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			130 lines
		
	
	
	
		
			4.7 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			130 lines
		
	
	
	
		
			4.7 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| 
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| /* Float object interface */
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| 
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| /*
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| PyFloatObject represents a (double precision) floating point number.
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| */
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| 
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| #ifndef Py_FLOATOBJECT_H
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| #define Py_FLOATOBJECT_H
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| #ifdef __cplusplus
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| extern "C" {
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| #endif
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| 
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| #ifndef Py_LIMITED_API
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| typedef struct {
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|     PyObject_HEAD
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|     double ob_fval;
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| } PyFloatObject;
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| #endif
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| 
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| PyAPI_DATA(PyTypeObject) PyFloat_Type;
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| 
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| #define PyFloat_Check(op) PyObject_TypeCheck(op, &PyFloat_Type)
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| #define PyFloat_CheckExact(op) (Py_TYPE(op) == &PyFloat_Type)
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| 
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| #ifdef Py_NAN
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| #define Py_RETURN_NAN return PyFloat_FromDouble(Py_NAN)
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| #endif
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| 
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| #define Py_RETURN_INF(sign) do                     \
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|     if (copysign(1., sign) == 1.) {                \
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|         return PyFloat_FromDouble(Py_HUGE_VAL);    \
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|     } else {                        \
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|         return PyFloat_FromDouble(-Py_HUGE_VAL);   \
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|     } while(0)
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| 
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| PyAPI_FUNC(double) PyFloat_GetMax(void);
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| PyAPI_FUNC(double) PyFloat_GetMin(void);
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| PyAPI_FUNC(PyObject *) PyFloat_GetInfo(void);
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| 
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| /* Return Python float from string PyObject. */
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| PyAPI_FUNC(PyObject *) PyFloat_FromString(PyObject*);
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| 
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| /* Return Python float from C double. */
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| PyAPI_FUNC(PyObject *) PyFloat_FromDouble(double);
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| 
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| /* Extract C double from Python float.  The macro version trades safety for
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|    speed. */
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| PyAPI_FUNC(double) PyFloat_AsDouble(PyObject *);
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| #ifndef Py_LIMITED_API
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| #define PyFloat_AS_DOUBLE(op) (((PyFloatObject *)(op))->ob_fval)
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| #endif
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| 
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| #ifndef Py_LIMITED_API
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| /* _PyFloat_{Pack,Unpack}{4,8}
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|  *
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|  * The struct and pickle (at least) modules need an efficient platform-
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|  * independent way to store floating-point values as byte strings.
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|  * The Pack routines produce a string from a C double, and the Unpack
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|  * routines produce a C double from such a string.  The suffix (4 or 8)
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|  * specifies the number of bytes in the string.
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|  *
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|  * On platforms that appear to use (see _PyFloat_Init()) IEEE-754 formats
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|  * these functions work by copying bits.  On other platforms, the formats the
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|  * 4- byte format is identical to the IEEE-754 single precision format, and
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|  * the 8-byte format to the IEEE-754 double precision format, although the
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|  * packing of INFs and NaNs (if such things exist on the platform) isn't
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|  * handled correctly, and attempting to unpack a string containing an IEEE
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|  * INF or NaN will raise an exception.
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|  *
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|  * On non-IEEE platforms with more precision, or larger dynamic range, than
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|  * 754 supports, not all values can be packed; on non-IEEE platforms with less
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|  * precision, or smaller dynamic range, not all values can be unpacked.  What
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|  * happens in such cases is partly accidental (alas).
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|  */
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| 
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| /* The pack routines write 2, 4 or 8 bytes, starting at p.  le is a bool
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|  * argument, true if you want the string in little-endian format (exponent
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|  * last, at p+1, p+3 or p+7), false if you want big-endian format (exponent
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|  * first, at p).
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|  * Return value:  0 if all is OK, -1 if error (and an exception is
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|  * set, most likely OverflowError).
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|  * There are two problems on non-IEEE platforms:
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|  * 1):  What this does is undefined if x is a NaN or infinity.
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|  * 2):  -0.0 and +0.0 produce the same string.
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|  */
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| PyAPI_FUNC(int) _PyFloat_Pack2(double x, unsigned char *p, int le);
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| PyAPI_FUNC(int) _PyFloat_Pack4(double x, unsigned char *p, int le);
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| PyAPI_FUNC(int) _PyFloat_Pack8(double x, unsigned char *p, int le);
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| 
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| /* Needed for the old way for marshal to store a floating point number.
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|    Returns the string length copied into p, -1 on error.
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|  */
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| PyAPI_FUNC(int) _PyFloat_Repr(double x, char *p, size_t len);
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| 
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| /* Used to get the important decimal digits of a double */
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| PyAPI_FUNC(int) _PyFloat_Digits(char *buf, double v, int *signum);
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| PyAPI_FUNC(void) _PyFloat_DigitsInit(void);
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| 
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| /* The unpack routines read 2, 4 or 8 bytes, starting at p.  le is a bool
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|  * argument, true if the string is in little-endian format (exponent
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|  * last, at p+1, p+3 or p+7), false if big-endian (exponent first, at p).
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|  * Return value:  The unpacked double.  On error, this is -1.0 and
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|  * PyErr_Occurred() is true (and an exception is set, most likely
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|  * OverflowError).  Note that on a non-IEEE platform this will refuse
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|  * to unpack a string that represents a NaN or infinity.
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|  */
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| PyAPI_FUNC(double) _PyFloat_Unpack2(const unsigned char *p, int le);
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| PyAPI_FUNC(double) _PyFloat_Unpack4(const unsigned char *p, int le);
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| PyAPI_FUNC(double) _PyFloat_Unpack8(const unsigned char *p, int le);
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| 
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| /* free list api */
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| PyAPI_FUNC(int) PyFloat_ClearFreeList(void);
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| 
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| PyAPI_FUNC(void) _PyFloat_DebugMallocStats(FILE* out);
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| 
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| /* Format the object based on the format_spec, as defined in PEP 3101
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|    (Advanced String Formatting). */
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| PyAPI_FUNC(int) _PyFloat_FormatAdvancedWriter(
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|     _PyUnicodeWriter *writer,
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|     PyObject *obj,
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|     PyObject *format_spec,
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|     Py_ssize_t start,
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|     Py_ssize_t end);
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| #endif /* Py_LIMITED_API */
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| 
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| #ifdef __cplusplus
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| }
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| #endif
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| #endif /* !Py_FLOATOBJECT_H */
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