python __builtins__ float类 （25）

25、'float', 用于将整数和字符串转换成浮点数。

class float(object)
 |  float(x) -> floating point number
 |
 |  Convert a string or number to a floating point number, if possible.
 |
 |  Methods defined here:
 |
 |  __abs__(self, /)
 |      abs(self)
 |
 |  __add__(self, value, /)
 |      Return self+value.
 |
 |  __bool__(self, /)
 |      self != 0
 |
 |  __divmod__(self, value, /)
 |      Return divmod(self, value).
 |
 |  __eq__(self, value, /)
 |      Return self==value.
 |
 |  __float__(self, /)
 |      float(self)
 |
 |  __floordiv__(self, value, /)
 |      Return self//value.
 |
 |  __format__(...)
 |      float.__format__(format_spec) -> string
 |
 |      Formats the float according to format_spec.
 |
 |  __ge__(self, value, /)
 |      Return self>=value.
 |
 |  __getattribute__(self, name, /)
 |      Return getattr(self, name).
 |
 |  __getformat__(...) from builtins.type
 |      float.__getformat__(typestr) -> string
 |
 |      You probably don't want to use this function.  It exists mainly to be
 |      used in Python's test suite.
 |
 |      typestr must be 'double' or 'float'.  This function returns whichever of
 |      'unknown', 'IEEE, big-endian' or 'IEEE, little-endian' best describes the
 |      format of floating point numbers used by the C type named by typestr.
 |
 |  __getnewargs__(...)
 |
 |  __gt__(self, value, /)
 |      Return self>value.
 |
 |  __hash__(self, /)
 |      Return hash(self).
 |
 |  __int__(self, /)
 |      int(self)
 |
 |  __le__(self, value, /)
 |      Return self<=value.
 |
 |  __lt__(self, value, /)
 |      Return self<value.
 |
 |  __mod__(self, value, /)
 |      Return self%value.
 |
 |  __mul__(self, value, /)
 |      Return self*value.
 |
 |  __ne__(self, value, /)
 |      Return self!=value.
 |
 |  __neg__(self, /)
 |      -self
 |
 |  __new__(*args, **kwargs) from builtins.type
 |      Create and return a new object.  See help(type) for accurate signature.
 |
 |  __pos__(self, /)
 |      +self
 |
 |  __pow__(self, value, mod=None, /)
 |      Return pow(self, value, mod).
 |
 |  __radd__(self, value, /)
 |      Return value+self.
 |
 |  __rdivmod__(self, value, /)
 |      Return divmod(value, self).
 |
 |  __repr__(self, /)
 |      Return repr(self).
 |
 |  __rfloordiv__(self, value, /)
 |      Return value//self.
 |
 |  __rmod__(self, value, /)
 |      Return value%self.
 |
 |  __rmul__(self, value, /)
 |      Return value*self.
 |
 |  __round__(...)
 |      Return the Integral closest to x, rounding half toward even.
 |      When an argument is passed, work like built-in round(x, ndigits).
 |
 |  __rpow__(self, value, mod=None, /)
 |      Return pow(value, self, mod).
 |
 |  __rsub__(self, value, /)
 |      Return value-self.
 |
 |  __rtruediv__(self, value, /)
 |      Return value/self.
 |
 |  __setformat__(...) from builtins.type
 |      float.__setformat__(typestr, fmt) -> None
 |
 |      You probably don't want to use this function.  It exists mainly to be
 |      used in Python's test suite.
 |
 |      typestr must be 'double' or 'float'.  fmt must be one of 'unknown',
 |      'IEEE, big-endian' or 'IEEE, little-endian', and in addition can only be
 |      one of the latter two if it appears to match the underlying C reality.
 |
 |      Override the automatic determination of C-level floating point type.
 |      This affects how floats are converted to and from binary strings.
 |
 |  __str__(self, /)
 |      Return str(self).
 |
 |  __sub__(self, value, /)
 |      Return self-value.
 |
 |  __truediv__(self, value, /)
 |      Return self/value.
 |
 |  __trunc__(...)
 |      Return the Integral closest to x between 0 and x.
 |
 |  as_integer_ratio(...)
 |      float.as_integer_ratio() -> (int, int)
 |
 |      Return a pair of integers, whose ratio is exactly equal to the original
 |      float and with a positive denominator.
 |      Raise OverflowError on infinities and a ValueError on NaNs.
 |
 |      >>> (10.0).as_integer_ratio()
 |      (10, 1)
 |      >>> (0.0).as_integer_ratio()
 |      (0, 1)
 |      >>> (-.25).as_integer_ratio()
 |      (-1, 4)
 |
 |  conjugate(...)
 |      Return self, the complex conjugate of any float.
 |
 |  fromhex(...) from builtins.type
 |      float.fromhex(string) -> float
 |
 |      Create a floating-point number from a hexadecimal string.
 |      >>> float.fromhex('0x1.ffffp10')
 |      2047.984375
 |      >>> float.fromhex('-0x1p-1074')
 |      -5e-324
 |
 |  hex(...)
 |      float.hex() -> string
 |
 |      Return a hexadecimal representation of a floating-point number.
 |      >>> (-0.1).hex()
 |      '-0x1.999999999999ap-4'
 |      >>> 3.14159.hex()
 |      '0x1.921f9f01b866ep+1'
 |
 |  is_integer(...)
 |      Return True if the float is an integer.
 |
 |  ----------------------------------------------------------------------
 |  Data descriptors defined here:
 |
 |  imag
 |      the imaginary part of a complex number
 |
 |  real
 |      the real part of a complex number