对于Python，一切事物都是对象，对象基于类创建
Python数据类型
python主要的数据类型主要包括以下几种类型：
(1) 数字型
(2) 字符串
(3) 列表
(4) 元组
(5) 字典
(6) bool型
数字型
一、整数
如： 18、73、84
每一个整数都具备如下功能：
class int(object):
"""
int(x=0) -> int or long
int(x, base=10) -> int or long Convert a number or string to an integer, or return 0 if no arguments
are given. If x is floating point, the conversion truncates towards zero.
If x is outside the integer range, the function returns a long instead. If x is not a number or if base is given, then x must be a string or
Unicode object representing an integer literal in the given base. The
literal can be preceded by '+' or '-' and be surrounded by whitespace.
The base defaults to 10. Valid bases are 0 and 2-36. Base 0 means to
interpret the base from the string as an integer literal.
>>> int('0b100', base=0)
4
"""
def bit_length(self):
""" 返回表示该数字的时占用的最少位数 """
"""
int.bit_length() -> int Number of bits necessary to represent self in binary.
>>> bin(37)
'0b100101'
>>> (37).bit_length()
6
"""
return 0 def conjugate(self, *args, **kwargs): # real signature unknown
""" 返回该复数的共轭复数 """
""" Returns self, the complex conjugate of any int. """
pass def __abs__(self):
""" 返回绝对值 """
""" x.__abs__() <==> abs(x) """
pass def __add__(self, y):
""" x.__add__(y) <==> x+y """
pass def __and__(self, y):
""" x.__and__(y) <==> x&y """
pass def __cmp__(self, y):
""" 比较两个数大小 """
""" x.__cmp__(y) <==> cmp(x,y) """
pass def __coerce__(self, y):
""" 强制生成一个元组 """
""" x.__coerce__(y) <==> coerce(x, y) """
pass def __divmod__(self, y):
""" 相除，得到商和余数组成的元组 """
""" x.__divmod__(y) <==> divmod(x, y) """
pass def __div__(self, y):
""" x.__div__(y) <==> x/y """
pass def __float__(self):
""" 转换为浮点类型 """
""" x.__float__() <==> float(x) """
pass def __floordiv__(self, y):
""" x.__floordiv__(y) <==> x//y """
pass def __format__(self, *args, **kwargs): # real signature unknown
pass def __getattribute__(self, name):
""" x.__getattribute__('name') <==> x.name """
pass def __getnewargs__(self, *args, **kwargs): # real signature unknown
""" 内部调用 __new__方法或创建对象时传入参数使用 """
pass def __hash__(self):
"""如果对象object为哈希表类型，返回对象object的哈希值。哈希值为整数。在字典查找中，哈希值用于快速比较字典的键。两个数值如果相等，则哈希值也相等。"""
""" x.__hash__() <==> hash(x) """
pass def __hex__(self):
""" 返回当前数的 十六进制 表示 """
""" x.__hex__() <==> hex(x) """
pass def __index__(self):
""" 用于切片，数字无意义 """
""" x[y:z] <==> x[y.__index__():z.__index__()] """
pass def __init__(self, x, base=10): # known special case of int.__init__
""" 构造方法，执行 x = 123 或 x = int(10) 时，自动调用，暂时忽略 """
"""
int(x=0) -> int or long
int(x, base=10) -> int or long Convert a number or string to an integer, or return 0 if no arguments
are given. If x is floating point, the conversion truncates towards zero.
If x is outside the integer range, the function returns a long instead. If x is not a number or if base is given, then x must be a string or
Unicode object representing an integer literal in the given base. The
literal can be preceded by '+' or '-' and be surrounded by whitespace.
The base defaults to 10. Valid bases are 0 and 2-36. Base 0 means to
interpret the base from the string as an integer literal.
>>> int('0b100', base=0)
4
# (copied from class doc)
"""
pass def __int__(self):
""" 转换为整数 """
""" x.__int__() <==> int(x) """
pass def __invert__(self):
""" x.__invert__() <==> ~x """
pass def __long__(self):
""" 转换为长整数 """
""" x.__long__() <==> long(x) """
pass def __lshift__(self, y):
""" x.__lshift__(y) <==> x<<y """
pass def __mod__(self, y):
""" x.__mod__(y) <==> x%y """
pass def __mul__(self, y):
""" x.__mul__(y) <==> x*y """
pass def __neg__(self):
""" x.__neg__() <==> -x """
pass @staticmethod # known case of __new__
def __new__(S, *more):
""" T.__new__(S, ...) -> a new object with type S, a subtype of T """
pass def __nonzero__(self):
""" x.__nonzero__() <==> x != 0 """
pass def __oct__(self):
""" 返回改值的 八进制 表示 """
""" x.__oct__() <==> oct(x) """
pass def __or__(self, y):
""" x.__or__(y) <==> x|y """
pass def __pos__(self):
""" x.__pos__() <==> +x """
pass def __pow__(self, y, z=None):
""" 幂，次方 """
""" x.__pow__(y[, z]) <==> pow(x, y[, z]) """
pass def __radd__(self, y):
""" x.__radd__(y) <==> y+x """
pass def __rand__(self, y):
""" x.__rand__(y) <==> y&x """
pass def __rdivmod__(self, y):
""" x.__rdivmod__(y) <==> divmod(y, x) """
pass def __rdiv__(self, y):
""" x.__rdiv__(y) <==> y/x """
pass def __repr__(self):
"""转化为解释器可读取的形式 """
""" x.__repr__() <==> repr(x) """
pass def __str__(self):
"""转换为人阅读的形式，如果没有适于人阅读的解释形式的话，则返回解释器课阅读的形式"""
""" x.__str__() <==> str(x) """
pass def __rfloordiv__(self, y):
""" x.__rfloordiv__(y) <==> y//x """
pass def __rlshift__(self, y):
""" x.__rlshift__(y) <==> y<<x """
pass def __rmod__(self, y):
""" x.__rmod__(y) <==> y%x """
pass def __rmul__(self, y):
""" x.__rmul__(y) <==> y*x """
pass def __ror__(self, y):
""" x.__ror__(y) <==> y|x """
pass def __rpow__(self, x, z=None):
""" y.__rpow__(x[, z]) <==> pow(x, y[, z]) """
pass def __rrshift__(self, y):
""" x.__rrshift__(y) <==> y>>x """
pass def __rshift__(self, y):
""" x.__rshift__(y) <==> x>>y """
pass def __rsub__(self, y):
""" x.__rsub__(y) <==> y-x """
pass def __rtruediv__(self, y):
""" x.__rtruediv__(y) <==> y/x """
pass def __rxor__(self, y):
""" x.__rxor__(y) <==> y^x """
pass def __sub__(self, y):
""" x.__sub__(y) <==> x-y """
pass def __truediv__(self, y):
""" x.__truediv__(y) <==> x/y """
pass def __trunc__(self, *args, **kwargs):
""" 返回数值被截取为整形的值，在整形中无意义 """
pass def __xor__(self, y):
""" x.__xor__(y) <==> x^y """
pass denominator = property(lambda self: object(), lambda self, v: None, lambda self: None) # default
""" 分母 = 1 """
"""the denominator of a rational number in lowest terms""" imag = property(lambda self: object(), lambda self, v: None, lambda self: None) # default
""" 虚数，无意义 """
"""the imaginary part of a complex number""" numerator = property(lambda self: object(), lambda self, v: None, lambda self: None) # default
""" 分子 = 数字大小 """
"""the numerator of a rational number in lowest terms""" real = property(lambda self: object(), lambda self, v: None, lambda self: None) # default
""" 实属，无意义 """
"""the real part of a complex number"""
int
二、长整型
可能如：2147483649、9223372036854775807
每个长整型都具备如下功能：
class long(object):
"""
long(x=0) -> long
long(x, base=10) -> long Convert a number or string to a long integer, or return 0L if no arguments
are given. If x is floating point, the conversion truncates towards zero. If x is not a number or if base is given, then x must be a string or
Unicode object representing an integer literal in the given base. The
literal can be preceded by '+' or '-' and be surrounded by whitespace.
The base defaults to 10. Valid bases are 0 and 2-36. Base 0 means to
interpret the base from the string as an integer literal.
>>> int('0b100', base=0)
4L
"""
def bit_length(self): # real signature unknown; restored from __doc__
"""
long.bit_length() -> int or long Number of bits necessary to represent self in binary.
>>> bin(37L)
'0b100101'
>>> (37L).bit_length()
6
"""
return 0 def conjugate(self, *args, **kwargs): # real signature unknown
""" Returns self, the complex conjugate of any long. """
pass def __abs__(self): # real signature unknown; restored from __doc__
""" x.__abs__() <==> abs(x) """
pass def __add__(self, y): # real signature unknown; restored from __doc__
""" x.__add__(y) <==> x+y """
pass def __and__(self, y): # real signature unknown; restored from __doc__
""" x.__and__(y) <==> x&y """
pass def __cmp__(self, y): # real signature unknown; restored from __doc__
""" x.__cmp__(y) <==> cmp(x,y) """
pass def __coerce__(self, y): # real signature unknown; restored from __doc__
""" x.__coerce__(y) <==> coerce(x, y) """
pass def __divmod__(self, y): # real signature unknown; restored from __doc__
""" x.__divmod__(y) <==> divmod(x, y) """
pass def __div__(self, y): # real signature unknown; restored from __doc__
""" x.__div__(y) <==> x/y """
pass def __float__(self): # real signature unknown; restored from __doc__
""" x.__float__() <==> float(x) """
pass def __floordiv__(self, y): # real signature unknown; restored from __doc__
""" x.__floordiv__(y) <==> x//y """
pass def __format__(self, *args, **kwargs): # real signature unknown
pass def __getattribute__(self, name): # real signature unknown; restored from __doc__
""" x.__getattribute__('name') <==> x.name """
pass def __getnewargs__(self, *args, **kwargs): # real signature unknown
pass def __hash__(self): # real signature unknown; restored from __doc__
""" x.__hash__() <==> hash(x) """
pass def __hex__(self): # real signature unknown; restored from __doc__
""" x.__hex__() <==> hex(x) """
pass def __index__(self): # real signature unknown; restored from __doc__
""" x[y:z] <==> x[y.__index__():z.__index__()] """
pass def __init__(self, x=0): # real signature unknown; restored from __doc__
pass def __int__(self): # real signature unknown; restored from __doc__
""" x.__int__() <==> int(x) """
pass def __invert__(self): # real signature unknown; restored from __doc__
""" x.__invert__() <==> ~x """
pass def __long__(self): # real signature unknown; restored from __doc__
""" x.__long__() <==> long(x) """
pass def __lshift__(self, y): # real signature unknown; restored from __doc__
""" x.__lshift__(y) <==> x<<y """
pass def __mod__(self, y): # real signature unknown; restored from __doc__
""" x.__mod__(y) <==> x%y """
pass def __mul__(self, y): # real signature unknown; restored from __doc__
""" x.__mul__(y) <==> x*y """
pass def __neg__(self): # real signature unknown; restored from __doc__
""" x.__neg__() <==> -x """
pass @staticmethod # known case of __new__
def __new__(S, *more): # real signature unknown; restored from __doc__
""" T.__new__(S, ...) -> a new object with type S, a subtype of T """
pass def __nonzero__(self): # real signature unknown; restored from __doc__
""" x.__nonzero__() <==> x != 0 """
pass def __oct__(self): # real signature unknown; restored from __doc__
""" x.__oct__() <==> oct(x) """
pass def __or__(self, y): # real signature unknown; restored from __doc__
""" x.__or__(y) <==> x|y """
pass def __pos__(self): # real signature unknown; restored from __doc__
""" x.__pos__() <==> +x """
pass def __pow__(self, y, z=None): # real signature unknown; restored from __doc__
""" x.__pow__(y[, z]) <==> pow(x, y[, z]) """
pass def __radd__(self, y): # real signature unknown; restored from __doc__
""" x.__radd__(y) <==> y+x """
pass def __rand__(self, y): # real signature unknown; restored from __doc__
""" x.__rand__(y) <==> y&x """
pass def __rdivmod__(self, y): # real signature unknown; restored from __doc__
""" x.__rdivmod__(y) <==> divmod(y, x) """
pass def __rdiv__(self, y): # real signature unknown; restored from __doc__
""" x.__rdiv__(y) <==> y/x """
pass def __repr__(self): # real signature unknown; restored from __doc__
""" x.__repr__() <==> repr(x) """
pass def __rfloordiv__(self, y): # real signature unknown; restored from __doc__
""" x.__rfloordiv__(y) <==> y//x """
pass def __rlshift__(self, y): # real signature unknown; restored from __doc__
""" x.__rlshift__(y) <==> y<<x """
pass def __rmod__(self, y): # real signature unknown; restored from __doc__
""" x.__rmod__(y) <==> y%x """
pass def __rmul__(self, y): # real signature unknown; restored from __doc__
""" x.__rmul__(y) <==> y*x """
pass def __ror__(self, y): # real signature unknown; restored from __doc__
""" x.__ror__(y) <==> y|x """
pass def __rpow__(self, x, z=None): # real signature unknown; restored from __doc__
""" y.__rpow__(x[, z]) <==> pow(x, y[, z]) """
pass def __rrshift__(self, y): # real signature unknown; restored from __doc__
""" x.__rrshift__(y) <==> y>>x """
pass def __rshift__(self, y): # real signature unknown; restored from __doc__
""" x.__rshift__(y) <==> x>>y """
pass def __rsub__(self, y): # real signature unknown; restored from __doc__
""" x.__rsub__(y) <==> y-x """
pass def __rtruediv__(self, y): # real signature unknown; restored from __doc__
""" x.__rtruediv__(y) <==> y/x """
pass def __rxor__(self, y): # real signature unknown; restored from __doc__
""" x.__rxor__(y) <==> y^x """
pass def __sizeof__(self, *args, **kwargs): # real signature unknown
""" Returns size in memory, in bytes """
pass def __str__(self): # real signature unknown; restored from __doc__
""" x.__str__() <==> str(x) """
pass def __sub__(self, y): # real signature unknown; restored from __doc__
""" x.__sub__(y) <==> x-y """
pass def __truediv__(self, y): # real signature unknown; restored from __doc__
""" x.__truediv__(y) <==> x/y """
pass def __trunc__(self, *args, **kwargs): # real signature unknown
""" Truncating an Integral returns itself. """
pass def __xor__(self, y): # real signature unknown; restored from __doc__
""" x.__xor__(y) <==> x^y """
pass denominator = property(lambda self: object(), lambda self, v: None, lambda self: None) # default
"""the denominator of a rational number in lowest terms""" imag = property(lambda self: object(), lambda self, v: None, lambda self: None) # default
"""the imaginary part of a complex number""" numerator = property(lambda self: object(), lambda self, v: None, lambda self: None) # default
"""the numerator of a rational number in lowest terms""" real = property(lambda self: object(), lambda self, v: None, lambda self: None) # default
"""the real part of a complex number"""
Long
三、浮点型
如：3.14、2.88
每个浮点型都具备如下功能：
class float(object):
"""
float(x) -> floating point number Convert a string or number to a floating point number, if possible.
"""
def as_integer_ratio(self):
""" 获取改值的最简比 """
"""
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)
"""
pass def conjugate(self, *args, **kwargs): # real signature unknown
""" Return self, the complex conjugate of any float. """
pass def fromhex(self, string):
""" 将十六进制字符串转换成浮点型 """
"""
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
"""
return 0.0 def hex(self):
""" 返回当前值的 16 进制表示 """
"""
float.hex() -> string Return a hexadecimal representation of a floating-point number.
>>> (-0.1).hex()
'-0x1.999999999999ap-4'
>>> 3.14159.hex()
'0x1.921f9f01b866ep+1'
"""
return "" def is_integer(self, *args, **kwargs): # real signature unknown
""" Return True if the float is an integer. """
pass def __abs__(self):
""" x.__abs__() <==> abs(x) """
pass def __add__(self, y):
""" x.__add__(y) <==> x+y """
pass def __coerce__(self, y):
""" x.__coerce__(y) <==> coerce(x, y) """
pass def __divmod__(self, y):
""" x.__divmod__(y) <==> divmod(x, y) """
pass def __div__(self, y):
""" x.__div__(y) <==> x/y """
pass def __eq__(self, y):
""" x.__eq__(y) <==> x==y """
pass def __float__(self):
""" x.__float__() <==> float(x) """
pass def __floordiv__(self, y):
""" x.__floordiv__(y) <==> x//y """
pass def __format__(self, format_spec):
"""
float.__format__(format_spec) -> string Formats the float according to format_spec.
"""
return "" def __getattribute__(self, name):
""" x.__getattribute__('name') <==> x.name """
pass def __getformat__(self, typestr):
"""
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.
"""
return "" def __getnewargs__(self, *args, **kwargs): # real signature unknown
pass def __ge__(self, y):
""" x.__ge__(y) <==> x>=y """
pass def __gt__(self, y):
""" x.__gt__(y) <==> x>y """
pass def __hash__(self):
""" x.__hash__() <==> hash(x) """
pass def __init__(self, x):
pass def __int__(self):
""" x.__int__() <==> int(x) """
pass def __le__(self, y):
""" x.__le__(y) <==> x<=y """
pass def __long__(self):
""" x.__long__() <==> long(x) """
pass def __lt__(self, y):
""" x.__lt__(y) <==> x<y """
pass def __mod__(self, y):
""" x.__mod__(y) <==> x%y """
pass def __mul__(self, y):
""" x.__mul__(y) <==> x*y """
pass def __neg__(self):
""" x.__neg__() <==> -x """
pass @staticmethod # known case of __new__
def __new__(S, *more):
""" T.__new__(S, ...) -> a new object with type S, a subtype of T """
pass def __ne__(self, y):
""" x.__ne__(y) <==> x!=y """
pass def __nonzero__(self):
""" x.__nonzero__() <==> x != 0 """
pass def __pos__(self):
""" x.__pos__() <==> +x """
pass def __pow__(self, y, z=None):
""" x.__pow__(y[, z]) <==> pow(x, y[, z]) """
pass def __radd__(self, y):
""" x.__radd__(y) <==> y+x """
pass def __rdivmod__(self, y):
""" x.__rdivmod__(y) <==> divmod(y, x) """
pass def __rdiv__(self, y):
""" x.__rdiv__(y) <==> y/x """
pass def __repr__(self):
""" x.__repr__() <==> repr(x) """
pass def __rfloordiv__(self, y):
""" x.__rfloordiv__(y) <==> y//x """
pass def __rmod__(self, y):
""" x.__rmod__(y) <==> y%x """
pass def __rmul__(self, y):
""" x.__rmul__(y) <==> y*x """
pass def __rpow__(self, x, z=None):
""" y.__rpow__(x[, z]) <==> pow(x, y[, z]) """
pass def __rsub__(self, y):
""" x.__rsub__(y) <==> y-x """
pass def __rtruediv__(self, y):
""" x.__rtruediv__(y) <==> y/x """
pass def __setformat__(self, typestr, fmt):
"""
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.
"""
pass def __str__(self):
""" x.__str__() <==> str(x) """
pass def __sub__(self, y):
""" x.__sub__(y) <==> x-y """
pass def __truediv__(self, y):
""" x.__truediv__(y) <==> x/y """
pass def __trunc__(self, *args, **kwargs): # real signature unknown
""" Return the Integral closest to x between 0 and x. """
pass imag = property(lambda self: object(), lambda self, v: None, lambda self: None) # default
"""the imaginary part of a complex number""" real = property(lambda self: object(), lambda self, v: None, lambda self: None) # default
"""the real part of a complex number"""
float
字符串
如：'gary'、'leon
每个字符串都具备如下功能：
class str(basestring):
"""
str(object='') -> string Return a nice string representation of the object.
If the argument is a string, the return value is the same object.
"""
def capitalize(self):
""" 首字母变大写 """
"""
S.capitalize() -> string Return a copy of the string S with only its first character
capitalized.
"""
return "" def center(self, width, fillchar=None):
""" 内容居中，width：总长度；fillchar：空白处填充内容，默认无 """
"""
S.center(width[, fillchar]) -> string Return S centered in a string of length width. Padding is
done using the specified fill character (default is a space)
"""
return "" def count(self, sub, start=None, end=None):
""" 子序列个数 """
"""
S.count(sub[, start[, end]]) -> int Return the number of non-overlapping occurrences of substring sub in
string S[start:end]. Optional arguments start and end are interpreted
as in slice notation.
"""
return 0 def decode(self, encoding=None, errors=None):
""" 解码 """
"""
S.decode([encoding[,errors]]) -> object Decodes S using the codec registered for encoding. encoding defaults
to the default encoding. errors may be given to set a different error
handling scheme. Default is 'strict' meaning that encoding errors raise
a UnicodeDecodeError. Other possible values are 'ignore' and 'replace'
as well as any other name registered with codecs.register_error that is
able to handle UnicodeDecodeErrors.
"""
return object() def encode(self, encoding=None, errors=None):
""" 编码，针对unicode """
"""
S.encode([encoding[,errors]]) -> object Encodes S using the codec registered for encoding. encoding defaults
to the default encoding. errors may be given to set a different error
handling scheme. Default is 'strict' meaning that encoding errors raise
a UnicodeEncodeError. Other possible values are 'ignore', 'replace' and
'xmlcharrefreplace' as well as any other name registered with
codecs.register_error that is able to handle UnicodeEncodeErrors.
"""
return object() def endswith(self, suffix, start=None, end=None):
""" 是否以 xxx 结束 """
"""
S.endswith(suffix[, start[, end]]) -> bool Return True if S ends with the specified suffix, False otherwise.
With optional start, test S beginning at that position.
With optional end, stop comparing S at that position.
suffix can also be a tuple of strings to try.
"""
return False def expandtabs(self, tabsize=None):
""" 将tab转换成空格，默认一个tab转换成8个空格 """
"""
S.expandtabs([tabsize]) -> string Return a copy of S where all tab characters are expanded using spaces.
If tabsize is not given, a tab size of 8 characters is assumed.
"""
return "" def find(self, sub, start=None, end=None):
""" 寻找子序列位置，如果没找到，返回 -1 """
"""
S.find(sub [,start [,end]]) -> int Return the lowest index in S where substring sub is found,
such that sub is contained within S[start:end]. Optional
arguments start and end are interpreted as in slice notation. Return -1 on failure.
"""
return 0 def format(*args, **kwargs): # known special case of str.format
""" 字符串格式化，动态参数，将函数式编程时细说 """
"""
S.format(*args, **kwargs) -> string Return a formatted version of S, using substitutions from args and kwargs.
The substitutions are identified by braces ('{' and '}').
"""
pass def index(self, sub, start=None, end=None):
""" 子序列位置，如果没找到，报错 """
S.index(sub [,start [,end]]) -> int Like S.find() but raise ValueError when the substring is not found.
"""
return 0 def isalnum(self):
""" 是否是字母和数字 """
"""
S.isalnum() -> bool Return True if all characters in S are alphanumeric
and there is at least one character in S, False otherwise.
"""
return False def isalpha(self):
""" 是否是字母 """
"""
S.isalpha() -> bool Return True if all characters in S are alphabetic
and there is at least one character in S, False otherwise.
"""
return False def isdigit(self):
""" 是否是数字 """
"""
S.isdigit() -> bool Return True if all characters in S are digits
and there is at least one character in S, False otherwise.
"""
return False def islower(self):
""" 是否小写 """
"""
S.islower() -> bool Return True if all cased characters in S are lowercase and there is
at least one cased character in S, False otherwise.
"""
return False def isspace(self):
"""
S.isspace() -> bool Return True if all characters in S are whitespace
and there is at least one character in S, False otherwise.
"""
return False def istitle(self):
"""
S.istitle() -> bool Return True if S is a titlecased string and there is at least one
character in S, i.e. uppercase characters may only follow uncased
characters and lowercase characters only cased ones. Return False
otherwise.
"""
return False def isupper(self):
"""
S.isupper() -> bool Return True if all cased characters in S are uppercase and there is
at least one cased character in S, False otherwise.
"""
return False def join(self, iterable):
""" 连接 """
"""
S.join(iterable) -> string Return a string which is the concatenation of the strings in the
iterable. The separator between elements is S.
"""
return "" def ljust(self, width, fillchar=None):
""" 内容左对齐，右侧填充 """
"""
S.ljust(width[, fillchar]) -> string Return S left-justified in a string of length width. Padding is
done using the specified fill character (default is a space).
"""
return "" def lower(self):
""" 变小写 """
"""
S.lower() -> string Return a copy of the string S converted to lowercase.
"""
return "" def lstrip(self, chars=None):
""" 移除左侧空白 """
"""
S.lstrip([chars]) -> string or unicode Return a copy of the string S with leading whitespace removed.
If chars is given and not None, remove characters in chars instead.
If chars is unicode, S will be converted to unicode before stripping
"""
return "" def partition(self, sep):
""" 分割，前，中，后三部分 """
"""
S.partition(sep) -> (head, sep, tail) Search for the separator sep in S, and return the part before it,
the separator itself, and the part after it. If the separator is not
found, return S and two empty strings.
"""
pass def replace(self, old, new, count=None):
""" 替换 """
"""
S.replace(old, new[, count]) -> string Return a copy of string S with all occurrences of substring
old replaced by new. If the optional argument count is
given, only the first count occurrences are replaced.
"""
return "" def rfind(self, sub, start=None, end=None):
"""
S.rfind(sub [,start [,end]]) -> int Return the highest index in S where substring sub is found,
such that sub is contained within S[start:end]. Optional
arguments start and end are interpreted as in slice notation. Return -1 on failure.
"""
return 0 def rindex(self, sub, start=None, end=None):
"""
S.rindex(sub [,start [,end]]) -> int Like S.rfind() but raise ValueError when the substring is not found.
"""
return 0 def rjust(self, width, fillchar=None):
"""
S.rjust(width[, fillchar]) -> string Return S right-justified in a string of length width. Padding is
done using the specified fill character (default is a space)
"""
return "" def rpartition(self, sep):
"""
S.rpartition(sep) -> (head, sep, tail) Search for the separator sep in S, starting at the end of S, and return
the part before it, the separator itself, and the part after it. If the
separator is not found, return two empty strings and S.
"""
pass def rsplit(self, sep=None, maxsplit=None):
"""
S.rsplit([sep [,maxsplit]]) -> list of strings Return a list of the words in the string S, using sep as the
delimiter string, starting at the end of the string and working
to the front. If maxsplit is given, at most maxsplit splits are
done. If sep is not specified or is None, any whitespace string
is a separator.
"""
return [] def rstrip(self, chars=None):
"""
S.rstrip([chars]) -> string or unicode Return a copy of the string S with trailing whitespace removed.
If chars is given and not None, remove characters in chars instead.
If chars is unicode, S will be converted to unicode before stripping
"""
return "" def split(self, sep=None, maxsplit=None):
""" 分割， maxsplit最多分割几次 """
"""
S.split([sep [,maxsplit]]) -> list of strings Return a list of the words in the string S, using sep as the
delimiter string. If maxsplit is given, at most maxsplit
splits are done. If sep is not specified or is None, any
whitespace string is a separator and empty strings are removed
from the result.
"""
return [] def splitlines(self, keepends=False):
""" 根据换行分割 """
"""
S.splitlines(keepends=False) -> list of strings Return a list of the lines in S, breaking at line boundaries.
Line breaks are not included in the resulting list unless keepends
is given and true.
"""
return [] def startswith(self, prefix, start=None, end=None):
""" 是否起始 """
"""
S.startswith(prefix[, start[, end]]) -> bool Return True if S starts with the specified prefix, False otherwise.
With optional start, test S beginning at that position.
With optional end, stop comparing S at that position.
prefix can also be a tuple of strings to try.
"""
return False def strip(self, chars=None):
""" 移除两段空白 """
"""
S.strip([chars]) -> string or unicode Return a copy of the string S with leading and trailing
whitespace removed.
If chars is given and not None, remove characters in chars instead.
If chars is unicode, S will be converted to unicode before stripping
"""
return "" def swapcase(self):
""" 大写变小写，小写变大写 """
"""
S.swapcase() -> string Return a copy of the string S with uppercase characters
converted to lowercase and vice versa.
"""
return "" def title(self):
"""
S.title() -> string Return a titlecased version of S, i.e. words start with uppercase
characters, all remaining cased characters have lowercase.
"""
return "" def translate(self, table, deletechars=None):
"""
转换，需要先做一个对应表，最后一个表示删除字符集合
intab = "aeiou"
outtab = ""
trantab = maketrans(intab, outtab)
str = "this is string example....wow!!!"
print str.translate(trantab, 'xm')
""" """
S.translate(table [,deletechars]) -> string Return a copy of the string S, where all characters occurring
in the optional argument deletechars are removed, and the
remaining characters have been mapped through the given
translation table, which must be a string of length 256 or None.
If the table argument is None, no translation is applied and
the operation simply removes the characters in deletechars.
"""
return "" def upper(self):
"""
S.upper() -> string Return a copy of the string S converted to uppercase.
"""
return "" def zfill(self, width):
"""方法返回指定长度的字符串，原字符串右对齐，前面填充0。"""
"""
S.zfill(width) -> string Pad a numeric string S with zeros on the left, to fill a field
of the specified width. The string S is never truncated.
"""
return "" def _formatter_field_name_split(self, *args, **kwargs): # real signature unknown
pass def _formatter_parser(self, *args, **kwargs): # real signature unknown
pass def __add__(self, y):
""" x.__add__(y) <==> x+y """
pass def __contains__(self, y):
""" x.__contains__(y) <==> y in x """
pass def __eq__(self, y):
""" x.__eq__(y) <==> x==y """
pass def __format__(self, format_spec):
"""
S.__format__(format_spec) -> string Return a formatted version of S as described by format_spec.
"""
return "" def __getattribute__(self, name):
""" x.__getattribute__('name') <==> x.name """
pass def __getitem__(self, y):
""" x.__getitem__(y) <==> x[y] """
pass def __getnewargs__(self, *args, **kwargs): # real signature unknown
pass def __getslice__(self, i, j):
"""
x.__getslice__(i, j) <==> x[i:j] Use of negative indices is not supported.
"""
pass def __ge__(self, y):
""" x.__ge__(y) <==> x>=y """
pass def __gt__(self, y):
""" x.__gt__(y) <==> x>y """
pass def __hash__(self):
""" x.__hash__() <==> hash(x) """
pass def __init__(self, string=''): # known special case of str.__init__
"""
str(object='') -> string Return a nice string representation of the object.
If the argument is a string, the return value is the same object.
# (copied from class doc)
"""
pass def __len__(self):
""" x.__len__() <==> len(x) """
pass def __le__(self, y):
""" x.__le__(y) <==> x<=y """
pass def __lt__(self, y):
""" x.__lt__(y) <==> x<y """
pass def __mod__(self, y):
""" x.__mod__(y) <==> x%y """
pass def __mul__(self, n):
""" x.__mul__(n) <==> x*n """
pass @staticmethod # known case of __new__
def __new__(S, *more):
""" T.__new__(S, ...) -> a new object with type S, a subtype of T """
pass def __ne__(self, y):
""" x.__ne__(y) <==> x!=y """
pass def __repr__(self):
""" x.__repr__() <==> repr(x) """
pass def __rmod__(self, y):
""" x.__rmod__(y) <==> y%x """
pass def __rmul__(self, n):
""" x.__rmul__(n) <==> n*x """
pass def __sizeof__(self):
""" S.__sizeof__() -> size of S in memory, in bytes """
pass def __str__(self):
""" x.__str__() <==> str(x) """
pass str
str
常用例子:
字符串内建函数
capitalize : 将字符串的首字母大写，其它均小写
- >>> a = 'aBCdEF'
- >>> a.capitalize()
- 'Abcdef'
casefold : 此功能与lower功能类似,将字符串转换为小写
lower : 将所有字符转换为小写
center rjust ljust : 根据显示的长度中间对齐、左对齐、右对齐，不足的部分根据指定内容填充,默认为空格
- >>>> b 'Hello sOrlD'
- >>> b.center(20)
- ' Hello sOrlD '
- >>> b.center(20,'*')
- '****Hello sOrlD*****'
- >>> b.ljust(20,'*')
- 'Hello sOrlD*********'
- >>> b.rjust(20,'*')
- '*********Hello sOrlD'
count : 统计字符串中包含子串的个数
- >>> a = 'aaAAbbBB'
- >>> a.count('a')
- 2
lstrip 、 rstrip、 strip : 去除字符串左边空格 右边空格 两边空格
- >>> a
- ' abc '
- >>> a.strip()
- 'abc'
- >>> a.lstrip()
- 'abc '
- >>> a.rstrip()
- ' abc'
startswith endswith 是否已制定子串开始 是否已制定子串结尾
- >>> a='abc1234def'
- >>> a.startswith('abc')
- True
- >>> a.endswith('def')
- True
translate 用指定的字符串替换,该内置函数在2.x与3.x中使用方法有一定区别
3.x
- >>> a = '12345'
- >>> b = 'abcde'
- >>> source = 'aAAbc123d'
- >>> source.translate(source.maketrans(b,a))
- '1AA231234'
split rsplit 按照指定字符进行分割
- >>> a = '123e456e789'
- >>> a.split('e')
- ['123', '456', '789']
- >>> a.rsplit('e')
- ['123', '456', '789']
splitlines 按照行分隔，返回一个包含各行作为元素的列表
- >>> a = '''''123
- 456
- 789
- '''
- >>> a
- '123\n456\n789\n'
- >>> a.splitlines()
- ['123', '456', '789']
find rfind 分别表示从左边、右边开始搜索指定的字符串子串,返回从0开始的下标值，找不到返回-1
- >>> a
- '123\n456\n789\n'
- >>> a.find('a')
- -1
- >>> a.find('\n')
- 3
- >>> a.rfind('\n')
- 11
index rindex 功能与上面的find类似，只是找不到的时候返回错误
zfill 指定一个宽度，不足的左边补0
- >>> a = 'abcd'
- >>> a.zfill(10)
- '000000abcd'
upper lower 分别表示转换字母为大 、小 写
join 用指定字符串分隔
- >>> a
- 'abcd'
- >>> ' '.join(a)
- 'a b c d'
- >>> '_'.join(a)
- 'a_b_c_d'
replace 替换指定字符串为子串
- >>> a = '123abc123'
- >>> a.replace('abc','ABC')
- '123ABC123'
swapcase 将字符串的大小写反转，大写变小写，小写变大写
- >>> a='abcABC'
- >>> a.swapcase()
- 'ABCabc''
format 格式化字符串，返回格式化后的内容
- >>> s = 'i am {0}, age is {1},sex is {2}'
- >>> s.format('aaaa',12,'F')
- 'i am aaaa, age is 12,sex is F'
- >>> d = 'i am {name},age is {age}, sex is {sex}'
- >>> d.format(name='sss',age=12,sex='F')
- 'i am sss,age is 12, sex is F'
判断属性：
isnum 是否是数字
isalpha 如果 string 至少有一个字符并且所有字符都是字母则返回 True,否则返回 False
isdecimal 如果 string 只包含十进制数字则返回 True 否则返回 False
istitle 是否是标题(标题的每个单词首字母大写),是返回True
isupper 是否都是大写字母
islower 是否都是小写字母
isdigit 如果 string 只包含数字则返回 True 否则返回 False.
isalnum 如果 string 至少有一个字符并且所有字符都是字母或数字则返回 True,否则返回 False
字符串运算符
+ 字符串连接 a + b 输出结果： HelloPython
* 重复输出字符串 a*2 输出结果：HelloHello
[] 通过索引获取字符串中字符 a[1] 输出结果 e
[ : ] 截取字符串中的一部分 a[1:4] 输出结果 ell
in 成员运算符 - 如果字符串中包含给定的字符返回 True H in a 输出结果 1
not in 成员运算符 - 如果字符串中不包含给定的字符返回 True M not in a 输出结果 1
列表
python中的列表是一个具有灵活性的有序集合对象类型，与字符串不同,列表可以包含任何类型的对象、数字、字符串甚至其他列表。
class list(object):
"""
list() -> new empty list
list(iterable) -> new list initialized from iterable's items
"""
def append(self, p_object): # real signature unknown; restored from __doc__
""" L.append(object) -- append object to end """
pass def count(self, value): # real signature unknown; restored from __doc__
""" L.count(value) -> integer -- return number of occurrences of value """
return 0 def extend(self, iterable): # real signature unknown; restored from __doc__
""" L.extend(iterable) -- extend list by appending elements from the iterable """
pass def index(self, value, start=None, stop=None): # real signature unknown; restored from __doc__
"""
L.index(value, [start, [stop]]) -> integer -- return first index of value.
Raises ValueError if the value is not present.
"""
return 0 def insert(self, index, p_object): # real signature unknown; restored from __doc__
""" L.insert(index, object) -- insert object before index """
pass def pop(self, index=None): # real signature unknown; restored from __doc__
"""
L.pop([index]) -> item -- remove and return item at index (default last).
Raises IndexError if list is empty or index is out of range.
"""
pass def remove(self, value): # real signature unknown; restored from __doc__
"""
L.remove(value) -- remove first occurrence of value.
Raises ValueError if the value is not present.
"""
pass def reverse(self): # real signature unknown; restored from __doc__
""" L.reverse() -- reverse *IN PLACE* """
pass def sort(self, cmp=None, key=None, reverse=False): # real signature unknown; restored from __doc__
"""
L.sort(cmp=None, key=None, reverse=False) -- stable sort *IN PLACE*;
cmp(x, y) -> -1, 0, 1
"""
pass def __add__(self, y): # real signature unknown; restored from __doc__
""" x.__add__(y) <==> x+y """
pass def __contains__(self, y): # real signature unknown; restored from __doc__
""" x.__contains__(y) <==> y in x """
pass def __delitem__(self, y): # real signature unknown; restored from __doc__
""" x.__delitem__(y) <==> del x[y] """
pass def __delslice__(self, i, j): # real signature unknown; restored from __doc__
"""
x.__delslice__(i, j) <==> del x[i:j] Use of negative indices is not supported.
"""
pass def __eq__(self, y): # real signature unknown; restored from __doc__
""" x.__eq__(y) <==> x==y """
pass def __getattribute__(self, name): # real signature unknown; restored from __doc__
""" x.__getattribute__('name') <==> x.name """
pass def __getitem__(self, y): # real signature unknown; restored from __doc__
""" x.__getitem__(y) <==> x[y] """
pass def __getslice__(self, i, j): # real signature unknown; restored from __doc__
"""
x.__getslice__(i, j) <==> x[i:j] Use of negative indices is not supported.
"""
pass def __ge__(self, y): # real signature unknown; restored from __doc__
""" x.__ge__(y) <==> x>=y """
pass def __gt__(self, y): # real signature unknown; restored from __doc__
""" x.__gt__(y) <==> x>y """
pass def __iadd__(self, y): # real signature unknown; restored from __doc__
""" x.__iadd__(y) <==> x+=y """
pass def __imul__(self, y): # real signature unknown; restored from __doc__
""" x.__imul__(y) <==> x*=y """
pass def __init__(self, seq=()): # known special case of list.__init__
"""
list() -> new empty list
list(iterable) -> new list initialized from iterable's items
# (copied from class doc)
"""
pass def __iter__(self): # real signature unknown; restored from __doc__
""" x.__iter__() <==> iter(x) """
pass def __len__(self): # real signature unknown; restored from __doc__
""" x.__len__() <==> len(x) """
pass def __le__(self, y): # real signature unknown; restored from __doc__
""" x.__le__(y) <==> x<=y """
pass def __lt__(self, y): # real signature unknown; restored from __doc__
""" x.__lt__(y) <==> x<y """
pass def __mul__(self, n): # real signature unknown; restored from __doc__
""" x.__mul__(n) <==> x*n """
pass @staticmethod # known case of __new__
def __new__(S, *more): # real signature unknown; restored from __doc__
""" T.__new__(S, ...) -> a new object with type S, a subtype of T """
pass def __ne__(self, y): # real signature unknown; restored from __doc__
""" x.__ne__(y) <==> x!=y """
pass def __repr__(self): # real signature unknown; restored from __doc__
""" x.__repr__() <==> repr(x) """
pass def __reversed__(self): # real signature unknown; restored from __doc__
""" L.__reversed__() -- return a reverse iterator over the list """
pass def __rmul__(self, n): # real signature unknown; restored from __doc__
""" x.__rmul__(n) <==> n*x """
pass def __setitem__(self, i, y): # real signature unknown; restored from __doc__
""" x.__setitem__(i, y) <==> x[i]=y """
pass def __setslice__(self, i, j, y): # real signature unknown; restored from __doc__
"""
x.__setslice__(i, j, y) <==> x[i:j]=y Use of negative indices is not supported.
"""
pass def __sizeof__(self): # real signature unknown; restored from __doc__
""" L.__sizeof__() -- size of L in memory, in bytes """
pass __hash__ = None
复制代码
list
- >>> a=[1,2,3,4]
- >>> b=list('1234')
- >>> c=list(range(4))
- >>> a
- [1, 2, 3, 4]
- >>> b
- ['1', '2', '3', '4']
- >>> c
- [0, 1, 2, 3]
列表常用方法
append extend 扩展列表，追加
- >>> a
- [1, 2, 3, 4]
- >>> b
- ['1', '2', '3', '4']
- >>> a.extend(b)
- >>> a
- [1, 2, 3, 4, '1', '2', '3', '4']
- >>> a.append('10')
- >>> a
- [<span style="font-family: Arial, Helvetica, sans-serif;">1, 2, 3, 4, '1', '2', '3', '4'</span>, '10']
clear 清空列表
- >>> a
- [1, 2, 3, 4, '1', '2', '3', '4']
- >>> a.clear()
- >>> a
- []
copy 拷贝列表
- >>> a
- []
- >>> a = b.copy()
- >>> a
- ['1', '2', '3', '4']
count 获取列表中某元素个数
- >>> a
- ['1', '2', '3', '4', '2', '4', '4', '1', '3']
- >>> a.count('2')
- 2
index 获取列表中指定元素数显的第一个的位置下标
- >>> a
- ['1', '2', '3', '4', '2', '4', '4', '1', '3', '10']
- >>> a.index('2')
- 1
insert(index,obj) 在指定位置index插入指定元素obj
- >>> a.insert(2,'99')
- >>> a
- ['1', '2', '99', '3', '4', '2', '4', '4', '1', '3', '10']
pop(index) 将指定位置的元素取出，并从列表中删除
- >>> a
- ['2', '3', '4', '2', '4', '4', '1', '3']
- >>> a.pop(2)
- '4'
- >>> a
- ['2', '3', '2', '4', '4', '1', '3']
remove(value) 将指定的元素删除,,如果列表有多个指定的值,则从下标0开始的第一个元素删除
- >>> a
- ['2', '3', '2', '4', '1', '3']
- >>> a.remove('2')
- >>> a
- ['3', '2', '4', '1', '3']
reverse 列表元素反转
- >>> a
- [1, 2, 3, 4, 5, 6]
- >>> a.reverse()
- >>> a
- [6, 5, 4, 3, 2, 1]
sort 列表元素正序排序,如果列表中所有元素的类型不一样,则报错
- >>> a
- [6, 5, 4, 3, 2, 1]
- >>> a.sort()
- >>> a
- [1, 2, 3, 4, 5, 6]
应用中的列表
1.分片 和字符串的分片类似，通过 [start:end] 来获取列表中的一段元素
- >>> a
- [1, 2, 3, 4, 5, 6]
- >>> a[0:3]
- [1, 2, 3]
2.运算 列表也支持"+" "*"的运算，和字符类似表示列表的合并和重复
- >>> a = [1,2,3]
- >>> b = [4,5,6]
- >>> a+b
- [1, 2, 3, 4, 5, 6]
- >>> a*2
- [1, 2, 3, 1, 2, 3]
3.矩阵 矩阵就是相当于一个多维数组，在列表中嵌套列表
- >>> a
- [[1, 2, 3], [4, 5, 6], [7, 8, 9]]
- >>> a[1][0]
- 4
4.更改值, 直接对指定的下标值修改
- >>> b
- [4, 5, 6]
- >>> b[1]=100
- >>> b
- [4, 100, 6]
5.列表的遍历
- >>> a=[1,2,3,4,5]
- >>> for i in a:
- print(i)
- 1
- 2
- 3
- 4
- 5
字典(dict)
除了列表之外，字典是python中最灵活的数据结构类型。不过不同于列表的是,字典是一个无序的集合，而且字典是通过键值来获取值,而不是通过偏移来获取值。字典的表示形式为 { key：value} 的形式进行保存
class dict(object):
"""
dict() -> new empty dictionary
dict(mapping) -> new dictionary initialized from a mapping object's
(key, value) pairs
dict(iterable) -> new dictionary initialized as if via:
d = {}
for k, v in iterable:
d[k] = v
dict(**kwargs) -> new dictionary initialized with the name=value pairs
in the keyword argument list. For example: dict(one=1, two=2)
""" def clear(self): # real signature unknown; restored from __doc__
""" 清除内容 """
""" D.clear() -> None. Remove all items from D. """
pass def copy(self): # real signature unknown; restored from __doc__
""" 浅拷贝 """
""" D.copy() -> a shallow copy of D """
pass @staticmethod # known case
def fromkeys(S, v=None): # real signature unknown; restored from __doc__
"""
dict.fromkeys(S[,v]) -> New dict with keys from S and values equal to v.
v defaults to None.
"""
pass def get(self, k, d=None): # real signature unknown; restored from __doc__
""" 根据key获取值，d是默认值 """
""" D.get(k[,d]) -> D[k] if k in D, else d. d defaults to None. """
pass def has_key(self, k): # real signature unknown; restored from __doc__
""" 是否有key """
""" D.has_key(k) -> True if D has a key k, else False """
return False def items(self): # real signature unknown; restored from __doc__
""" 所有项的列表形式 """
""" D.items() -> list of D's (key, value) pairs, as 2-tuples """
return [] def iteritems(self): # real signature unknown; restored from __doc__
""" 项可迭代 """
""" D.iteritems() -> an iterator over the (key, value) items of D """
pass def iterkeys(self): # real signature unknown; restored from __doc__
""" key可迭代 """
""" D.iterkeys() -> an iterator over the keys of D """
pass def itervalues(self): # real signature unknown; restored from __doc__
""" value可迭代 """
""" D.itervalues() -> an iterator over the values of D """
pass def keys(self): # real signature unknown; restored from __doc__
""" 所有的key列表 """
""" D.keys() -> list of D's keys """
return [] def pop(self, k, d=None): # real signature unknown; restored from __doc__
""" 获取并在字典中移除 """
"""
D.pop(k[,d]) -> v, remove specified key and return the corresponding value.
If key is not found, d is returned if given, otherwise KeyError is raised
"""
pass def popitem(self): # real signature unknown; restored from __doc__
""" 获取并在字典中移除 """
"""
D.popitem() -> (k, v), remove and return some (key, value) pair as a
2-tuple; but raise KeyError if D is empty.
"""
pass def setdefault(self, k, d=None): # real signature unknown; restored from __doc__
""" 如果key不存在，则创建，如果存在，则返回已存在的值且不修改 """
""" D.setdefault(k[,d]) -> D.get(k,d), also set D[k]=d if k not in D """
pass def update(self, E=None, **F): # known special case of dict.update
""" 更新
{'name':'alex', 'age': 18000}
[('name','sbsbsb'),]
"""
"""
D.update([E, ]**F) -> None. Update D from dict/iterable E and F.
If E present and has a .keys() method, does: for k in E: D[k] = E[k]
If E present and lacks .keys() method, does: for (k, v) in E: D[k] = v
In either case, this is followed by: for k in F: D[k] = F[k]
"""
pass def values(self): # real signature unknown; restored from __doc__
""" 所有的值 """
""" D.values() -> list of D's values """
return [] def viewitems(self): # real signature unknown; restored from __doc__
""" 所有项，只是将内容保存至view对象中 """
""" D.viewitems() -> a set-like object providing a view on D's items """
pass def viewkeys(self): # real signature unknown; restored from __doc__
""" D.viewkeys() -> a set-like object providing a view on D's keys """
pass def viewvalues(self): # real signature unknown; restored from __doc__
""" D.viewvalues() -> an object providing a view on D's values """
pass def __cmp__(self, y): # real signature unknown; restored from __doc__
""" x.__cmp__(y) <==> cmp(x,y) """
pass def __contains__(self, k): # real signature unknown; restored from __doc__
""" D.__contains__(k) -> True if D has a key k, else False """
return False def __delitem__(self, y): # real signature unknown; restored from __doc__
""" x.__delitem__(y) <==> del x[y] """
pass def __eq__(self, y): # real signature unknown; restored from __doc__
""" x.__eq__(y) <==> x==y """
pass def __getattribute__(self, name): # real signature unknown; restored from __doc__
""" x.__getattribute__('name') <==> x.name """
pass def __getitem__(self, y): # real signature unknown; restored from __doc__
""" x.__getitem__(y) <==> x[y] """
pass def __ge__(self, y): # real signature unknown; restored from __doc__
""" x.__ge__(y) <==> x>=y """
pass def __gt__(self, y): # real signature unknown; restored from __doc__
""" x.__gt__(y) <==> x>y """
pass def __init__(self, seq=None, **kwargs): # known special case of dict.__init__
"""
dict() -> new empty dictionary
dict(mapping) -> new dictionary initialized from a mapping object's
(key, value) pairs
dict(iterable) -> new dictionary initialized as if via:
d = {}
for k, v in iterable:
d[k] = v
dict(**kwargs) -> new dictionary initialized with the name=value pairs
in the keyword argument list. For example: dict(one=1, two=2)
# (copied from class doc)
"""
pass def __iter__(self): # real signature unknown; restored from __doc__
""" x.__iter__() <==> iter(x) """
pass def __len__(self): # real signature unknown; restored from __doc__
""" x.__len__() <==> len(x) """
pass def __le__(self, y): # real signature unknown; restored from __doc__
""" x.__le__(y) <==> x<=y """
pass def __lt__(self, y): # real signature unknown; restored from __doc__
""" x.__lt__(y) <==> x<y """
pass @staticmethod # known case of __new__
def __new__(S, *more): # real signature unknown; restored from __doc__
""" T.__new__(S, ...) -> a new object with type S, a subtype of T """
pass def __ne__(self, y): # real signature unknown; restored from __doc__
""" x.__ne__(y) <==> x!=y """
pass def __repr__(self): # real signature unknown; restored from __doc__
""" x.__repr__() <==> repr(x) """
pass def __setitem__(self, i, y): # real signature unknown; restored from __doc__
""" x.__setitem__(i, y) <==> x[i]=y """
pass def __sizeof__(self): # real signature unknown; restored from __doc__
""" D.__sizeof__() -> size of D in memory, in bytes """
pass __hash__ = None
Dict 功能
字典的声明
- >>> a = {'key1':'value1','key2':'value2'}
- >>> a
- {'key1': 'value1', 'key2': 'value2'}
- >>> b=dict(key1='value1',key2='value2')
- >>> b
- {'key1': 'value1', 'key2': 'value2'}
也可以通过两个列表的zip方式来实现
- >>> a=['key1','key2']
- >>> b=['value1','value2']
- >>> d=dict(zip(a,b))
- >>> d
- {'key1': 'value1', 'key2': 'value2'}
字典的常用方法
1 get(key,default) 取值
- >>> d
- {'key1': 'value1', 'key2': 'value2'}
- >>> d['key1'] 直接通过可以获取值,可以不存在则报错
- 'value1'
- >>> d.get('key3','aaa') 通过get可以获取不存在的key,没有返回默认值
- 'aaa'
2 fromkeys(obj,value) 将obj作为可以，value作为默认值生成一个默认字典，obj可以为字典、元组、列表
- >>> aaa = dict.fromkeys((1,2),0) 将元组的值作为key
- >>> aaa
- {1: 0, 2: 0}
- >>> d
- {'key1': 'value1', '1': 'aa', 'key2': 'value2'}
- >>> aaa = dict.fromkeys(d,'123') 将字典d的key作为key
- >>> aaa
- {'key1': '123', '1': '123', 'key2': '123'}
注意：通过fromkey获取生成的字典,有多个key时,每个key的值是一样的,都是指向内存中的同一个地址,所以当修改其中的一个值时,所有的值都会修改
3 clear() 清空字典
4 items() 将字典的key,value作为元组的方式返回成一个列表
- >>> d.items()
- dict_items([('key1', 'value1'), ('1', 'aa'), ('key2', 'value2')])
- >>> for k,v in d.items():
- print(k,v)
- key1 value1
- 1 aa
- key2 value2
4. keys() 将字典的所有key 作为一个列表返回
- >>> d
- {'key1': 'value1', '1': 'aa', 'key2': 'value2'}
- >>> d.keys()
- dict_keys(['key1', '1', 'key2'])
5.pop(k,[,d]) 删除字典的指定键k，并返回k对应的值,如果k不存在,如果指定默认值d则返回d，否则报错
- >>> d
- {'1': 'aa', 'key2': 'value2'}
- >>> d.pop(2,'aaa') 2为key值
- 'aaa'
6.popitem() 删除字典中的(key:value),并将结果以元组的方式返回.如果字典为空将报错KeyError
- >>> d
- {1: '1', 3: '3', 4: '4', 5: '5', 2: '2'}
- >>> d.popitem()
- (3, '3')
- >>> d
- {1: '1', 4: '4', 5: '5', 2: '2'}
由于字典为无序的集合,popitem是也不会按照顺序进行删除
7.values() 与keys方法类似，将字典的结果以列表方式返回
8.update(dict) 字典更新函数， 相当于合并函数，如dic1.update(dic2),将dic2的所有值复制到dic1中，如果有重复键，则将值更新为dic2中健值。
- >>> a1={1:'a',2:'b',3:'c'}
- >>> a2={4:'d',5:'e',2:'f'}
- >>> a1.update(a2)
- >>> a1
- {1: 'a', 2: 'f', 3: 'c', 4: 'd', 5: 'e'}
9. setdefault(k[,d]) 与get类似，只是这个函数用来给字典赋值，如果指定的k在字典中存在则返回字典中的对应值，如果不存在则给字典增加一个K值，value为d
- >>> a1
- {1: 'a', 2: 'f', 3: 'c', 4: 'd', 5: 'e'}
- >>> a1.setdefault(3,'dd')
- 'c'
- >>> a1
- {1: 'a', 2: 'f', 3: 'c', 4: 'd', 5: 'e'}
- >>> a1.setdefault(6,'ddd')
- 'ddd'
- >>> a1
- {1: 'a', 2: 'f', 3: 'c', 4: 'd', 5: 'e', 6: 'ddd'}
Python一路走来 - python基础 数据类型的更多相关文章
-
Python一路走来 Python算法
冒泡排序: 1,2位置左右比较.大的排右边,继续比较2,3 ...... list=[5,7,2,8,12,1] #print(len(list)) for j in range(len(list)) ...
-
小白学 Python（2）：基础数据类型（上）
人生苦短,我选Python 引言 前文传送门 小白学 Python(1):开篇 接触一门新的语言,肯定要先了解它的基础数据类型.啥?你问我为啥要先了解基础数据类型? 为了你的生命安全,还是乖乖听我 B ...
-
小白学 Python（3）：基础数据类型（下）
人生苦短,我选Python 引言 前文传送门 小白学 Python(1):开篇 小白学 Python(2):基础数据类型(上) 前面我们介绍过了数字,本篇我们接着聊另一个常用的基础数据类型:字符串. ...
-
小白学 Python（16）：基础数据类型（函数）（上）
人生苦短,我选Python 前文传送门 小白学 Python(1):开篇 小白学 Python(2):基础数据类型(上) 小白学 Python(3):基础数据类型(下) 小白学 Python(4):变 ...
-
小白学 Python（17）：基础数据类型（函数）（下）
人生苦短,我选Python 前文传送门 小白学 Python(1):开篇 小白学 Python(2):基础数据类型(上) 小白学 Python(3):基础数据类型(下) 小白学 Python(4):变 ...
-
python的学习笔记01_4基础数据类型列表 元组 字典 集合 其他其他（for，enumerate，range)
列表 定义:[]内以逗号分隔,按照索引,存放各种数据类型,每个位置代表一个元素 特性: 1.可存放多个值 2.可修改指定索引位置对应的值,可变 3.按照从左到右的顺序定义列表元素,下标从0开始顺序访问 ...
-
Python 编程核心知识体系-基础|数据类型|控制流（一）
Python知识体系思维导图: 基础知识 数据类型 1.序列 2.字符串 3.列表和元组 4.字典和集合 循环 & 判断
-
Python一路走来 DAY15 Javascript
JavaScript是一门编程语言,浏览器内置了JavaScript语言的解释器,所以在浏览器上按照JavaScript语言的规则编写相应代码之,浏览器可以解释并做出相应的处理. 一 如何编写 ...
-
Python一路走来 RabbitMQ
一:介绍:(induction) Rabbitmq 是一个消息中间件.他的思想就是:接收和发送消息.你可以把它想成一个邮政局.当你把你的邮件发送到邮箱的,首先你需要确认的是:邮政员先生能把你的邮件发送 ...
随机推荐
-
Java变量自增和自减运算符的用法
1.后加加(num++): 先输出运算结果再加加: public static void main(String[] args){ int num=10; int p1=num++; System. ...
-
mysql update操作
update语法 Single-table语法: UPDATE [LOW_PRIORITY] [IGNORE] tbl_name SET col_name1=expr1 [, col_name2=ex ...
-
[转]NHibernate之旅(2)：第一个NHibernate程序
本节内容 开始使用NHibernate 1.获取NHibernate 2.建立数据库表 3.创建C#类库项目 4.设计Domain 4-1.设计持久化类 4-2.编写映射文件 5.数据访问层 5-1. ...
-
Node.js 种子下载器
Node.js 种子下载器 庆祝 2018 国庆,制作了一个 Node.js 的种子下载器.爬取页面,根据页面的链接,破解另外一个网站,下载种子文件.项目比较简单,爬取页面没有使用任何爬虫框架.项目源 ...
-
Java对象序列化全面总结
前言 Java允许我们在内存中创建可复用的Java对象,但一般情况下,这些对象的生命周期不会比JVM的生命周期更长.但在现实应用中,可能要求在JVM停止运行之后能够保存(持久化)指定的对象,并在将来重 ...
-
13.C# 定义类成员
1.定义字段 class MyClass { public int MyInt; } 字段可以用readonly修饰,表示该字段只能在构造函数中赋值,还可以用static表示该字段是静态字段 clas ...
-
【转】sql递归查询问题
原文链接地址http://www.cnblogs.com/sweting/archive/2009/06/08/1498483.html 在工作中遇到一个问题,是需要sql递归查询的.不懂,于是到cs ...
-
【QT学习】信号和槽机制
QT中发射信号使用 emit 来完成. 类要使用信号和槽机制,必须从QObject或者QObject子类继承.必须在类的定义中加上 Q_OBJECT 宏. 信号和槽连接时,参数类型必须相同. 关键字大 ...
-
cadence allegro 布线时添加过孔
1.在放置过孔前先要进行简单的设置. 在菜单栏Setup->Constraints->physical出来的列表里面找到vias 点击出现一个对话框在对话框中选择需要的过孔.(类型比较多可 ...
-
【Android】20.4 录音
分类:C#.Android.VS2015: 创建日期:2016-03-13 一.简介 利用Android提供的MediaRecorder类可直接录制音频. 1.权限要求 录制音频和视频需要下面的权限: ...