Python built-in function 5-float ()

Help on class float in module __builtin__:

class Float (object)

| Floating point number, float (x)

|

| Convert a string or number to a floating point number, if possible.

|

| Methods defined here:

|

| __abs__ (...)

| x.__abs__ () <==> ABS (x)

|

| __add__ (...)

| x.__add__ (y) <==> x+y

|

| __coerce__ (...)

| x.__coerce__ (y) <==> coerce (x, y)

|

| __div__ (...)

| x.__div__ (y) <==> x/y

|

| __divmod__ (...)

| x.__divmod__ (y) <==> divmod (x, y)

|

| __eq__ (...)

| x.__eq__ (y) <==> x==y

|

| __float__ (...)

| x.__float__ () <==> float (x)

|

| __floordiv__ (...)

| x.__floordiv__ (y) <==> x//y

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| __format__ (...)

| Float.__format__ (Format_spec), string

|

| Formats the float according to Format_spec.

|

| __ge__ (...)

| x.__ge__ (y) <==> x>=y

|

| __getattribute__ (...)

| x.__getattribute__ (' name ') <==> x.name

|

| __getformat__ (...)

| Float.__getformat__ (TYPESTR), string

|

|  You probably don ' t want the use of 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__ (...)

| x.__gt__ (y) <==> x>y

|

| __hash__ (...)

| x.__hash__ () <==> hash (x)

|

| __int__ (...)

| x.__int__ () <==> int (x)

|

| __le__ (...)

| x.__le__ (y) <==> x<=y

|

| __long__ (...)

| x.__long__ () <==> long (x)

|

| __lt__ (...)

| x.__lt__ (y) <==> x<y

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| __mod__ (...)

| x.__mod__ (y) <==> x%y

|

| __mul__ (...)

| x.__mul__ (y) <==> x*y

|

| __ne__ (...)

| x.__ne__ (y) <==> x!=y

|

| __neg__ (...)

| x.__neg__ () <==>-X

|

| __nonzero__ (...)

| x.__nonzero__ () <==> x! = 0

|

| __pos__ (...)

| X.__pos__ () <==> +x

|

| __pow__ (...)

| x.__pow__ (y[, z]) <==> pow (x, y[, z])

|

| __radd__ (...)

| x.__radd__ (y) <==> y+x

|

| __rdiv__ (...)

| x.__rdiv__ (y) <==> y/x

|

| __rdivmod__ (...)

| x.__rdivmod__ (y) <==> divmod (y, x)

|

| __repr__ (...)

| x.__repr__ () <==> repr (x)

|

| __rfloordiv__ (...)

| x.__rfloordiv__ (y) <==> y//x

|

| __rmod__ (...)

| x.__rmod__ (y) <==> y%x

|

| __rmul__ (...)

| x.__rmul__ (y) <==> y*x

|

| __rpow__ (...)

| y.__rpow__ (x[, z]) <==> pow (x, y[, z])

|

| __rsub__ (...)

| x.__rsub__ (y) <==> y-x

|

| __rtruediv__ (...)

| x.__rtruediv__ (y) <==> y/x

|

| __setformat__ (...)

| Float.__setformat__ (Typestr, FMT), None

|

|  You probably don ' t want the use of 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 is only

| One of the latter if it appears to match the underlying C reality.

|

| Overrides the automatic determination of c-level floating point type.

| This affects how floats is converted to and from binary strings.

|

| __str__ (...)

| X.__STR__ () <==> str (x)

|

| __sub__ (...)

| x.__sub__ (y) <==> x-y

|

| __truediv__ (...)

| x.__truediv__ (y) <==> x/y

|

| __trunc__ (...)

| Returns the Integral closest to x between 0 and X.

|

| As_integer_ratio (...)

| Float.as_integer_ratio () (int, int)

|

| Returns a pair of integers, whose ratio is exactly equal to the original

| float and with a positive denominator.

| Raises 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 (...)

| Returns self, the complex conjugate of any float.

|

| Fromhex (...)

| Float.fromhex (string), float

|

| Create a floating-point number from a hexadecimal string.

| >>> float.fromhex (' 0x1.ffffp10 ')

| 2047.984375

| >>> float.fromhex (' -0x1p-1074 ')

| -4.9406564584124654e-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 (...)

| Returns 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

|

| ----------------------------------------------------------------------

| Data and other attributes defined here:

|

| __new__ = <built-in method __new__ of type object>

| T.__NEW__ (S, ...)-A new object with type S, a subtype of T

Filter (function, iterable)

Construct a list from those elements of iterable for which function returns TRUE. Iterable May is either a sequence, a container which supports iteration, or an iterator. If iterable is a string or a tuple, the result also have that type; Otherwise it is always a list. If function is a None, the identity function is assumed, which is, and all elements of iterable that is false is removed.

Note that the filter (function, iterable) is equivalent to [item for item ' in Iterable if function (item)] If function was not Non E and [item for item in Iterable if Item] if function is None.

See Itertools.ifilter () and Itertools.ifilterfalse () for iterator versions of this function, including a variation that fi Lters for elements where the function returns FALSE.

English Description:

This function is to convert a string or an integer to a floating-point number. If the parameter x is a string, then only the number string represented by decimal is used, and the number can be preceded by a symbol to indicate a positive or negative amount. If the parameter x is an integer, it can be converted to a floating-point number representation. However, there is a special place for this function, which is to use the infinity or inf to represent an infinite number. For example +inf is positive infinity,-inf is negative infinity.

>>> Float (6)

6.0

>>> float (' 6 ')

6.0

>>> float ()

0.0

>>> float (' +5.778 ')

5.778

>>> float ('-5.778 ')

-5.778

>>> float (' +inf ')

Inf

>>> float ('-inf ')

-inf

>>> float (' nan ')

Nan

>>> class T:

... def __init__ (Self,score):

... self.score = Score

... def __float__ (self):

... return Self.score

...

>>> x=t (10.68)

>>> Float (x)

10.68

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Python built-in function 5-float ()