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/* Float object interface */ 
 
/* 
PyFloatObject represents a (double precision) floating point number. 
*/ 
 
#ifndef Py_FLOATOBJECT_H 
#define Py_FLOATOBJECT_H 
#ifdef __cplusplus 
extern "C" { 
#endif 
 
#ifndef Py_LIMITED_API 
typedef struct { 
    PyObject_HEAD 
    double ob_fval; 
} PyFloatObject; 
#endif 
 
PyAPI_DATA(PyTypeObject) PyFloat_Type; 
 
#define PyFloat_Check(op) PyObject_TypeCheck(op, &PyFloat_Type) 
#define PyFloat_CheckExact(op) Py_IS_TYPE(op, &PyFloat_Type)
 
#ifdef Py_NAN 
#define Py_RETURN_NAN return PyFloat_FromDouble(Py_NAN) 
#endif 
 
#define Py_RETURN_INF(sign) do                     \ 
    if (copysign(1., sign) == 1.) {                \ 
        return PyFloat_FromDouble(Py_HUGE_VAL);    \ 
    } else {                        \ 
        return PyFloat_FromDouble(-Py_HUGE_VAL);   \ 
    } while(0) 
 
PyAPI_FUNC(double) PyFloat_GetMax(void); 
PyAPI_FUNC(double) PyFloat_GetMin(void); 
PyAPI_FUNC(PyObject *) PyFloat_GetInfo(void); 
 
/* Return Python float from string PyObject. */ 
PyAPI_FUNC(PyObject *) PyFloat_FromString(PyObject*); 
 
/* 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 *); 
#ifndef Py_LIMITED_API 
#define PyFloat_AS_DOUBLE(op) (((PyFloatObject *)(op))->ob_fval) 
#endif 
 
#ifndef Py_LIMITED_API 
/* _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 2, 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+1, 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_Pack2(double x, unsigned char *p, int le); 
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 2, 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+1, 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_Unpack2(const unsigned char *p, int le); 
PyAPI_FUNC(double) _PyFloat_Unpack4(const unsigned char *p, int le); 
PyAPI_FUNC(double) _PyFloat_Unpack8(const unsigned char *p, int le); 
 
PyAPI_FUNC(void) _PyFloat_DebugMallocStats(FILE* out); 
 
/* Format the object based on the format_spec, as defined in PEP 3101 
   (Advanced String Formatting). */ 
PyAPI_FUNC(int) _PyFloat_FormatAdvancedWriter( 
    _PyUnicodeWriter *writer, 
    PyObject *obj, 
    PyObject *format_spec, 
    Py_ssize_t start, 
    Py_ssize_t end); 
#endif /* Py_LIMITED_API */ 
 
#ifdef __cplusplus 
} 
#endif 
#endif /* !Py_FLOATOBJECT_H */