/* Float object interface */ /*PyFloatObject represents a (double precision) floating point number.*/ #ifndef Py_FLOATOBJECT_H#define Py_FLOATOBJECT_H#ifdef __cplusplusextern "C" {#endif typedef struct {    PyObject_HEAD    double ob_fval;} PyFloatObject; PyAPI_DATA(PyTypeObject) PyFloat_Type; #define PyFloat_Check(op) PyObject_TypeCheck(op, &PyFloat_Type)#define PyFloat_CheckExact(op) ((op)->ob_type == &PyFloat_Type) /* Return Python float from string PyObject.  Second argument ignored on   input, and, if non-NULL, NULL is stored into *junk (this tried to serve a   purpose once but can't be made to work as intended). */PyAPI_FUNC(PyObject *) PyFloat_FromString(PyObject*, char** junk); /* Return Python float from C double. */PyAPI_FUNC(PyObject *) PyFloat_FromDouble(double); /* Extract C double from Python float.  The macro version trades safety for   speed. */PyAPI_FUNC(double) PyFloat_AsDouble(PyObject *);#define PyFloat_AS_DOUBLE(op) (((PyFloatObject *)(op))->ob_fval) /* Write repr(v) into the char buffer argument, followed by null byte.  The   buffer must be "big enough"; >= 100 is very safe.   PyFloat_AsReprString(buf, x) strives to print enough digits so that   PyFloat_FromString(buf) then reproduces x exactly. */PyAPI_FUNC(void) PyFloat_AsReprString(char*, PyFloatObject *v); /* Write str(v) into the char buffer argument, followed by null byte.  The   buffer must be "big enough"; >= 100 is very safe.  Note that it's   unusual to be able to get back the float you started with from   PyFloat_AsString's result -- use PyFloat_AsReprString() if you want to   preserve precision across conversions. */PyAPI_FUNC(void) PyFloat_AsString(char*, PyFloatObject *v); /* _PyFloat_{Pack,Unpack}{4,8} * * The struct and pickle (at least) modules need an efficient platform- * independent way to store floating-point values as byte strings. * The Pack routines produce a string from a C double, and the Unpack * routines produce a C double from such a string.  The suffix (4 or 8) * specifies the number of bytes in the string. * * On platforms that appear to use (see _PyFloat_Init()) IEEE-754 formats * these functions work by copying bits.  On other platforms, the formats the * 4- byte format is identical to the IEEE-754 single precision format, and * the 8-byte format to the IEEE-754 double precision format, although the * packing of INFs and NaNs (if such things exist on the platform) isn't * handled correctly, and attempting to unpack a string containing an IEEE * INF or NaN will raise an exception. * * On non-IEEE platforms with more precision, or larger dynamic range, than * 754 supports, not all values can be packed; on non-IEEE platforms with less * precision, or smaller dynamic range, not all values can be unpacked.  What * happens in such cases is partly accidental (alas). */ /* The pack routines write 4 or 8 bytes, starting at p.  le is a bool * argument, true if you want the string in little-endian format (exponent * last, at p+3 or p+7), false if you want big-endian format (exponent * first, at p). * Return value:  0 if all is OK, -1 if error (and an exception is * set, most likely OverflowError). * There are two problems on non-IEEE platforms: * 1):  What this does is undefined if x is a NaN or infinity. * 2):  -0.0 and +0.0 produce the same string. */PyAPI_FUNC(int) _PyFloat_Pack4(double x, unsigned char *p, int le);PyAPI_FUNC(int) _PyFloat_Pack8(double x, unsigned char *p, int le); /* The unpack routines read 4 or 8 bytes, starting at p.  le is a bool * argument, true if the string is in little-endian format (exponent * last, at p+3 or p+7), false if big-endian (exponent first, at p). * Return value:  The unpacked double.  On error, this is -1.0 and * PyErr_Occurred() is true (and an exception is set, most likely * OverflowError).  Note that on a non-IEEE platform this will refuse * to unpack a string that represents a NaN or infinity. */PyAPI_FUNC(double) _PyFloat_Unpack4(const unsigned char *p, int le);PyAPI_FUNC(double) _PyFloat_Unpack8(const unsigned char *p, int le);  #ifdef __cplusplus}#endif#endif /* !Py_FLOATOBJECT_H */