eb830ec19 emscripten

Typo fix
author Chris Cannam
date Wed, 18 May 2016 16:14:08 +0100
parents 2a2c65a20a8b
children
rev   line source
Chris@87 1
Chris@87 2 /* Float object interface */
Chris@87 3
Chris@87 4 /*
Chris@87 5 PyFloatObject represents a (double precision) floating point number.
Chris@87 6 */
Chris@87 7
Chris@87 8 #ifndef Py_FLOATOBJECT_H
Chris@87 9 #define Py_FLOATOBJECT_H
Chris@87 10 #ifdef __cplusplus
Chris@87 11 extern "C" {
Chris@87 12 #endif
Chris@87 13
Chris@87 14 typedef struct {
Chris@87 15 PyObject_HEAD
Chris@87 16 double ob_fval;
Chris@87 17 } PyFloatObject;
Chris@87 18
Chris@87 19 PyAPI_DATA(PyTypeObject) PyFloat_Type;
Chris@87 20
Chris@87 21 #define PyFloat_Check(op) PyObject_TypeCheck(op, &PyFloat_Type)
Chris@87 22 #define PyFloat_CheckExact(op) (Py_TYPE(op) == &PyFloat_Type)
Chris@87 23
Chris@87 24 /* The str() precision PyFloat_STR_PRECISION is chosen so that in most cases,
Chris@87 25 the rounding noise created by various operations is suppressed, while
Chris@87 26 giving plenty of precision for practical use. */
Chris@87 27
Chris@87 28 #define PyFloat_STR_PRECISION 12
Chris@87 29
Chris@87 30 #ifdef Py_NAN
Chris@87 31 #define Py_RETURN_NAN return PyFloat_FromDouble(Py_NAN)
Chris@87 32 #endif
Chris@87 33
Chris@87 34 #define Py_RETURN_INF(sign) do \
Chris@87 35 if (copysign(1., sign) == 1.) { \
Chris@87 36 return PyFloat_FromDouble(Py_HUGE_VAL); \
Chris@87 37 } else { \
Chris@87 38 return PyFloat_FromDouble(-Py_HUGE_VAL); \
Chris@87 39 } while(0)
Chris@87 40
Chris@87 41 PyAPI_FUNC(double) PyFloat_GetMax(void);
Chris@87 42 PyAPI_FUNC(double) PyFloat_GetMin(void);
Chris@87 43 PyAPI_FUNC(PyObject *) PyFloat_GetInfo(void);
Chris@87 44
Chris@87 45 /* Return Python float from string PyObject. Second argument ignored on
Chris@87 46 input, and, if non-NULL, NULL is stored into *junk (this tried to serve a
Chris@87 47 purpose once but can't be made to work as intended). */
Chris@87 48 PyAPI_FUNC(PyObject *) PyFloat_FromString(PyObject*, char** junk);
Chris@87 49
Chris@87 50 /* Return Python float from C double. */
Chris@87 51 PyAPI_FUNC(PyObject *) PyFloat_FromDouble(double);
Chris@87 52
Chris@87 53 /* Extract C double from Python float. The macro version trades safety for
Chris@87 54 speed. */
Chris@87 55 PyAPI_FUNC(double) PyFloat_AsDouble(PyObject *);
Chris@87 56 #define PyFloat_AS_DOUBLE(op) (((PyFloatObject *)(op))->ob_fval)
Chris@87 57
Chris@87 58 /* Write repr(v) into the char buffer argument, followed by null byte. The
Chris@87 59 buffer must be "big enough"; >= 100 is very safe.
Chris@87 60 PyFloat_AsReprString(buf, x) strives to print enough digits so that
Chris@87 61 PyFloat_FromString(buf) then reproduces x exactly. */
Chris@87 62 PyAPI_FUNC(void) PyFloat_AsReprString(char*, PyFloatObject *v);
Chris@87 63
Chris@87 64 /* Write str(v) into the char buffer argument, followed by null byte. The
Chris@87 65 buffer must be "big enough"; >= 100 is very safe. Note that it's
Chris@87 66 unusual to be able to get back the float you started with from
Chris@87 67 PyFloat_AsString's result -- use PyFloat_AsReprString() if you want to
Chris@87 68 preserve precision across conversions. */
Chris@87 69 PyAPI_FUNC(void) PyFloat_AsString(char*, PyFloatObject *v);
Chris@87 70
Chris@87 71 /* _PyFloat_{Pack,Unpack}{4,8}
Chris@87 72 *
Chris@87 73 * The struct and pickle (at least) modules need an efficient platform-
Chris@87 74 * independent way to store floating-point values as byte strings.
Chris@87 75 * The Pack routines produce a string from a C double, and the Unpack
Chris@87 76 * routines produce a C double from such a string. The suffix (4 or 8)
Chris@87 77 * specifies the number of bytes in the string.
Chris@87 78 *
Chris@87 79 * On platforms that appear to use (see _PyFloat_Init()) IEEE-754 formats
Chris@87 80 * these functions work by copying bits. On other platforms, the formats the
Chris@87 81 * 4- byte format is identical to the IEEE-754 single precision format, and
Chris@87 82 * the 8-byte format to the IEEE-754 double precision format, although the
Chris@87 83 * packing of INFs and NaNs (if such things exist on the platform) isn't
Chris@87 84 * handled correctly, and attempting to unpack a string containing an IEEE
Chris@87 85 * INF or NaN will raise an exception.
Chris@87 86 *
Chris@87 87 * On non-IEEE platforms with more precision, or larger dynamic range, than
Chris@87 88 * 754 supports, not all values can be packed; on non-IEEE platforms with less
Chris@87 89 * precision, or smaller dynamic range, not all values can be unpacked. What
Chris@87 90 * happens in such cases is partly accidental (alas).
Chris@87 91 */
Chris@87 92
Chris@87 93 /* The pack routines write 4 or 8 bytes, starting at p. le is a bool
Chris@87 94 * argument, true if you want the string in little-endian format (exponent
Chris@87 95 * last, at p+3 or p+7), false if you want big-endian format (exponent
Chris@87 96 * first, at p).
Chris@87 97 * Return value: 0 if all is OK, -1 if error (and an exception is
Chris@87 98 * set, most likely OverflowError).
Chris@87 99 * There are two problems on non-IEEE platforms:
Chris@87 100 * 1): What this does is undefined if x is a NaN or infinity.
Chris@87 101 * 2): -0.0 and +0.0 produce the same string.
Chris@87 102 */
Chris@87 103 PyAPI_FUNC(int) _PyFloat_Pack4(double x, unsigned char *p, int le);
Chris@87 104 PyAPI_FUNC(int) _PyFloat_Pack8(double x, unsigned char *p, int le);
Chris@87 105
Chris@87 106 /* Used to get the important decimal digits of a double */
Chris@87 107 PyAPI_FUNC(int) _PyFloat_Digits(char *buf, double v, int *signum);
Chris@87 108 PyAPI_FUNC(void) _PyFloat_DigitsInit(void);
Chris@87 109
Chris@87 110 /* The unpack routines read 4 or 8 bytes, starting at p. le is a bool
Chris@87 111 * argument, true if the string is in little-endian format (exponent
Chris@87 112 * last, at p+3 or p+7), false if big-endian (exponent first, at p).
Chris@87 113 * Return value: The unpacked double. On error, this is -1.0 and
Chris@87 114 * PyErr_Occurred() is true (and an exception is set, most likely
Chris@87 115 * OverflowError). Note that on a non-IEEE platform this will refuse
Chris@87 116 * to unpack a string that represents a NaN or infinity.
Chris@87 117 */
Chris@87 118 PyAPI_FUNC(double) _PyFloat_Unpack4(const unsigned char *p, int le);
Chris@87 119 PyAPI_FUNC(double) _PyFloat_Unpack8(const unsigned char *p, int le);
Chris@87 120
Chris@87 121 /* free list api */
Chris@87 122 PyAPI_FUNC(int) PyFloat_ClearFreeList(void);
Chris@87 123
Chris@87 124 /* Format the object based on the format_spec, as defined in PEP 3101
Chris@87 125 (Advanced String Formatting). */
Chris@87 126 PyAPI_FUNC(PyObject *) _PyFloat_FormatAdvanced(PyObject *obj,
Chris@87 127 char *format_spec,
Chris@87 128 Py_ssize_t format_spec_len);
Chris@87 129
Chris@87 130 /* Round a C double x to the closest multiple of 10**-ndigits. Returns a
Chris@87 131 Python float on success, or NULL (with an appropriate exception set) on
Chris@87 132 failure. Used in builtin_round in bltinmodule.c. */
Chris@87 133 PyAPI_FUNC(PyObject *) _Py_double_round(double x, int ndigits);
Chris@87 134
Chris@87 135
Chris@87 136
Chris@87 137 #ifdef __cplusplus
Chris@87 138 }
Chris@87 139 #endif
Chris@87 140 #endif /* !Py_FLOATOBJECT_H */