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  • python之路第二篇

    python语言介绍

    编译型和解释型

    静态语言和动态语言

    强类型定义语言和弱类型语言

    python数据类型介绍

     python数据类型分:数字、布尔型、字符串、列表、元组、字典

    1、整数

    例如:1,2,33,44等

    整数的功能如下:

      1 class int(object):
      2     """
      3     int(x=0) -> int or long
      4     int(x, base=10) -> int or long
      5     
      6     Convert a number or string to an integer, or return 0 if no arguments
      7     are given.  If x is floating point, the conversion truncates towards zero.
      8     If x is outside the integer range, the function returns a long instead.
      9     
     10     If x is not a number or if base is given, then x must be a string or
     11     Unicode object representing an integer literal in the given base.  The
     12     literal can be preceded by '+' or '-' and be surrounded by whitespace.
     13     The base defaults to 10.  Valid bases are 0 and 2-36.  Base 0 means to
     14     interpret the base from the string as an integer literal.
     15     >>> int('0b100', base=0)
     16     """
     17     def bit_length(self): 
     18         """ 返回表示该数字的时占用的最少位数 """
     19         """
     20         int.bit_length() -> int
     21         
     22         Number of bits necessary to represent self in binary.
     23         >>> bin(37)
     24         '0b100101'
     25         >>> (37).bit_length()
     26         """
     27         return 0
     28 
     29     def conjugate(self, *args, **kwargs): # real signature unknown
     30         """ 返回该复数的共轭复数 """
     31         """ Returns self, the complex conjugate of any int. """
     32         pass
     33 
     34     def __abs__(self):
     35         """ 返回绝对值 """
     36         """ x.__abs__() <==> abs(x) """
     37         pass
     38 
     39     def __add__(self, y):
     40         """ x.__add__(y) <==> x+y """
     41         pass
     42 
     43     def __and__(self, y):
     44         """ x.__and__(y) <==> x&y """
     45         pass
     46 
     47     def __cmp__(self, y): 
     48         """ 比较两个数大小 """
     49         """ x.__cmp__(y) <==> cmp(x,y) """
     50         pass
     51 
     52     def __coerce__(self, y):
     53         """ 强制生成一个元组 """ 
     54         """ x.__coerce__(y) <==> coerce(x, y) """
     55         pass
     56 
     57     def __divmod__(self, y): 
     58         """ 相除,得到商和余数组成的元组 """ 
     59         """ x.__divmod__(y) <==> divmod(x, y) """
     60         pass
     61 
     62     def __div__(self, y): 
     63         """ x.__div__(y) <==> x/y """
     64         pass
     65 
     66     def __float__(self): 
     67         """ 转换为浮点类型 """ 
     68         """ x.__float__() <==> float(x) """
     69         pass
     70 
     71     def __floordiv__(self, y): 
     72         """ x.__floordiv__(y) <==> x//y """
     73         pass
     74 
     75     def __format__(self, *args, **kwargs): # real signature unknown
     76         pass
     77 
     78     def __getattribute__(self, name): 
     79         """ x.__getattribute__('name') <==> x.name """
     80         pass
     81 
     82     def __getnewargs__(self, *args, **kwargs): # real signature unknown
     83         """ 内部调用 __new__方法或创建对象时传入参数使用 """ 
     84         pass
     85 
     86     def __hash__(self): 
     87         """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。"""
     88         """ x.__hash__() <==> hash(x) """
     89         pass
     90 
     91     def __hex__(self): 
     92         """ 返回当前数的 十六进制 表示 """ 
     93         """ x.__hex__() <==> hex(x) """
     94         pass
     95 
     96     def __index__(self): 
     97         """ 用于切片,数字无意义 """
     98         """ x[y:z] <==> x[y.__index__():z.__index__()] """
     99         pass
    100 
    101     def __init__(self, x, base=10): # known special case of int.__init__
    102         """ 构造方法,执行 x = 123 或 x = int(10) 时,自动调用,暂时忽略 """ 
    103         """
    104         int(x=0) -> int or long
    105         int(x, base=10) -> int or long
    106         
    107         Convert a number or string to an integer, or return 0 if no arguments
    108         are given.  If x is floating point, the conversion truncates towards zero.
    109         If x is outside the integer range, the function returns a long instead.
    110         
    111         If x is not a number or if base is given, then x must be a string or
    112         Unicode object representing an integer literal in the given base.  The
    113         literal can be preceded by '+' or '-' and be surrounded by whitespace.
    114         The base defaults to 10.  Valid bases are 0 and 2-36.  Base 0 means to
    115         interpret the base from the string as an integer literal.
    116         >>> int('0b100', base=0)
    117         # (copied from class doc)
    118         """
    119         pass
    120 
    121     def __int__(self): 
    122         """ 转换为整数 """ 
    123         """ x.__int__() <==> int(x) """
    124         pass
    125 
    126     def __invert__(self): 
    127         """ x.__invert__() <==> ~x """
    128         pass
    129 
    130     def __long__(self): 
    131         """ 转换为长整数 """ 
    132         """ x.__long__() <==> long(x) """
    133         pass
    134 
    135     def __lshift__(self, y): 
    136         """ x.__lshift__(y) <==> x<<y """
    137         pass
    138 
    139     def __mod__(self, y): 
    140         """ x.__mod__(y) <==> x%y """
    141         pass
    142 
    143     def __mul__(self, y): 
    144         """ x.__mul__(y) <==> x*y """
    145         pass
    146 
    147     def __neg__(self): 
    148         """ x.__neg__() <==> -x """
    149         pass
    150 
    151     @staticmethod # known case of __new__
    152     def __new__(S, *more): 
    153         """ T.__new__(S, ...) -> a new object with type S, a subtype of T """
    154         pass
    155 
    156     def __nonzero__(self): 
    157         """ x.__nonzero__() <==> x != 0 """
    158         pass
    159 
    160     def __oct__(self): 
    161         """ 返回改值的 八进制 表示 """ 
    162         """ x.__oct__() <==> oct(x) """
    163         pass
    164 
    165     def __or__(self, y): 
    166         """ x.__or__(y) <==> x|y """
    167         pass
    168 
    169     def __pos__(self): 
    170         """ x.__pos__() <==> +x """
    171         pass
    172 
    173     def __pow__(self, y, z=None): 
    174         """ 幂,次方 """ 
    175         """ x.__pow__(y[, z]) <==> pow(x, y[, z]) """
    176         pass
    177 
    178     def __radd__(self, y): 
    179         """ x.__radd__(y) <==> y+x """
    180         pass
    181 
    182     def __rand__(self, y): 
    183         """ x.__rand__(y) <==> y&x """
    184         pass
    185 
    186     def __rdivmod__(self, y): 
    187         """ x.__rdivmod__(y) <==> divmod(y, x) """
    188         pass
    189 
    190     def __rdiv__(self, y): 
    191         """ x.__rdiv__(y) <==> y/x """
    192         pass
    193 
    194     def __repr__(self): 
    195         """转化为解释器可读取的形式 """
    196         """ x.__repr__() <==> repr(x) """
    197         pass
    198 
    199     def __str__(self): 
    200         """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"""
    201         """ x.__str__() <==> str(x) """
    202         pass
    203 
    204     def __rfloordiv__(self, y): 
    205         """ x.__rfloordiv__(y) <==> y//x """
    206         pass
    207 
    208     def __rlshift__(self, y): 
    209         """ x.__rlshift__(y) <==> y<<x """
    210         pass
    211 
    212     def __rmod__(self, y): 
    213         """ x.__rmod__(y) <==> y%x """
    214         pass
    215 
    216     def __rmul__(self, y): 
    217         """ x.__rmul__(y) <==> y*x """
    218         pass
    219 
    220     def __ror__(self, y): 
    221         """ x.__ror__(y) <==> y|x """
    222         pass
    223 
    224     def __rpow__(self, x, z=None): 
    225         """ y.__rpow__(x[, z]) <==> pow(x, y[, z]) """
    226         pass
    227 
    228     def __rrshift__(self, y): 
    229         """ x.__rrshift__(y) <==> y>>x """
    230         pass
    231 
    232     def __rshift__(self, y): 
    233         """ x.__rshift__(y) <==> x>>y """
    234         pass
    235 
    236     def __rsub__(self, y): 
    237         """ x.__rsub__(y) <==> y-x """
    238         pass
    239 
    240     def __rtruediv__(self, y): 
    241         """ x.__rtruediv__(y) <==> y/x """
    242         pass
    243 
    244     def __rxor__(self, y): 
    245         """ x.__rxor__(y) <==> y^x """
    246         pass
    247 
    248     def __sub__(self, y): 
    249         """ x.__sub__(y) <==> x-y """
    250         pass
    251 
    252     def __truediv__(self, y): 
    253         """ x.__truediv__(y) <==> x/y """
    254         pass
    255 
    256     def __trunc__(self, *args, **kwargs): 
    257         """ 返回数值被截取为整形的值,在整形中无意义 """
    258         pass
    259 
    260     def __xor__(self, y): 
    261         """ x.__xor__(y) <==> x^y """
    262         pass
    263 
    264     denominator = property(lambda self: object(), lambda self, v: None, lambda self: None)  # default
    265     """ 分母 = 1 """
    266     """the denominator of a rational number in lowest terms"""
    267 
    268     imag = property(lambda self: object(), lambda self, v: None, lambda self: None)  # default
    269     """ 虚数,无意义 """
    270     """the imaginary part of a complex number"""
    271 
    272     numerator = property(lambda self: object(), lambda self, v: None, lambda self: None)  # default
    273     """ 分子 = 数字大小 """
    274     """the numerator of a rational number in lowest terms"""
    275 
    276     real = property(lambda self: object(), lambda self, v: None, lambda self: None)  # default
    277     """ 实属,无意义 """
    278     """the real part of a complex number"""
    int

    2、长整型

    例如:21474836938、9223372036854863086

    每个长整型都具备如下功能:

      1 class long(object):
      2     """
      3     long(x=0) -> long
      4     long(x, base=10) -> long
      5     
      6     Convert a number or string to a long integer, or return 0L if no arguments
      7     are given.  If x is floating point, the conversion truncates towards zero.
      8     
      9     If x is not a number or if base is given, then x must be a string or
     10     Unicode object representing an integer literal in the given base.  The
     11     literal can be preceded by '+' or '-' and be surrounded by whitespace.
     12     The base defaults to 10.  Valid bases are 0 and 2-36.  Base 0 means to
     13     interpret the base from the string as an integer literal.
     14     >>> int('0b100', base=0)
     15     4L
     16     """
     17     def bit_length(self): # real signature unknown; restored from __doc__
     18         """
     19         long.bit_length() -> int or long
     20         
     21         Number of bits necessary to represent self in binary.
     22         >>> bin(37L)
     23         '0b100101'
     24         >>> (37L).bit_length()
     25         """
     26         return 0
     27 
     28     def conjugate(self, *args, **kwargs): # real signature unknown
     29         """ Returns self, the complex conjugate of any long. """
     30         pass
     31 
     32     def __abs__(self): # real signature unknown; restored from __doc__
     33         """ x.__abs__() <==> abs(x) """
     34         pass
     35 
     36     def __add__(self, y): # real signature unknown; restored from __doc__
     37         """ x.__add__(y) <==> x+y """
     38         pass
     39 
     40     def __and__(self, y): # real signature unknown; restored from __doc__
     41         """ x.__and__(y) <==> x&y """
     42         pass
     43 
     44     def __cmp__(self, y): # real signature unknown; restored from __doc__
     45         """ x.__cmp__(y) <==> cmp(x,y) """
     46         pass
     47 
     48     def __coerce__(self, y): # real signature unknown; restored from __doc__
     49         """ x.__coerce__(y) <==> coerce(x, y) """
     50         pass
     51 
     52     def __divmod__(self, y): # real signature unknown; restored from __doc__
     53         """ x.__divmod__(y) <==> divmod(x, y) """
     54         pass
     55 
     56     def __div__(self, y): # real signature unknown; restored from __doc__
     57         """ x.__div__(y) <==> x/y """
     58         pass
     59 
     60     def __float__(self): # real signature unknown; restored from __doc__
     61         """ x.__float__() <==> float(x) """
     62         pass
     63 
     64     def __floordiv__(self, y): # real signature unknown; restored from __doc__
     65         """ x.__floordiv__(y) <==> x//y """
     66         pass
     67 
     68     def __format__(self, *args, **kwargs): # real signature unknown
     69         pass
     70 
     71     def __getattribute__(self, name): # real signature unknown; restored from __doc__
     72         """ x.__getattribute__('name') <==> x.name """
     73         pass
     74 
     75     def __getnewargs__(self, *args, **kwargs): # real signature unknown
     76         pass
     77 
     78     def __hash__(self): # real signature unknown; restored from __doc__
     79         """ x.__hash__() <==> hash(x) """
     80         pass
     81 
     82     def __hex__(self): # real signature unknown; restored from __doc__
     83         """ x.__hex__() <==> hex(x) """
     84         pass
     85 
     86     def __index__(self): # real signature unknown; restored from __doc__
     87         """ x[y:z] <==> x[y.__index__():z.__index__()] """
     88         pass
     89 
     90     def __init__(self, x=0): # real signature unknown; restored from __doc__
     91         pass
     92 
     93     def __int__(self): # real signature unknown; restored from __doc__
     94         """ x.__int__() <==> int(x) """
     95         pass
     96 
     97     def __invert__(self): # real signature unknown; restored from __doc__
     98         """ x.__invert__() <==> ~x """
     99         pass
    100 
    101     def __long__(self): # real signature unknown; restored from __doc__
    102         """ x.__long__() <==> long(x) """
    103         pass
    104 
    105     def __lshift__(self, y): # real signature unknown; restored from __doc__
    106         """ x.__lshift__(y) <==> x<<y """
    107         pass
    108 
    109     def __mod__(self, y): # real signature unknown; restored from __doc__
    110         """ x.__mod__(y) <==> x%y """
    111         pass
    112 
    113     def __mul__(self, y): # real signature unknown; restored from __doc__
    114         """ x.__mul__(y) <==> x*y """
    115         pass
    116 
    117     def __neg__(self): # real signature unknown; restored from __doc__
    118         """ x.__neg__() <==> -x """
    119         pass
    120 
    121     @staticmethod # known case of __new__
    122     def __new__(S, *more): # real signature unknown; restored from __doc__
    123         """ T.__new__(S, ...) -> a new object with type S, a subtype of T """
    124         pass
    125 
    126     def __nonzero__(self): # real signature unknown; restored from __doc__
    127         """ x.__nonzero__() <==> x != 0 """
    128         pass
    129 
    130     def __oct__(self): # real signature unknown; restored from __doc__
    131         """ x.__oct__() <==> oct(x) """
    132         pass
    133 
    134     def __or__(self, y): # real signature unknown; restored from __doc__
    135         """ x.__or__(y) <==> x|y """
    136         pass
    137 
    138     def __pos__(self): # real signature unknown; restored from __doc__
    139         """ x.__pos__() <==> +x """
    140         pass
    141 
    142     def __pow__(self, y, z=None): # real signature unknown; restored from __doc__
    143         """ x.__pow__(y[, z]) <==> pow(x, y[, z]) """
    144         pass
    145 
    146     def __radd__(self, y): # real signature unknown; restored from __doc__
    147         """ x.__radd__(y) <==> y+x """
    148         pass
    149 
    150     def __rand__(self, y): # real signature unknown; restored from __doc__
    151         """ x.__rand__(y) <==> y&x """
    152         pass
    153 
    154     def __rdivmod__(self, y): # real signature unknown; restored from __doc__
    155         """ x.__rdivmod__(y) <==> divmod(y, x) """
    156         pass
    157 
    158     def __rdiv__(self, y): # real signature unknown; restored from __doc__
    159         """ x.__rdiv__(y) <==> y/x """
    160         pass
    161 
    162     def __repr__(self): # real signature unknown; restored from __doc__
    163         """ x.__repr__() <==> repr(x) """
    164         pass
    165 
    166     def __rfloordiv__(self, y): # real signature unknown; restored from __doc__
    167         """ x.__rfloordiv__(y) <==> y//x """
    168         pass
    169 
    170     def __rlshift__(self, y): # real signature unknown; restored from __doc__
    171         """ x.__rlshift__(y) <==> y<<x """
    172         pass
    173 
    174     def __rmod__(self, y): # real signature unknown; restored from __doc__
    175         """ x.__rmod__(y) <==> y%x """
    176         pass
    177 
    178     def __rmul__(self, y): # real signature unknown; restored from __doc__
    179         """ x.__rmul__(y) <==> y*x """
    180         pass
    181 
    182     def __ror__(self, y): # real signature unknown; restored from __doc__
    183         """ x.__ror__(y) <==> y|x """
    184         pass
    185 
    186     def __rpow__(self, x, z=None): # real signature unknown; restored from __doc__
    187         """ y.__rpow__(x[, z]) <==> pow(x, y[, z]) """
    188         pass
    189 
    190     def __rrshift__(self, y): # real signature unknown; restored from __doc__
    191         """ x.__rrshift__(y) <==> y>>x """
    192         pass
    193 
    194     def __rshift__(self, y): # real signature unknown; restored from __doc__
    195         """ x.__rshift__(y) <==> x>>y """
    196         pass
    197 
    198     def __rsub__(self, y): # real signature unknown; restored from __doc__
    199         """ x.__rsub__(y) <==> y-x """
    200         pass
    201 
    202     def __rtruediv__(self, y): # real signature unknown; restored from __doc__
    203         """ x.__rtruediv__(y) <==> y/x """
    204         pass
    205 
    206     def __rxor__(self, y): # real signature unknown; restored from __doc__
    207         """ x.__rxor__(y) <==> y^x """
    208         pass
    209 
    210     def __sizeof__(self, *args, **kwargs): # real signature unknown
    211         """ Returns size in memory, in bytes """
    212         pass
    213 
    214     def __str__(self): # real signature unknown; restored from __doc__
    215         """ x.__str__() <==> str(x) """
    216         pass
    217 
    218     def __sub__(self, y): # real signature unknown; restored from __doc__
    219         """ x.__sub__(y) <==> x-y """
    220         pass
    221 
    222     def __truediv__(self, y): # real signature unknown; restored from __doc__
    223         """ x.__truediv__(y) <==> x/y """
    224         pass
    225 
    226     def __trunc__(self, *args, **kwargs): # real signature unknown
    227         """ Truncating an Integral returns itself. """
    228         pass
    229 
    230     def __xor__(self, y): # real signature unknown; restored from __doc__
    231         """ x.__xor__(y) <==> x^y """
    232         pass
    233 
    234     denominator = property(lambda self: object(), lambda self, v: None, lambda self: None)  # default
    235     """the denominator of a rational number in lowest terms"""
    236 
    237     imag = property(lambda self: object(), lambda self, v: None, lambda self: None)  # default
    238     """the imaginary part of a complex number"""
    239 
    240     numerator = property(lambda self: object(), lambda self, v: None, lambda self: None)  # default
    241     """the numerator of a rational number in lowest terms"""
    242 
    243     real = property(lambda self: object(), lambda self, v: None, lambda self: None)  # default
    244     """the real part of a complex number"""
    long

    3、浮点型

    如:3.14、6.88

    每个浮点型都具备如下功能:

      1 class float(object):
      2     """
      3     float(x) -> floating point number
      4     
      5     Convert a string or number to a floating point number, if possible.
      6     """
      7     def as_integer_ratio(self):   
      8         """ 获取改值的最简比 """
      9         """
     10         float.as_integer_ratio() -> (int, int)
     11 
     12         Return a pair of integers, whose ratio is exactly equal to the original
     13         float and with a positive denominator.
     14         Raise OverflowError on infinities and a ValueError on NaNs.
     15 
     16         >>> (10.0).as_integer_ratio()
     17         (10, 1)
     18         >>> (0.0).as_integer_ratio()
     19         (0, 1)
     20         >>> (-.25).as_integer_ratio()
     21         (-1, 4)
     22         """
     23         pass
     24 
     25     def conjugate(self, *args, **kwargs): # real signature unknown
     26         """ Return self, the complex conjugate of any float. """
     27         pass
     28 
     29     def fromhex(self, string):   
     30         """ 将十六进制字符串转换成浮点型 """
     31         """
     32         float.fromhex(string) -> float
     33         
     34         Create a floating-point number from a hexadecimal string.
     35         >>> float.fromhex('0x1.ffffp10')
     36         2047.984375
     37         >>> float.fromhex('-0x1p-1074')
     38         -4.9406564584124654e-324
     39         """
     40         return 0.0
     41 
     42     def hex(self):   
     43         """ 返回当前值的 16 进制表示 """
     44         """
     45         float.hex() -> string
     46         
     47         Return a hexadecimal representation of a floating-point number.
     48         >>> (-0.1).hex()
     49         '-0x1.999999999999ap-4'
     50         >>> 3.14159.hex()
     51         '0x1.921f9f01b866ep+1'
     52         """
     53         return ""
     54 
     55     def is_integer(self, *args, **kwargs): # real signature unknown
     56         """ Return True if the float is an integer. """
     57         pass
     58 
     59     def __abs__(self):   
     60         """ x.__abs__() <==> abs(x) """
     61         pass
     62 
     63     def __add__(self, y):   
     64         """ x.__add__(y) <==> x+y """
     65         pass
     66 
     67     def __coerce__(self, y):   
     68         """ x.__coerce__(y) <==> coerce(x, y) """
     69         pass
     70 
     71     def __divmod__(self, y):   
     72         """ x.__divmod__(y) <==> divmod(x, y) """
     73         pass
     74 
     75     def __div__(self, y):   
     76         """ x.__div__(y) <==> x/y """
     77         pass
     78 
     79     def __eq__(self, y):   
     80         """ x.__eq__(y) <==> x==y """
     81         pass
     82 
     83     def __float__(self):   
     84         """ x.__float__() <==> float(x) """
     85         pass
     86 
     87     def __floordiv__(self, y):   
     88         """ x.__floordiv__(y) <==> x//y """
     89         pass
     90 
     91     def __format__(self, format_spec):   
     92         """
     93         float.__format__(format_spec) -> string
     94         
     95         Formats the float according to format_spec.
     96         """
     97         return ""
     98 
     99     def __getattribute__(self, name):   
    100         """ x.__getattribute__('name') <==> x.name """
    101         pass
    102 
    103     def __getformat__(self, typestr):   
    104         """
    105         float.__getformat__(typestr) -> string
    106         
    107         You probably don't want to use this function.  It exists mainly to be
    108         used in Python's test suite.
    109         
    110         typestr must be 'double' or 'float'.  This function returns whichever of
    111         'unknown', 'IEEE, big-endian' or 'IEEE, little-endian' best describes the
    112         format of floating point numbers used by the C type named by typestr.
    113         """
    114         return ""
    115 
    116     def __getnewargs__(self, *args, **kwargs): # real signature unknown
    117         pass
    118 
    119     def __ge__(self, y):   
    120         """ x.__ge__(y) <==> x>=y """
    121         pass
    122 
    123     def __gt__(self, y):   
    124         """ x.__gt__(y) <==> x>y """
    125         pass
    126 
    127     def __hash__(self):   
    128         """ x.__hash__() <==> hash(x) """
    129         pass
    130 
    131     def __init__(self, x):   
    132         pass
    133 
    134     def __int__(self):   
    135         """ x.__int__() <==> int(x) """
    136         pass
    137 
    138     def __le__(self, y):   
    139         """ x.__le__(y) <==> x<=y """
    140         pass
    141 
    142     def __long__(self):   
    143         """ x.__long__() <==> long(x) """
    144         pass
    145 
    146     def __lt__(self, y):   
    147         """ x.__lt__(y) <==> x<y """
    148         pass
    149 
    150     def __mod__(self, y):   
    151         """ x.__mod__(y) <==> x%y """
    152         pass
    153 
    154     def __mul__(self, y):   
    155         """ x.__mul__(y) <==> x*y """
    156         pass
    157 
    158     def __neg__(self):   
    159         """ x.__neg__() <==> -x """
    160         pass
    161 
    162     @staticmethod # known case of __new__
    163     def __new__(S, *more):   
    164         """ T.__new__(S, ...) -> a new object with type S, a subtype of T """
    165         pass
    166 
    167     def __ne__(self, y):   
    168         """ x.__ne__(y) <==> x!=y """
    169         pass
    170 
    171     def __nonzero__(self):   
    172         """ x.__nonzero__() <==> x != 0 """
    173         pass
    174 
    175     def __pos__(self):   
    176         """ x.__pos__() <==> +x """
    177         pass
    178 
    179     def __pow__(self, y, z=None):   
    180         """ x.__pow__(y[, z]) <==> pow(x, y[, z]) """
    181         pass
    182 
    183     def __radd__(self, y):   
    184         """ x.__radd__(y) <==> y+x """
    185         pass
    186 
    187     def __rdivmod__(self, y):   
    188         """ x.__rdivmod__(y) <==> divmod(y, x) """
    189         pass
    190 
    191     def __rdiv__(self, y):   
    192         """ x.__rdiv__(y) <==> y/x """
    193         pass
    194 
    195     def __repr__(self):   
    196         """ x.__repr__() <==> repr(x) """
    197         pass
    198 
    199     def __rfloordiv__(self, y):   
    200         """ x.__rfloordiv__(y) <==> y//x """
    201         pass
    202 
    203     def __rmod__(self, y):   
    204         """ x.__rmod__(y) <==> y%x """
    205         pass
    206 
    207     def __rmul__(self, y):   
    208         """ x.__rmul__(y) <==> y*x """
    209         pass
    210 
    211     def __rpow__(self, x, z=None):   
    212         """ y.__rpow__(x[, z]) <==> pow(x, y[, z]) """
    213         pass
    214 
    215     def __rsub__(self, y):   
    216         """ x.__rsub__(y) <==> y-x """
    217         pass
    218 
    219     def __rtruediv__(self, y):   
    220         """ x.__rtruediv__(y) <==> y/x """
    221         pass
    222 
    223     def __setformat__(self, typestr, fmt):   
    224         """
    225         float.__setformat__(typestr, fmt) -> None
    226         
    227         You probably don't want to use this function.  It exists mainly to be
    228         used in Python's test suite.
    229         
    230         typestr must be 'double' or 'float'.  fmt must be one of 'unknown',
    231         'IEEE, big-endian' or 'IEEE, little-endian', and in addition can only be
    232         one of the latter two if it appears to match the underlying C reality.
    233         
    234         Override the automatic determination of C-level floating point type.
    235         This affects how floats are converted to and from binary strings.
    236         """
    237         pass
    238 
    239     def __str__(self):   
    240         """ x.__str__() <==> str(x) """
    241         pass
    242 
    243     def __sub__(self, y):   
    244         """ x.__sub__(y) <==> x-y """
    245         pass
    246 
    247     def __truediv__(self, y):   
    248         """ x.__truediv__(y) <==> x/y """
    249         pass
    250 
    251     def __trunc__(self, *args, **kwargs): # real signature unknown
    252         """ Return the Integral closest to x between 0 and x. """
    253         pass
    254 
    255     imag = property(lambda self: object(), lambda self, v: None, lambda self: None)  # default
    256     """the imaginary part of a complex number"""
    257 
    258     real = property(lambda self: object(), lambda self, v: None, lambda self: None)  # default
    259     """the real part of a complex number"""
    260 
    261 float
    262 
    263 float
    float

    4、字符串

    如:'jerry'、'good'

    每个字符串都具备如下功能:

      1 class str(basestring):
      2     """
      3     str(object='') -> string
      4     
      5     Return a nice string representation of the object.
      6     If the argument is a string, the return value is the same object.
      7     """
      8     def capitalize(self):  
      9         """ 首字母变大写 """
     10         """
     11         S.capitalize() -> string
     12         
     13         Return a copy of the string S with only its first character
     14         capitalized.
     15         """
     16         return ""
     17 
     18     def center(self, width, fillchar=None):  
     19         """ 内容居中,width:总长度;fillchar:空白处填充内容,默认无 """
     20         """
     21         S.center(width[, fillchar]) -> string
     22         
     23         Return S centered in a string of length width. Padding is
     24         done using the specified fill character (default is a space)
     25         """
     26         return ""
     27 
     28     def count(self, sub, start=None, end=None):  
     29         """ 子序列个数 """
     30         """
     31         S.count(sub[, start[, end]]) -> int
     32         
     33         Return the number of non-overlapping occurrences of substring sub in
     34         string S[start:end].  Optional arguments start and end are interpreted
     35         as in slice notation.
     36         """
     37         return 0
     38 
     39     def decode(self, encoding=None, errors=None):  
     40         """ 解码 """
     41         """
     42         S.decode([encoding[,errors]]) -> object
     43         
     44         Decodes S using the codec registered for encoding. encoding defaults
     45         to the default encoding. errors may be given to set a different error
     46         handling scheme. Default is 'strict' meaning that encoding errors raise
     47         a UnicodeDecodeError. Other possible values are 'ignore' and 'replace'
     48         as well as any other name registered with codecs.register_error that is
     49         able to handle UnicodeDecodeErrors.
     50         """
     51         return object()
     52 
     53     def encode(self, encoding=None, errors=None):  
     54         """ 编码,针对unicode """
     55         """
     56         S.encode([encoding[,errors]]) -> object
     57         
     58         Encodes S using the codec registered for encoding. encoding defaults
     59         to the default encoding. errors may be given to set a different error
     60         handling scheme. Default is 'strict' meaning that encoding errors raise
     61         a UnicodeEncodeError. Other possible values are 'ignore', 'replace' and
     62         'xmlcharrefreplace' as well as any other name registered with
     63         codecs.register_error that is able to handle UnicodeEncodeErrors.
     64         """
     65         return object()
     66 
     67     def endswith(self, suffix, start=None, end=None):  
     68         """ 是否以 xxx 结束 """
     69         """
     70         S.endswith(suffix[, start[, end]]) -> bool
     71         
     72         Return True if S ends with the specified suffix, False otherwise.
     73         With optional start, test S beginning at that position.
     74         With optional end, stop comparing S at that position.
     75         suffix can also be a tuple of strings to try.
     76         """
     77         return False
     78 
     79     def expandtabs(self, tabsize=None):  
     80         """ 将tab转换成空格,默认一个tab转换成8个空格 """
     81         """
     82         S.expandtabs([tabsize]) -> string
     83         
     84         Return a copy of S where all tab characters are expanded using spaces.
     85         If tabsize is not given, a tab size of 8 characters is assumed.
     86         """
     87         return ""
     88 
     89     def find(self, sub, start=None, end=None):  
     90         """ 寻找子序列位置,如果没找到,则异常 """
     91         """
     92         S.find(sub [,start [,end]]) -> int
     93         
     94         Return the lowest index in S where substring sub is found,
     95         such that sub is contained within S[start:end].  Optional
     96         arguments start and end are interpreted as in slice notation.
     97         
     98         Return -1 on failure.
     99         """
    100         return 0
    101 
    102     def format(*args, **kwargs): # known special case of str.format
    103         """ 字符串格式化,动态参数,将函数式编程时细说 """
    104         """
    105         S.format(*args, **kwargs) -> string
    106         
    107         Return a formatted version of S, using substitutions from args and kwargs.
    108         The substitutions are identified by braces ('{' and '}').
    109         """
    110         pass
    111 
    112     def index(self, sub, start=None, end=None):  
    113         """ 子序列位置,如果没找到,则返回-1  """
    114         S.index(sub [,start [,end]]) -> int
    115         
    116         Like S.find() but raise ValueError when the substring is not found.
    117         """
    118         return 0
    119 
    120     def isalnum(self):  
    121         """ 是否是字母和数字 """
    122         """
    123         S.isalnum() -> bool
    124         
    125         Return True if all characters in S are alphanumeric
    126         and there is at least one character in S, False otherwise.
    127         """
    128         return False
    129 
    130     def isalpha(self):  
    131         """ 是否是字母 """
    132         """
    133         S.isalpha() -> bool
    134         
    135         Return True if all characters in S are alphabetic
    136         and there is at least one character in S, False otherwise.
    137         """
    138         return False
    139 
    140     def isdigit(self):  
    141         """ 是否是数字 """
    142         """
    143         S.isdigit() -> bool
    144         
    145         Return True if all characters in S are digits
    146         and there is at least one character in S, False otherwise.
    147         """
    148         return False
    149 
    150     def islower(self):  
    151         """ 是否小写 """
    152         """
    153         S.islower() -> bool
    154         
    155         Return True if all cased characters in S are lowercase and there is
    156         at least one cased character in S, False otherwise.
    157         """
    158         return False
    159 
    160     def isspace(self):  
    161         """
    162         S.isspace() -> bool
    163         
    164         Return True if all characters in S are whitespace
    165         and there is at least one character in S, False otherwise.
    166         """
    167         return False
    168 
    169     def istitle(self):  
    170         """
    171         S.istitle() -> bool
    172         
    173         Return True if S is a titlecased string and there is at least one
    174         character in S, i.e. uppercase characters may only follow uncased
    175         characters and lowercase characters only cased ones. Return False
    176         otherwise.
    177         """
    178         return False
    179 
    180     def isupper(self):  
    181         """
    182         S.isupper() -> bool
    183         
    184         Return True if all cased characters in S are uppercase and there is
    185         at least one cased character in S, False otherwise.
    186         """
    187         return False
    188 
    189     def join(self, iterable):  
    190         """ 连接 """
    191         """
    192         S.join(iterable) -> string
    193         
    194         Return a string which is the concatenation of the strings in the
    195         iterable.  The separator between elements is S.
    196         """
    197         return ""
    198 
    199     def ljust(self, width, fillchar=None):  
    200         """ 内容左对齐,右侧填充 """
    201         """
    202         S.ljust(width[, fillchar]) -> string
    203         
    204         Return S left-justified in a string of length width. Padding is
    205         done using the specified fill character (default is a space).
    206         """
    207         return ""
    208 
    209     def lower(self):  
    210         """ 变小写 """
    211         """
    212         S.lower() -> string
    213         
    214         Return a copy of the string S converted to lowercase.
    215         """
    216         return ""
    217 
    218     def lstrip(self, chars=None):  
    219         """ 移除左侧空白 """
    220         """
    221         S.lstrip([chars]) -> string or unicode
    222         
    223         Return a copy of the string S with leading whitespace removed.
    224         If chars is given and not None, remove characters in chars instead.
    225         If chars is unicode, S will be converted to unicode before stripping
    226         """
    227         return ""
    228 
    229     def partition(self, sep):  
    230         """ 分割,前,中,后三部分 """
    231         """
    232         S.partition(sep) -> (head, sep, tail)
    233         
    234         Search for the separator sep in S, and return the part before it,
    235         the separator itself, and the part after it.  If the separator is not
    236         found, return S and two empty strings.
    237         """
    238         pass
    239 
    240     def replace(self, old, new, count=None):  
    241         """ 替换 """
    242         """
    243         S.replace(old, new[, count]) -> string
    244         
    245         Return a copy of string S with all occurrences of substring
    246         old replaced by new.  If the optional argument count is
    247         given, only the first count occurrences are replaced.
    248         """
    249         return ""
    250 
    251     def rfind(self, sub, start=None, end=None):  
    252         """
    253         S.rfind(sub [,start [,end]]) -> int
    254         
    255         Return the highest index in S where substring sub is found,
    256         such that sub is contained within S[start:end].  Optional
    257         arguments start and end are interpreted as in slice notation.
    258         
    259         Return -1 on failure.
    260         """
    261         return 0
    262 
    263     def rindex(self, sub, start=None, end=None):  
    264         """
    265         S.rindex(sub [,start [,end]]) -> int
    266         
    267         Like S.rfind() but raise ValueError when the substring is not found.
    268         """
    269         return 0
    270 
    271     def rjust(self, width, fillchar=None):  
    272         """
    273         S.rjust(width[, fillchar]) -> string
    274         
    275         Return S right-justified in a string of length width. Padding is
    276         done using the specified fill character (default is a space)
    277         """
    278         return ""
    279 
    280     def rpartition(self, sep):  
    281         """
    282         S.rpartition(sep) -> (head, sep, tail)
    283         
    284         Search for the separator sep in S, starting at the end of S, and return
    285         the part before it, the separator itself, and the part after it.  If the
    286         separator is not found, return two empty strings and S.
    287         """
    288         pass
    289 
    290     def rsplit(self, sep=None, maxsplit=None):  
    291         """
    292         S.rsplit([sep [,maxsplit]]) -> list of strings
    293         
    294         Return a list of the words in the string S, using sep as the
    295         delimiter string, starting at the end of the string and working
    296         to the front.  If maxsplit is given, at most maxsplit splits are
    297         done. If sep is not specified or is None, any whitespace string
    298         is a separator.
    299         """
    300         return []
    301 
    302     def rstrip(self, chars=None):  
    303         """
    304         S.rstrip([chars]) -> string or unicode
    305         
    306         Return a copy of the string S with trailing whitespace removed.
    307         If chars is given and not None, remove characters in chars instead.
    308         If chars is unicode, S will be converted to unicode before stripping
    309         """
    310         return ""
    311 
    312     def split(self, sep=None, maxsplit=None):  
    313         """ 分割, maxsplit最多分割几次 """
    314         """
    315         S.split([sep [,maxsplit]]) -> list of strings
    316         
    317         Return a list of the words in the string S, using sep as the
    318         delimiter string.  If maxsplit is given, at most maxsplit
    319         splits are done. If sep is not specified or is None, any
    320         whitespace string is a separator and empty strings are removed
    321         from the result.
    322         """
    323         return []
    324 
    325     def splitlines(self, keepends=False):  
    326         """ 根据换行分割 """
    327         """
    328         S.splitlines(keepends=False) -> list of strings
    329         
    330         Return a list of the lines in S, breaking at line boundaries.
    331         Line breaks are not included in the resulting list unless keepends
    332         is given and true.
    333         """
    334         return []
    335 
    336     def startswith(self, prefix, start=None, end=None):  
    337         """ 是否起始 """
    338         """
    339         S.startswith(prefix[, start[, end]]) -> bool
    340         
    341         Return True if S starts with the specified prefix, False otherwise.
    342         With optional start, test S beginning at that position.
    343         With optional end, stop comparing S at that position.
    344         prefix can also be a tuple of strings to try.
    345         """
    346         return False
    347 
    348     def strip(self, chars=None):  
    349         """ 移除两段空白 """
    350         """
    351         S.strip([chars]) -> string or unicode
    352         
    353         Return a copy of the string S with leading and trailing
    354         whitespace removed.
    355         If chars is given and not None, remove characters in chars instead.
    356         If chars is unicode, S will be converted to unicode before stripping
    357         """
    358         return ""
    359 
    360     def swapcase(self):  
    361         """ 大写变小写,小写变大写 """
    362         """
    363         S.swapcase() -> string
    364         
    365         Return a copy of the string S with uppercase characters
    366         converted to lowercase and vice versa.
    367         """
    368         return ""
    369 
    370     def title(self):  
    371         """
    372         S.title() -> string
    373         
    374         Return a titlecased version of S, i.e. words start with uppercase
    375         characters, all remaining cased characters have lowercase.
    376         """
    377         return ""
    378 
    379     def translate(self, table, deletechars=None):  
    380         """
    381         转换,需要先做一个对应表,最后一个表示删除字符集合
    382         intab = "aeiou"
    383         outtab = "12345"
    384         trantab = maketrans(intab, outtab)
    385         str = "this is string example....wow!!!"
    386         print str.translate(trantab, 'xm')
    387         """
    388 
    389         """
    390         S.translate(table [,deletechars]) -> string
    391         
    392         Return a copy of the string S, where all characters occurring
    393         in the optional argument deletechars are removed, and the
    394         remaining characters have been mapped through the given
    395         translation table, which must be a string of length 256 or None.
    396         If the table argument is None, no translation is applied and
    397         the operation simply removes the characters in deletechars.
    398         """
    399         return ""
    400 
    401     def upper(self):  
    402         """
    403         S.upper() -> string
    404         
    405         Return a copy of the string S converted to uppercase.
    406         """
    407         return ""
    408 
    409     def zfill(self, width):  
    410         """方法返回指定长度的字符串,原字符串右对齐,前面填充0。"""
    411         """
    412         S.zfill(width) -> string
    413         
    414         Pad a numeric string S with zeros on the left, to fill a field
    415         of the specified width.  The string S is never truncated.
    416         """
    417         return ""
    418 
    419     def _formatter_field_name_split(self, *args, **kwargs): # real signature unknown
    420         pass
    421 
    422     def _formatter_parser(self, *args, **kwargs): # real signature unknown
    423         pass
    424 
    425     def __add__(self, y):  
    426         """ x.__add__(y) <==> x+y """
    427         pass
    428 
    429     def __contains__(self, y):  
    430         """ x.__contains__(y) <==> y in x """
    431         pass
    432 
    433     def __eq__(self, y):  
    434         """ x.__eq__(y) <==> x==y """
    435         pass
    436 
    437     def __format__(self, format_spec):  
    438         """
    439         S.__format__(format_spec) -> string
    440         
    441         Return a formatted version of S as described by format_spec.
    442         """
    443         return ""
    444 
    445     def __getattribute__(self, name):  
    446         """ x.__getattribute__('name') <==> x.name """
    447         pass
    448 
    449     def __getitem__(self, y):  
    450         """ x.__getitem__(y) <==> x[y] """
    451         pass
    452 
    453     def __getnewargs__(self, *args, **kwargs): # real signature unknown
    454         pass
    455 
    456     def __getslice__(self, i, j):  
    457         """
    458         x.__getslice__(i, j) <==> x[i:j]
    459                    
    460                    Use of negative indices is not supported.
    461         """
    462         pass
    463 
    464     def __ge__(self, y):  
    465         """ x.__ge__(y) <==> x>=y """
    466         pass
    467 
    468     def __gt__(self, y):  
    469         """ x.__gt__(y) <==> x>y """
    470         pass
    471 
    472     def __hash__(self):  
    473         """ x.__hash__() <==> hash(x) """
    474         pass
    475 
    476     def __init__(self, string=''): # known special case of str.__init__
    477         """
    478         str(object='') -> string
    479         
    480         Return a nice string representation of the object.
    481         If the argument is a string, the return value is the same object.
    482         # (copied from class doc)
    483         """
    484         pass
    485 
    486     def __len__(self):  
    487         """ x.__len__() <==> len(x) """
    488         pass
    489 
    490     def __le__(self, y):  
    491         """ x.__le__(y) <==> x<=y """
    492         pass
    493 
    494     def __lt__(self, y):  
    495         """ x.__lt__(y) <==> x<y """
    496         pass
    497 
    498     def __mod__(self, y):  
    499         """ x.__mod__(y) <==> x%y """
    500         pass
    501 
    502     def __mul__(self, n):  
    503         """ x.__mul__(n) <==> x*n """
    504         pass
    505 
    506     @staticmethod # known case of __new__
    507     def __new__(S, *more):  
    508         """ T.__new__(S, ...) -> a new object with type S, a subtype of T """
    509         pass
    510 
    511     def __ne__(self, y):  
    512         """ x.__ne__(y) <==> x!=y """
    513         pass
    514 
    515     def __repr__(self):  
    516         """ x.__repr__() <==> repr(x) """
    517         pass
    518 
    519     def __rmod__(self, y):  
    520         """ x.__rmod__(y) <==> y%x """
    521         pass
    522 
    523     def __rmul__(self, n):  
    524         """ x.__rmul__(n) <==> n*x """
    525         pass
    526 
    527     def __sizeof__(self):  
    528         """ S.__sizeof__() -> size of S in memory, in bytes """
    529         pass
    530 
    531     def __str__(self):  
    532         """ x.__str__() <==> str(x) """
    533         pass
    str

    练习代码如下:

      1 name = 'alex' # str类的对象
      2 1. capitalize 字符串首字母大写
      3 自身不变,会生成一个新的值
      4 v = name.capitalize() # 自动找到name关联的str类,执行其中的capitalize技能
      5 print(name)
      6 print(v)
      7 
      8 2. 将所有大小变小写,casefold牛逼,德语...
      9 name = 'AleX'
     10 v = name.casefold() # 跟牛逼,德语...
     11 print(name)
     12 print(v)
     13 
     14 3. 将所有大小变小写
     15 name = 'AleX'
     16 v = name.lower()
     17 print(v)
     18 
     19 4. 文本居中
     20 参数1: 表示总长度
     21 参数2:空白处填充的字符(长度为1)
     22 name = 'alex'
     23 v = name.center(20)
     24 print(v)
     25 v = name.center(20,'')
     26 print(v)
     27 
     28 5. 表示传入之在字符串中出现的次数
     29 参数1: 要查找的值(子序列)
     30 参数2: 起始位置(索引)
     31 参数3: 结束位置(索引)
     32 name = "alexasdfdsafsdfasdfaaaaaaaa"
     33 v = name.count('a')
     34 print(v)
     35 v = name.count('df')
     36 print(v)
     37 
     38 v = name.count('df',12)
     39 print(v)
     40 v = name.count('df',0,15)
     41 print(v)
     42 
     43 6. 是否以xx结尾
     44 name = 'alex'
     45 v1 = name.endswith('ex')
     46 print(v1)
     47 
     48 7. 是否以xx开头
     49 name = 'alex'
     50 v2 = name.startswith('al')
     51 print(v2)
     52 
     53 8. encode欠
     54 
     55 9. 找到制表符	,进行替换(包含前面的值)
     56 PS: 
    
     57 name = "al	e	x
    alex	uu	kkk"
     58 v = name.expandtabs(20)
     59 print(v)
     60 
     61 10. 找到指定子序列的索引位置:不存在返回-1
     62 name = 'alex'
     63 v = name.find('o')
     64 print(v)
     65 v = name.index('o')
     66 print(v)
     67 
     68 11.字符串格式化
     69 
     70 tpl = "我是:%s;年龄:%s;性别:%s"
     71 
     72 tpl = "我是:{0};年龄:{1};性别:{2}"
     73 v = tpl.format("李杰",19,'都行')
     74 print(v)
     75 
     76 tpl = "我是:{name};年龄:{age};性别:{gender}"
     77 v = tpl.format(name='李杰',age=19,gender='随意')
     78 print(v)
     79 
     80 tpl = "我是:{name};年龄:{age};性别:{gender}"
     81 v = tpl.format_map({'name':"李杰",'age':19,'gender':''})
     82 print(v)
     83 
     84 
     85 12. 是否是数字、汉子.
     86 name  = 'alex8汉子'
     87 v = name.isalnum() # 字,数字
     88 print(v) # True
     89 v2 = name.isalpha()#
     90 print(v2)# False
     91 
     92 13. 判断是否是数字
     93 num = ''
     94 v1 = num.isdecimal() # '123'
     95 v2 = num.isdigit()   # '123','②'
     96 v3 = num.isnumeric() # '123','二','②'
     97 print(v1,v2,v3)
     98 
     99 
    100 14. 是否是表示符
    101 n = 'name'
    102 v = n.isidentifier()
    103 print(v)
    104 
    105 15.是否全部是小写
    106 name = "ALEX"
    107 v = name.islower()
    108 print(v)
    109 v = name.isupper()
    110 print(v)
    111 
    112 16,.全部变大写,
    113 name = 'alex'
    114 v = name.upper()  # lower()
    115 print(v)
    116 
    117 17.是否包含隐含的xx
    118 name = "钓鱼要钓刀鱼,
    刀鱼要到岛上钓"
    119 v = name.isprintable()
    120 print(v)
    121 
    122 
    123 18.是否全部是空格
    124 name = '    '
    125 v = name.isspace()
    126 print(v)
    127 
    128 
    129 
    130 19.元素拼接(元素字符串) *****
    131 name = 'alex'
    132 
    133 v = "_".join(name) # 内部循环每个元素
    134 print(v)
    135 
    136 name_list = ['海峰','杠娘','李杰','李泉']
    137 v = "".join(name_list)
    138 print(v)
    139 
    140 20. 左右填充
    141 center,rjust,ljust
    142 name = 'alex'
    143 v = name.rjust(20,'*')
    144 print(v)
    145 
    146 
    147 21. 对应关系 + 翻译
    148 m = str.maketrans('aeiou','12345') # 对应关系
    149 
    150 name = "akpsojfasdufasdlkfj8ausdfakjsdfl;kjer09asdf"
    151 v = name.translate(m)
    152 print(v)
    153 
    154 22. 分割,保留分割的元素
    155 content = "李泉SB刘康SB刘一"
    156 v = content.partition('SB') # partition
    157 print(v)
    158 
    159 23. 替换
    160 content = "李泉SB刘康SB刘浩SB刘一"
    161 v = content.replace('SB','Love')
    162 print(v)
    163 v = content.replace('SB','Love',1)
    164 print(v)
    165 
    166 24,移除空白,
    ,	,自定义
    167 name = 'alex	'
    168 v = name.strip() # 空白,
    ,	
    169 print(v)
    170 
    171 25. 大小写转换
    172 name = "Alex"
    173 v = name.swapcase()
    174 print(v)
    175 
    176 26. 填充0
    177 name = "alex"
    178 v = name.zfill(20)
    179 print(v)
    180 
    181 v1 = 'alex'
    182 v2 = 'eric'
    183 
    184 v = v1 + v2 # 执行v1的__add__功能
    185 print(v)
    常用字符串的语法操作
     1 ##### 字符串功能总结:
     2 name = 'alex'
     3 name.upper()
     4 name.lower()
     5 name.split()
     6 name.find()
     7 name.strip()
     8 name.startswith()
     9 name.format()
    10 name.replace()
    11 "alex".join(["aa",'bb'])
    12 
    13 
    14 ##### 额外功能:
    15 name = "alex"
    16 name[0]
    17 name[0:3]
    18 name[0:3:2]
    19 len(name)
    20 for循环,每个元素是字符

    5、列表

    如:['good','ok']、['apple', 'orange',11]

    每个列表都具备如下功能:

      1 class list(object):
      2     """
      3     list() -> new empty list
      4     list(iterable) -> new list initialized from iterable's items
      5     """
      6     def append(self, p_object): # real signature unknown; restored from __doc__
      7         """ L.append(object) -- append object to end """
      8         pass
      9 
     10     def count(self, value): # real signature unknown; restored from __doc__
     11         """ L.count(value) -> integer -- return number of occurrences of value """
     12         return 0
     13 
     14     def extend(self, iterable): # real signature unknown; restored from __doc__
     15         """ L.extend(iterable) -- extend list by appending elements from the iterable """
     16         pass
     17 
     18     def index(self, value, start=None, stop=None): # real signature unknown; restored from __doc__
     19         """
     20         L.index(value, [start, [stop]]) -> integer -- return first index of value.
     21         Raises ValueError if the value is not present.
     22         """
     23         return 0
     24 
     25     def insert(self, index, p_object): # real signature unknown; restored from __doc__
     26         """ L.insert(index, object) -- insert object before index """
     27         pass
     28 
     29     def pop(self, index=None): # real signature unknown; restored from __doc__
     30         """
     31         L.pop([index]) -> item -- remove and return item at index (default last).
     32         Raises IndexError if list is empty or index is out of range.
     33         """
     34         pass
     35 
     36     def remove(self, value): # real signature unknown; restored from __doc__
     37         """
     38         L.remove(value) -- remove first occurrence of value.
     39         Raises ValueError if the value is not present.
     40         """
     41         pass
     42 
     43     def reverse(self): # real signature unknown; restored from __doc__
     44         """ L.reverse() -- reverse *IN PLACE* """
     45         pass
     46 
     47     def sort(self, cmp=None, key=None, reverse=False): # real signature unknown; restored from __doc__
     48         """
     49         L.sort(cmp=None, key=None, reverse=False) -- stable sort *IN PLACE*;
     50         cmp(x, y) -> -1, 0, 1
     51         """
     52         pass
     53 
     54     def __add__(self, y): # real signature unknown; restored from __doc__
     55         """ x.__add__(y) <==> x+y """
     56         pass
     57 
     58     def __contains__(self, y): # real signature unknown; restored from __doc__
     59         """ x.__contains__(y) <==> y in x """
     60         pass
     61 
     62     def __delitem__(self, y): # real signature unknown; restored from __doc__
     63         """ x.__delitem__(y) <==> del x[y] """
     64         pass
     65 
     66     def __delslice__(self, i, j): # real signature unknown; restored from __doc__
     67         """
     68         x.__delslice__(i, j) <==> del x[i:j]
     69                    
     70                    Use of negative indices is not supported.
     71         """
     72         pass
     73 
     74     def __eq__(self, y): # real signature unknown; restored from __doc__
     75         """ x.__eq__(y) <==> x==y """
     76         pass
     77 
     78     def __getattribute__(self, name): # real signature unknown; restored from __doc__
     79         """ x.__getattribute__('name') <==> x.name """
     80         pass
     81 
     82     def __getitem__(self, y): # real signature unknown; restored from __doc__
     83         """ x.__getitem__(y) <==> x[y] """
     84         pass
     85 
     86     def __getslice__(self, i, j): # real signature unknown; restored from __doc__
     87         """
     88         x.__getslice__(i, j) <==> x[i:j]
     89                    
     90                    Use of negative indices is not supported.
     91         """
     92         pass
     93 
     94     def __ge__(self, y): # real signature unknown; restored from __doc__
     95         """ x.__ge__(y) <==> x>=y """
     96         pass
     97 
     98     def __gt__(self, y): # real signature unknown; restored from __doc__
     99         """ x.__gt__(y) <==> x>y """
    100         pass
    101 
    102     def __iadd__(self, y): # real signature unknown; restored from __doc__
    103         """ x.__iadd__(y) <==> x+=y """
    104         pass
    105 
    106     def __imul__(self, y): # real signature unknown; restored from __doc__
    107         """ x.__imul__(y) <==> x*=y """
    108         pass
    109 
    110     def __init__(self, seq=()): # known special case of list.__init__
    111         """
    112         list() -> new empty list
    113         list(iterable) -> new list initialized from iterable's items
    114         # (copied from class doc)
    115         """
    116         pass
    117 
    118     def __iter__(self): # real signature unknown; restored from __doc__
    119         """ x.__iter__() <==> iter(x) """
    120         pass
    121 
    122     def __len__(self): # real signature unknown; restored from __doc__
    123         """ x.__len__() <==> len(x) """
    124         pass
    125 
    126     def __le__(self, y): # real signature unknown; restored from __doc__
    127         """ x.__le__(y) <==> x<=y """
    128         pass
    129 
    130     def __lt__(self, y): # real signature unknown; restored from __doc__
    131         """ x.__lt__(y) <==> x<y """
    132         pass
    133 
    134     def __mul__(self, n): # real signature unknown; restored from __doc__
    135         """ x.__mul__(n) <==> x*n """
    136         pass
    137 
    138     @staticmethod # known case of __new__
    139     def __new__(S, *more): # real signature unknown; restored from __doc__
    140         """ T.__new__(S, ...) -> a new object with type S, a subtype of T """
    141         pass
    142 
    143     def __ne__(self, y): # real signature unknown; restored from __doc__
    144         """ x.__ne__(y) <==> x!=y """
    145         pass
    146 
    147     def __repr__(self): # real signature unknown; restored from __doc__
    148         """ x.__repr__() <==> repr(x) """
    149         pass
    150 
    151     def __reversed__(self): # real signature unknown; restored from __doc__
    152         """ L.__reversed__() -- return a reverse iterator over the list """
    153         pass
    154 
    155     def __rmul__(self, n): # real signature unknown; restored from __doc__
    156         """ x.__rmul__(n) <==> n*x """
    157         pass
    158 
    159     def __setitem__(self, i, y): # real signature unknown; restored from __doc__
    160         """ x.__setitem__(i, y) <==> x[i]=y """
    161         pass
    162 
    163     def __setslice__(self, i, j, y): # real signature unknown; restored from __doc__
    164         """
    165         x.__setslice__(i, j, y) <==> x[i:j]=y
    166                    
    167                    Use  of negative indices is not supported.
    168         """
    169         pass
    170 
    171     def __sizeof__(self): # real signature unknown; restored from __doc__
    172         """ L.__sizeof__() -- size of L in memory, in bytes """
    173         pass
    174 
    175     __hash__ = None
    176 
    177 list
    list
     1 ########################################## list 列表 ##########################################
     2 ## int=xx; str='xxx'  list='xx'
     3 user_list = ['李泉','刘一','刘康','豆豆','小龙'] # 可变类型
     4 PS:
     5     name = 'alex'
     6 执行功能;
     7 1.追加
     8 user_list = ['李泉','刘一','刘康','豆豆','小龙'] # 可变类型
     9 user_list.append('刘铭')
    10 print(user_list)
    11 2. 清空
    12 user_list = ['李泉','刘一','刘康','豆豆','小龙'] # 可变类型
    13 user_list.clear()
    14 print(user_list)
    15 
    16 3. 拷贝(浅拷贝)
    17 user_list = ['李泉','刘一','刘康','豆豆','小龙'] # 可变类型
    18 v = user_list.copy()
    19 print(v)
    20 print(user_list)
    21 
    22 4. 计数
    23 user_list = ['李泉','刘一','李泉','刘康','豆豆','小龙'] # 可变类型
    24 v = user_list.count('李泉')
    25 print(v)
    26 
    27 5. 扩展原列表
    28 user_list = ['李泉','刘一','李泉','刘康','豆豆','小龙'] # 可变类型
    29 user_list.extend(['郭少龙','郭少霞'])
    30 print(user_list)
    31 
    32 6. 查找元素索引,没有报错
    33 user_list = ['李泉','刘一','李泉','刘康','豆豆','小龙'] # 可变类型
    34 v = user_list.index('李海')
    35 print(v)
    36 
    37 7. 删除并且获取元素 - 索引
    38 user_list = ['李泉','刘一','李泉','刘康','豆豆','小龙'] # 可变类型
    39 v = user_list.pop(1)
    40 print(v)
    41 print(user_list)
    42 
    43 8. 删除 -44 user_list = ['李泉','刘一','李泉','刘康','豆豆','小龙'] # 可变类型
    45 user_list.remove('刘一')
    46 print(user_list)
    47 
    48 9. 翻转
    49 user_list = ['李泉','刘一','李泉','刘康','豆豆','小龙'] # 可变类型
    50 user_list.reverse()
    51 print(user_list)
    52 
    53 10. 排序: 欠参数
    54 nums = [11,22,3,3,9,88]
    55 print(nums)
    56 排序,从小到大
    57 nums.sort()
    58 print(nums)
    59 从大到小
    60 nums.sort(reverse=True)
    61 print(nums)
    62 
    63 #####  额外:
    64 user_list = ['李泉','刘一','李泉','刘康','豆豆','小龙']
    65 user_list[0]
    66 user_list[1:5:2]
    67 del user_list[3]
    68 for i in user_list:
    69     print(i)
    70 user_list[1] = '姜日天'
    71 user_list = ['李泉','刘一','李泉','刘康','豆豆',['日天','日地','泰迪'],'小龙']
    字符串常用语法

    6、元组

    元祖是不可被修改的。

    如:('good','hello',123)、('ziwei', 'qinger','xiaoyanzi')

    每个元组都具备如下功能:

      1 class tuple(object):
      2     """
      3     tuple() -> empty tuple
      4     tuple(iterable) -> tuple initialized from iterable's items
      5     
      6     If the argument is a tuple, the return value is the same object.
      7     """
      8     def count(self, value): # real signature unknown; restored from __doc__
      9         """ T.count(value) -> integer -- return number of occurrences of value """
     10         return 0
     11 
     12     def index(self, value, start=None, stop=None): # real signature unknown; restored from __doc__
     13         """
     14         T.index(value, [start, [stop]]) -> integer -- return first index of value.
     15         Raises ValueError if the value is not present.
     16         """
     17         return 0
     18 
     19     def __add__(self, y): # real signature unknown; restored from __doc__
     20         """ x.__add__(y) <==> x+y """
     21         pass
     22 
     23     def __contains__(self, y): # real signature unknown; restored from __doc__
     24         """ x.__contains__(y) <==> y in x """
     25         pass
     26 
     27     def __eq__(self, y): # real signature unknown; restored from __doc__
     28         """ x.__eq__(y) <==> x==y """
     29         pass
     30 
     31     def __getattribute__(self, name): # real signature unknown; restored from __doc__
     32         """ x.__getattribute__('name') <==> x.name """
     33         pass
     34 
     35     def __getitem__(self, y): # real signature unknown; restored from __doc__
     36         """ x.__getitem__(y) <==> x[y] """
     37         pass
     38 
     39     def __getnewargs__(self, *args, **kwargs): # real signature unknown
     40         pass
     41 
     42     def __getslice__(self, i, j): # real signature unknown; restored from __doc__
     43         """
     44         x.__getslice__(i, j) <==> x[i:j]
     45                    
     46                    Use of negative indices is not supported.
     47         """
     48         pass
     49 
     50     def __ge__(self, y): # real signature unknown; restored from __doc__
     51         """ x.__ge__(y) <==> x>=y """
     52         pass
     53 
     54     def __gt__(self, y): # real signature unknown; restored from __doc__
     55         """ x.__gt__(y) <==> x>y """
     56         pass
     57 
     58     def __hash__(self): # real signature unknown; restored from __doc__
     59         """ x.__hash__() <==> hash(x) """
     60         pass
     61 
     62     def __init__(self, seq=()): # known special case of tuple.__init__
     63         """
     64         tuple() -> empty tuple
     65         tuple(iterable) -> tuple initialized from iterable's items
     66         
     67         If the argument is a tuple, the return value is the same object.
     68         # (copied from class doc)
     69         """
     70         pass
     71 
     72     def __iter__(self): # real signature unknown; restored from __doc__
     73         """ x.__iter__() <==> iter(x) """
     74         pass
     75 
     76     def __len__(self): # real signature unknown; restored from __doc__
     77         """ x.__len__() <==> len(x) """
     78         pass
     79 
     80     def __le__(self, y): # real signature unknown; restored from __doc__
     81         """ x.__le__(y) <==> x<=y """
     82         pass
     83 
     84     def __lt__(self, y): # real signature unknown; restored from __doc__
     85         """ x.__lt__(y) <==> x<y """
     86         pass
     87 
     88     def __mul__(self, n): # real signature unknown; restored from __doc__
     89         """ x.__mul__(n) <==> x*n """
     90         pass
     91 
     92     @staticmethod # known case of __new__
     93     def __new__(S, *more): # real signature unknown; restored from __doc__
     94         """ T.__new__(S, ...) -> a new object with type S, a subtype of T """
     95         pass
     96 
     97     def __ne__(self, y): # real signature unknown; restored from __doc__
     98         """ x.__ne__(y) <==> x!=y """
     99         pass
    100 
    101     def __repr__(self): # real signature unknown; restored from __doc__
    102         """ x.__repr__() <==> repr(x) """
    103         pass
    104 
    105     def __rmul__(self, n): # real signature unknown; restored from __doc__
    106         """ x.__rmul__(n) <==> n*x """
    107         pass
    108 
    109     def __sizeof__(self): # real signature unknown; restored from __doc__
    110         """ T.__sizeof__() -- size of T in memory, in bytes """
    111         pass
    tuple

    常用语法如下:

     1 user_tuple = ('alex','eric','seven','alex')
     2 1. 获取个数
     3 v = user_tuple.count('alex')
     4 print(v)
     5 2.获取值的第一个索引位置
     6 v = user_tuple.index('alex')
     7 print(v)
     8 
     9 ###### 额外:
    10 user_tuple = ('alex','eric','seven','alex')
    11 for i in user_tuple:
    12     print(i)
    13 
    14 v = user_tuple[0]
    15 
    16 v = user_tuple[0:2]
    17 print(v)
    18 
    19 user_tuple = ('alex','eric','seven',['陈涛','刘浩','赵芬芬'],'alex')
    20 user_tuple[0] = 123   x
    21 user_tuple[3] = [11,22,33] x
    22 user_tuple[3][1] = '刘一'
    23 print(user_tuple)
    24 
    25 li = ['陈涛','刘浩',('alex','eric','seven'),'赵芬芬']
    26 ****** 元组最后,加逗号 ******
    27 li = ('alex',)
    28 print(li)
    元祖常用语法

    7、字典

    如:{'name': 'oliver', 'age': 33,'id':12345} 、{'host': '1.1.1.1', 'port': 21]}

    ps:循环时,默认循环key

    每个字典都具备如下功能:

      1 class dict(object):
      2     """
      3     dict() -> new empty dictionary
      4     dict(mapping) -> new dictionary initialized from a mapping object's
      5         (key, value) pairs
      6     dict(iterable) -> new dictionary initialized as if via:
      7         d = {}
      8         for k, v in iterable:
      9             d[k] = v
     10     dict(**kwargs) -> new dictionary initialized with the name=value pairs
     11         in the keyword argument list.  For example:  dict(one=1, two=2)
     12     """
     13 
     14     def clear(self): # real signature unknown; restored from __doc__
     15         """ 清除内容 """
     16         """ D.clear() -> None.  Remove all items from D. """
     17         pass
     18 
     19     def copy(self): # real signature unknown; restored from __doc__
     20         """ 浅拷贝 """
     21         """ D.copy() -> a shallow copy of D """
     22         pass
     23 
     24     @staticmethod # known case
     25     def fromkeys(S, v=None): # real signature unknown; restored from __doc__
     26         """
     27         dict.fromkeys(S[,v]) -> New dict with keys from S and values equal to v.
     28         v defaults to None.
     29         """
     30         pass
     31 
     32     def get(self, k, d=None): # real signature unknown; restored from __doc__
     33         """ 根据key获取值,d是默认值 """
     34         """ D.get(k[,d]) -> D[k] if k in D, else d.  d defaults to None. """
     35         pass
     36 
     37     def has_key(self, k): # real signature unknown; restored from __doc__
     38         """ 是否有key """
     39         """ D.has_key(k) -> True if D has a key k, else False """
     40         return False
     41 
     42     def items(self): # real signature unknown; restored from __doc__
     43         """ 所有项的列表形式 """
     44         """ D.items() -> list of D's (key, value) pairs, as 2-tuples """
     45         return []
     46 
     47     def iteritems(self): # real signature unknown; restored from __doc__
     48         """ 项可迭代 """
     49         """ D.iteritems() -> an iterator over the (key, value) items of D """
     50         pass
     51 
     52     def iterkeys(self): # real signature unknown; restored from __doc__
     53         """ key可迭代 """
     54         """ D.iterkeys() -> an iterator over the keys of D """
     55         pass
     56 
     57     def itervalues(self): # real signature unknown; restored from __doc__
     58         """ value可迭代 """
     59         """ D.itervalues() -> an iterator over the values of D """
     60         pass
     61 
     62     def keys(self): # real signature unknown; restored from __doc__
     63         """ 所有的key列表 """
     64         """ D.keys() -> list of D's keys """
     65         return []
     66 
     67     def pop(self, k, d=None): # real signature unknown; restored from __doc__
     68         """ 获取并在字典中移除 """
     69         """
     70         D.pop(k[,d]) -> v, remove specified key and return the corresponding value.
     71         If key is not found, d is returned if given, otherwise KeyError is raised
     72         """
     73         pass
     74 
     75     def popitem(self): # real signature unknown; restored from __doc__
     76         """ 获取并在字典中移除 """
     77         """
     78         D.popitem() -> (k, v), remove and return some (key, value) pair as a
     79         2-tuple; but raise KeyError if D is empty.
     80         """
     81         pass
     82 
     83     def setdefault(self, k, d=None): # real signature unknown; restored from __doc__
     84         """ 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 """
     85         """ D.setdefault(k[,d]) -> D.get(k,d), also set D[k]=d if k not in D """
     86         pass
     87 
     88     def update(self, E=None, **F): # known special case of dict.update
     89         """ 更新
     90             {'name':'alex', 'age': 18000}
     91             [('name','sbsbsb'),]
     92         """
     93         """
     94         D.update([E, ]**F) -> None.  Update D from dict/iterable E and F.
     95         If E present and has a .keys() method, does:     for k in E: D[k] = E[k]
     96         If E present and lacks .keys() method, does:     for (k, v) in E: D[k] = v
     97         In either case, this is followed by: for k in F: D[k] = F[k]
     98         """
     99         pass
    100 
    101     def values(self): # real signature unknown; restored from __doc__
    102         """ 所有的值 """
    103         """ D.values() -> list of D's values """
    104         return []
    105 
    106     def viewitems(self): # real signature unknown; restored from __doc__
    107         """ 所有项,只是将内容保存至view对象中 """
    108         """ D.viewitems() -> a set-like object providing a view on D's items """
    109         pass
    110 
    111     def viewkeys(self): # real signature unknown; restored from __doc__
    112         """ D.viewkeys() -> a set-like object providing a view on D's keys """
    113         pass
    114 
    115     def viewvalues(self): # real signature unknown; restored from __doc__
    116         """ D.viewvalues() -> an object providing a view on D's values """
    117         pass
    118 
    119     def __cmp__(self, y): # real signature unknown; restored from __doc__
    120         """ x.__cmp__(y) <==> cmp(x,y) """
    121         pass
    122 
    123     def __contains__(self, k): # real signature unknown; restored from __doc__
    124         """ D.__contains__(k) -> True if D has a key k, else False """
    125         return False
    126 
    127     def __delitem__(self, y): # real signature unknown; restored from __doc__
    128         """ x.__delitem__(y) <==> del x[y] """
    129         pass
    130 
    131     def __eq__(self, y): # real signature unknown; restored from __doc__
    132         """ x.__eq__(y) <==> x==y """
    133         pass
    134 
    135     def __getattribute__(self, name): # real signature unknown; restored from __doc__
    136         """ x.__getattribute__('name') <==> x.name """
    137         pass
    138 
    139     def __getitem__(self, y): # real signature unknown; restored from __doc__
    140         """ x.__getitem__(y) <==> x[y] """
    141         pass
    142 
    143     def __ge__(self, y): # real signature unknown; restored from __doc__
    144         """ x.__ge__(y) <==> x>=y """
    145         pass
    146 
    147     def __gt__(self, y): # real signature unknown; restored from __doc__
    148         """ x.__gt__(y) <==> x>y """
    149         pass
    150 
    151     def __init__(self, seq=None, **kwargs): # known special case of dict.__init__
    152         """
    153         dict() -> new empty dictionary
    154         dict(mapping) -> new dictionary initialized from a mapping object's
    155             (key, value) pairs
    156         dict(iterable) -> new dictionary initialized as if via:
    157             d = {}
    158             for k, v in iterable:
    159                 d[k] = v
    160         dict(**kwargs) -> new dictionary initialized with the name=value pairs
    161             in the keyword argument list.  For example:  dict(one=1, two=2)
    162         # (copied from class doc)
    163         """
    164         pass
    165 
    166     def __iter__(self): # real signature unknown; restored from __doc__
    167         """ x.__iter__() <==> iter(x) """
    168         pass
    169 
    170     def __len__(self): # real signature unknown; restored from __doc__
    171         """ x.__len__() <==> len(x) """
    172         pass
    173 
    174     def __le__(self, y): # real signature unknown; restored from __doc__
    175         """ x.__le__(y) <==> x<=y """
    176         pass
    177 
    178     def __lt__(self, y): # real signature unknown; restored from __doc__
    179         """ x.__lt__(y) <==> x<y """
    180         pass
    181 
    182     @staticmethod # known case of __new__
    183     def __new__(S, *more): # real signature unknown; restored from __doc__
    184         """ T.__new__(S, ...) -> a new object with type S, a subtype of T """
    185         pass
    186 
    187     def __ne__(self, y): # real signature unknown; restored from __doc__
    188         """ x.__ne__(y) <==> x!=y """
    189         pass
    190 
    191     def __repr__(self): # real signature unknown; restored from __doc__
    192         """ x.__repr__() <==> repr(x) """
    193         pass
    194 
    195     def __setitem__(self, i, y): # real signature unknown; restored from __doc__
    196         """ x.__setitem__(i, y) <==> x[i]=y """
    197         pass
    198 
    199     def __sizeof__(self): # real signature unknown; restored from __doc__
    200         """ D.__sizeof__() -> size of D in memory, in bytes """
    201         pass
    202 
    203     __hash__ = None
    dict

    字典常用语法如下:

     1 1. 清空、
     2 dic = {'k1':'v1','k2':'v2'}
     3 dic.clear()
     4 print(dic)
     5 
     6 2. 浅拷贝
     7 dic = {'k1':'v1','k2':'v2'}
     8 v = dic.copy()
     9 print(v)
    10 
    11 3. 根据key获取指定的value;不存在不报错
    12 dic = {'k1':'v1','k2':'v2'}
    13 v = dic.get('k1111',1111)
    14 print(v)
    15 v = dic['k1111']
    16 print(v)
    17 
    18 4. 删除并获取对应的value值
    19 dic = {'k1':'v1','k2':'v2'}
    20 v = dic.pop('k1')
    21 print(dic)
    22 print(v)
    23 
    24 5. 随机删除键值对,并获取到删除的键值
    25 dic = {'k1':'v1','k2':'v2'}
    26 v = dic.popitem()
    27 print(dic)
    28 print(v)
    29 
    30 k,v = dic.popitem() # ('k2', 'v2')
    31 print(dic)
    32 print(k,v)
    33 
    34 v = dic.popitem() # ('k2', 'v2')
    35 print(dic)
    36 print(v[0],v[1])
    37 
    38 6. 增加,如果存在则不做操作
    39 dic = {'k1':'v1','k2':'v2'}
    40 dic.setdefault('k3','v3')
    41 print(dic)
    42 dic.setdefault('k1','1111111')
    43 print(dic)
    44 7. 批量增加或修改
    45 dic = {'k1':'v1','k2':'v2'}
    46 dic.update({'k3':'v3','k1':'v24'})
    47 print(dic)
    48 
    49 
    50 dic = dict.fromkeys(['k1','k2','k3'],123)
    51 print(dic)
    52 dic = dict.fromkeys(['k1','k2','k3'],123)
    53 dic['k1'] = 'asdfjasldkf'
    54 print(dic)
    55 
    56 dic = dict.fromkeys(['k1','k2','k3'],[1,])
    57 {
    58    k1: 123123213, # [1,2]
    59    k2: 123123213, # [1,]
    60    k3: 123123213, # [1,]
    61 }
    62 dic['k1'].append(222)
    63 print(dic)
    64 ########## 额外:
    65 - 字典可以嵌套
    66 - 字典key: 必须是不可变类型
    67 dic = {
    68     'k1': 'v1',
    69     'k2': [1,2,3,],
    70     (1,2): 'lllll',
    71     1: 'fffffffff',
    72     111: 'asdf',
    73 }
    74 print(dic)
    75 key:
    76     - 不可变
    77     - True,1
    78 
    79 dic = {'k1':'v1'}
    80 del dic['k1']
    81 
    82 布尔值:
    83 1 True
    84 0 False
    85 
    86 bool(1111)
    字典常用语法

    8、

    set集合

    set是一个无序且不重复的元素集合,是一个可变类型

      1 class set(object):
      2     """
      3     set() -> new empty set object
      4     set(iterable) -> new set object
      5     
      6     Build an unordered collection of unique elements.
      7     """
      8     def add(self, *args, **kwargs): # real signature unknown
      9         """ 添加 """
     10         """
     11         Add an element to a set.
     12         
     13         This has no effect if the element is already present.
     14         """
     15         pass
     16 
     17     def clear(self, *args, **kwargs): # real signature unknown
     18         """ Remove all elements from this set. """
     19         pass
     20 
     21     def copy(self, *args, **kwargs): # real signature unknown
     22         """ Return a shallow copy of a set. """
     23         pass
     24 
     25     def difference(self, *args, **kwargs): # real signature unknown
     26         """
     27         Return the difference of two or more sets as a new set.
     28         
     29         (i.e. all elements that are in this set but not the others.)
     30         """
     31         pass
     32 
     33     def difference_update(self, *args, **kwargs): # real signature unknown
     34         """ 删除当前set中的所有包含在 new set 里的元素 """
     35         """ Remove all elements of another set from this set. """
     36         pass
     37 
     38     def discard(self, *args, **kwargs): # real signature unknown
     39         """ 移除元素 """
     40         """
     41         Remove an element from a set if it is a member.
     42         
     43         If the element is not a member, do nothing.
     44         """
     45         pass
     46 
     47     def intersection(self, *args, **kwargs): # real signature unknown
     48         """ 取交集,新创建一个set """
     49         """
     50         Return the intersection of two or more sets as a new set.
     51         
     52         (i.e. elements that are common to all of the sets.)
     53         """
     54         pass
     55 
     56     def intersection_update(self, *args, **kwargs): # real signature unknown
     57         """ 取交集,修改原来set """
     58         """ Update a set with the intersection of itself and another. """
     59         pass
     60 
     61     def isdisjoint(self, *args, **kwargs): # real signature unknown
     62         """ 如果没有交集,返回true  """
     63         """ Return True if two sets have a null intersection. """
     64         pass
     65 
     66     def issubset(self, *args, **kwargs): # real signature unknown
     67         """ 是否是子集 """
     68         """ Report whether another set contains this set. """
     69         pass
     70 
     71     def issuperset(self, *args, **kwargs): # real signature unknown
     72         """ 是否是父集 """
     73         """ Report whether this set contains another set. """
     74         pass
     75 
     76     def pop(self, *args, **kwargs): # real signature unknown
     77         """ 移除 """
     78         """
     79         Remove and return an arbitrary set element.
     80         Raises KeyError if the set is empty.
     81         """
     82         pass
     83 
     84     def remove(self, *args, **kwargs): # real signature unknown
     85         """ 移除 """
     86         """
     87         Remove an element from a set; it must be a member.
     88         
     89         If the element is not a member, raise a KeyError.
     90         """
     91         pass
     92 
     93     def symmetric_difference(self, *args, **kwargs): # real signature unknown
     94         """ 差集,创建新对象"""
     95         """
     96         Return the symmetric difference of two sets as a new set.
     97         
     98         (i.e. all elements that are in exactly one of the sets.)
     99         """
    100         pass
    101 
    102     def symmetric_difference_update(self, *args, **kwargs): # real signature unknown
    103         """ 差集,改变原来 """
    104         """ Update a set with the symmetric difference of itself and another. """
    105         pass
    106 
    107     def union(self, *args, **kwargs): # real signature unknown
    108         """ 并集 """
    109         """
    110         Return the union of sets as a new set.
    111         
    112         (i.e. all elements that are in either set.)
    113         """
    114         pass
    115 
    116     def update(self, *args, **kwargs): # real signature unknown
    117         """ 更新 """
    118         """ Update a set with the union of itself and others. """
    119         pass
    120 
    121     def __and__(self, y): # real signature unknown; restored from __doc__
    122         """ x.__and__(y) <==> x&y """
    123         pass
    124 
    125     def __cmp__(self, y): # real signature unknown; restored from __doc__
    126         """ x.__cmp__(y) <==> cmp(x,y) """
    127         pass
    128 
    129     def __contains__(self, y): # real signature unknown; restored from __doc__
    130         """ x.__contains__(y) <==> y in x. """
    131         pass
    132 
    133     def __eq__(self, y): # real signature unknown; restored from __doc__
    134         """ x.__eq__(y) <==> x==y """
    135         pass
    136 
    137     def __getattribute__(self, name): # real signature unknown; restored from __doc__
    138         """ x.__getattribute__('name') <==> x.name """
    139         pass
    140 
    141     def __ge__(self, y): # real signature unknown; restored from __doc__
    142         """ x.__ge__(y) <==> x>=y """
    143         pass
    144 
    145     def __gt__(self, y): # real signature unknown; restored from __doc__
    146         """ x.__gt__(y) <==> x>y """
    147         pass
    148 
    149     def __iand__(self, y): # real signature unknown; restored from __doc__
    150         """ x.__iand__(y) <==> x&=y """
    151         pass
    152 
    153     def __init__(self, seq=()): # known special case of set.__init__
    154         """
    155         set() -> new empty set object
    156         set(iterable) -> new set object
    157         
    158         Build an unordered collection of unique elements.
    159         # (copied from class doc)
    160         """
    161         pass
    162 
    163     def __ior__(self, y): # real signature unknown; restored from __doc__
    164         """ x.__ior__(y) <==> x|=y """
    165         pass
    166 
    167     def __isub__(self, y): # real signature unknown; restored from __doc__
    168         """ x.__isub__(y) <==> x-=y """
    169         pass
    170 
    171     def __iter__(self): # real signature unknown; restored from __doc__
    172         """ x.__iter__() <==> iter(x) """
    173         pass
    174 
    175     def __ixor__(self, y): # real signature unknown; restored from __doc__
    176         """ x.__ixor__(y) <==> x^=y """
    177         pass
    178 
    179     def __len__(self): # real signature unknown; restored from __doc__
    180         """ x.__len__() <==> len(x) """
    181         pass
    182 
    183     def __le__(self, y): # real signature unknown; restored from __doc__
    184         """ x.__le__(y) <==> x<=y """
    185         pass
    186 
    187     def __lt__(self, y): # real signature unknown; restored from __doc__
    188         """ x.__lt__(y) <==> x<y """
    189         pass
    190 
    191     @staticmethod # known case of __new__
    192     def __new__(S, *more): # real signature unknown; restored from __doc__
    193         """ T.__new__(S, ...) -> a new object with type S, a subtype of T """
    194         pass
    195 
    196     def __ne__(self, y): # real signature unknown; restored from __doc__
    197         """ x.__ne__(y) <==> x!=y """
    198         pass
    199 
    200     def __or__(self, y): # real signature unknown; restored from __doc__
    201         """ x.__or__(y) <==> x|y """
    202         pass
    203 
    204     def __rand__(self, y): # real signature unknown; restored from __doc__
    205         """ x.__rand__(y) <==> y&x """
    206         pass
    207 
    208     def __reduce__(self, *args, **kwargs): # real signature unknown
    209         """ Return state information for pickling. """
    210         pass
    211 
    212     def __repr__(self): # real signature unknown; restored from __doc__
    213         """ x.__repr__() <==> repr(x) """
    214         pass
    215 
    216     def __ror__(self, y): # real signature unknown; restored from __doc__
    217         """ x.__ror__(y) <==> y|x """
    218         pass
    219 
    220     def __rsub__(self, y): # real signature unknown; restored from __doc__
    221         """ x.__rsub__(y) <==> y-x """
    222         pass
    223 
    224     def __rxor__(self, y): # real signature unknown; restored from __doc__
    225         """ x.__rxor__(y) <==> y^x """
    226         pass
    227 
    228     def __sizeof__(self): # real signature unknown; restored from __doc__
    229         """ S.__sizeof__() -> size of S in memory, in bytes """
    230         pass
    231 
    232     def __sub__(self, y): # real signature unknown; restored from __doc__
    233         """ x.__sub__(y) <==> x-y """
    234         pass
    235 
    236     def __xor__(self, y): # real signature unknown; restored from __doc__
    237         """ x.__xor__(y) <==> x^y """
    238         pass
    239 
    240     __hash__ = None
    241 
    242 set
    set
    三元运算

    如果条件成立,那么就把值1赋值给var,如果条件不成立,就把值2赋值给var

    1 var = 值1 if 条件 else 值2
    1 例子:
    2 >>> var = "True" if 1==1 else "False"
    3 >>> var
    4 'True'
     1 ##################################### set,集合,不可重复的列表;可变类型 #####################################
     2 s1 = {"alex",'eric','tony','李泉','李泉11'}
     3 s2 = {"alex",'eric','tony','刘一'}
     4 
     5 1.s1中存在,s2中不存在
     6 v = s1.difference(s2)
     7 print(v)
     8 #### s1中存在,s2中不存在,然后对s1清空,然后在重新复制
     9 s1.difference_update(s2)
    10 print(s1)
    11 
    12 2.s2中存在,s1中不存在
    13 v = s2.difference(s1)
    14 print(v)
    15 
    16 3.s2中存在,s1中不存在
    17 s1中存在,s2中不存在
    18 v = s1.symmetric_difference(s2)
    19 print(v)
    20 4. 交集
    21 v = s1.intersection(s2)
    22 print(v)
    23 5. 并集
    24 v = s1.union(s2)
    25 print(v)
    26 
    27 6. 移除
    28 s1 = {"alex",'eric','tony','李泉','李泉11'}
    29 s1.discard('alex')
    30 print(s1)
    31 
    32 s1 = {"alex",'eric','tony','李泉','李泉11'}
    33 s1.update({'alex','123123','fff'})
    34 print(s1)
    35 ##### 额外:
    36 
    37 s1 = {"alex",'eric','tony','李泉','李泉11'}
    38 for i in s1:
    39     print(i)
    40 
    41 s1 = {"alex",'eric','tony','李泉','李泉11',(11,22,33)}
    42 for i in s1:
    43     print(i)
    set常用语法
    深拷贝和浅拷贝

     对于数字字符串而言,赋值、浅拷贝和深拷贝无意义,因为他们的值永远都会指向同一个内存地址。

    对于字典、元祖、列表 而言,进行赋值、浅拷贝和深拷贝时,其内存地址的变化是不同的。

    Python中,对象的赋值,拷贝(深/浅拷贝)之间是有差异的,如果使用的时候不注意,就可能产生意外的结果。

    对象赋值

     1 #-*-coding:utf-8-*-
     2 #!/usr/bin/env python
     3 __author__ = 'mengxj'
     4 
     5 will = ["Will", 28, ["Python", "C#", "JavaScript"]]
     6 wilber = will
     7 print ('will的内存指向',id(will))
     8 print ('will的数据',will)
     9 print ('每一个元素的地址',[id(ele) for ele in will])
    10 print ('willer的内存指向',id(wilber))
    11 print ('willer的数据',wilber)
    12 print ('每一个元素的地址',[id(ele) for ele in wilber])
    13 
    14 will[0] = "Wilber"
    15 will[2].append("CSS")
    16 print ('数据更改后的will内存指向',id(will))
    17 print ('数据更改后的will的数据',will)
    18 print ('数据更改后每一个元素的地址',[id(ele) for ele in will])
    19 print ('数据更改后wilber的内存指向',id(wilber))
    20 print ('数据更改后wilber的内容',wilber)
    21 print ('数据更改后wilber的内存地址',[id(ele) for ele in wilber])

    代码运行结果如下:

     1 C:Python35python.exe D:/OneDrive/python_code/python_s14/s14_day2/deep_copy_and_shadow_copy.py
     2 will的内存指向 2427689548744
     3 will的数据 ['Will', 28, ['Python', 'C#', 'JavaScript']]
     4 每一个元素的地址 [2427689542464, 1516176688, 2427689571720]
     5 willer的内存指向 2427689548744
     6 willer的数据 ['Will', 28, ['Python', 'C#', 'JavaScript']]
     7 每一个元素的地址 [2427689542464, 1516176688, 2427689571720]
     8 数据更改后的will内存指向 2427689548744
     9 数据更改后的will的数据 ['Wilber', 28, ['Python', 'C#', 'JavaScript', 'CSS']]
    10 数据更改后每一个元素的地址 [2427689578768, 1516176688, 2427689571720]
    11 数据更改后wilber的内存指向 2427689548744
    12 数据更改后wilber的内容 ['Wilber', 28, ['Python', 'C#', 'JavaScript', 'CSS']]
    13 数据更改后wilber的内存地址 [2427689578768, 1516176688, 2427689571720]
    14 
    15 Process finished with exit code 0

     如下图展示:

    2、浅拷贝

     1 #浅拷贝
     2 import copy
     3 
     4 will = ["Will", 28, ["Python", "C#", "JavaScript"]]
     5 wilber = copy.copy(will)
     6 print ('will的内存指向',id(will))
     7 print ('will的数据',will)
     8 print ('will每一个元素的地址',[id(ele) for ele in will])
     9 print ('willer的内存指向',id(wilber))
    10 print ('willer的数据',wilber)
    11 print ('willer每一个元素的地址',[id(ele) for ele in wilber])
    12 
    13 will[0] = "Wilber"
    14 will[2].append("CSS")
    15 print ('数据更改后的will内存指向',id(will))
    16 print ('数据更改后的will的数据',will)
    17 print ('数据更改后will每一个元素的地址',[id(ele) for ele in will])
    18 print ('数据更改后wilber的内存指向',id(wilber))
    19 print ('数据更改后wilber的内容',wilber)
    20 print ('数据更改后wilber的内存地址',[id(ele) for ele in wilber])

    输出结果如下:

     1 will的内存指向 2484908535112
     2 will的数据 ['Will', 28, ['Python', 'C#', 'JavaScript']]
     3 will每一个元素的地址 [2484907057984, 1392903472, 2484908643272]
     4 willer的内存指向 2484907111560
     5 willer的数据 ['Will', 28, ['Python', 'C#', 'JavaScript']]
     6 willer每一个元素的地址 [2484907057984, 1392903472, 2484908643272]
     7 数据更改后的will内存指向 2484908535112
     8 数据更改后的will的数据 ['Wilber', 28, ['Python', 'C#', 'JavaScript', 'CSS']]
     9 数据更改后will每一个元素的地址 [2484907094232, 1392903472, 2484908643272]
    10 数据更改后wilber的内存指向 2484907111560
    11 数据更改后wilber的内容 ['Will', 28, ['Python', 'C#', 'JavaScript', 'CSS']]
    12 数据更改后wilber的内存地址 [2484907057984, 1392903472, 2484908643272]

    由于list的第一个元素是不可变类型,所以will对应的list的第一个元素会使用一个新的对象
    但是list的第三个元素是一个可变类型,修改操作不会产生新的对象,所以will的修改结果会相应的反应到wilber上

    总结一下,当我们使用下面的操作的时候,会产生浅拷贝的效果:

    • 使用切片[:]操作
    • 使用工厂函数(如list/dir/set)
    • 使用copy模块中的copy()函数

    3、深拷贝

    代码如下:

     1 #深拷贝
     2 import copy
     3 
     4 will = ["Will", 28, ["Python", "C#", "JavaScript"]]
     5 wilber = copy.deepcopy(will)
     6 print ('will的内存指向',id(will))
     7 print ('will的数据',will)
     8 print ('will每一个元素的地址',[id(ele) for ele in will])
     9 print ('willer的内存指向',id(wilber))
    10 print ('willer的数据',wilber)
    11 print ('willer每一个元素的地址',[id(ele) for ele in wilber])
    12 
    13 will[0] = "Wilber"
    14 will[2].append("CSS")
    15 print ('数据更改后的will内存指向',id(will))
    16 print ('数据更改后的will的数据',will)
    17 print ('数据更改后will每一个元素的地址',[id(ele) for ele in will])
    18 print ('数据更改后wilber的内存指向',id(wilber))
    19 print ('数据更改后wilber的内容',wilber)
    20 print ('数据更改后wilber的内存地址',[id(ele) for ele in wilber])

    运行结果如下:

     1 will的内存指向 2941900762440
     2 will的数据 ['Will', 28, ['Python', 'C#', 'JavaScript']]
     3 will每一个元素的地址 [2941899285368, 1392903472, 2941900870984]
     4 willer的内存指向 2941900762952
     5 willer的数据 ['Will', 28, ['Python', 'C#', 'JavaScript']]
     6 willer每一个元素的地址 [2941899285368, 1392903472, 2941900871048]
     7 数据更改后的will内存指向 2941900762440
     8 数据更改后的will的数据 ['Wilber', 28, ['Python', 'C#', 'JavaScript', 'CSS']]
     9 数据更改后will每一个元素的地址 [2941899321560, 1392903472, 2941900870984]
    10 数据更改后wilber的内存指向 2941900762952
    11 数据更改后wilber的内容 ['Will', 28, ['Python', 'C#', 'JavaScript']]
    12 数据更改后wilber的内存地址 [2941899285368, 1392903472, 2941900871048]

    由于list的第一个元素是不可变类型,所以will对应的list的第一个元素会使用一个新的对象39758496
    但是list的第三个元素是一个可不类型,修改操作不会产生新的对象,但是由于”wilber[2] is not will[2]”,所以will的修改不会影响wilber

    拷贝的特殊情况

    其实,对于拷贝有一些特殊情况:

    • 对于非容器类型(如数字、字符串、和其他’原子’类型的对象)没有拷贝这一说

    也就是说,对于这些类型,”obj is copy.copy(obj)” 、”obj is copy.deepcopy(obj)”

    总结

    本文介绍了对象的赋值和拷贝,以及它们之间的差异:

    • Python中对象的赋值都是进行对象引用(内存地址)传递
    • 使用copy.copy(),可以进行对象的浅拷贝,它复制了对象,但对于对象中的元素,依然使用原始的引用.
    • 如果需要复制一个容器对象,以及它里面的所有元素(包含元素的子元素),可以使用copy.deepcopy()进行深拷贝
    • 对于非容器类型(如数字、字符串、和其他’原子’类型的对象)没有被拷贝一说
    • 如果元祖变量只包含原子类型对象,则不能深拷贝,看下面的例子

    关于赋值、浅拷贝和深拷贝的区别如下:

    http://python.jobbole.com/82294/

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  • 原文地址:https://www.cnblogs.com/bravexz/p/5724733.html
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