python 基本数据类型分析
在python中，一切都是对象！对象由类创建而来，对象所拥有的功能都来自于类。在本节中，我们了解一下python基本数据类型对象具有哪些功能，我们平常是怎么使用的。
对于python，一切事物都是对象，对象基于类创建
一、整数：int 类源码分析
整数如：1,2,3... 2147483647
class int(object): """ int(x=0) -> int or long int(x, base=10) -> int or long Convert a number or string to an integer, or return 0 if no arguments are given. If x is floating point, the conversion truncates towards zero. If x is outside the integer range, the function returns a long instead. If x is not a number or if base is given, then x must be a string or Unicode object representing an integer literal in the given base. The literal can be preceded by '+' or '-' and be surrounded by whitespace. The base defaults to 10. Valid bases are 0 and 2-36. Base 0 means to interpret the base from the string as an integer literal. >>> int('0b100', base=0) 4 """ def bit_length(self): # real signature unknown; restored from __doc__ """ int.bit_length() -> int Number of bits necessary to represent self in binary. >>> bin(37) '0b100101' >>> (37).bit_length() 6 """ return 0 def conjugate(self, *args, **kwargs): # real signature unknown """ Returns self, the complex conjugate of any int. """ pass def __abs__(self): # real signature unknown; restored from __doc__ """ x.__abs__() <==> abs(x) """ pass def __add__(self, y): # real signature unknown; restored from __doc__ """ x.__add__(y) <==> x+y """ pass def __and__(self, y): # real signature unknown; restored from __doc__ """ x.__and__(y) <==> x&y """ pass def __cmp__(self, y): # real signature unknown; restored from __doc__ """ x.__cmp__(y) <==> cmp(x,y) """ pass def __coerce__(self, y): # real signature unknown; restored from __doc__ """ x.__coerce__(y) <==> coerce(x, y) """ pass def __divmod__(self, y): # real signature unknown; restored from __doc__ """ x.__divmod__(y) <==> divmod(x, y) """ pass def __div__(self, y): # real signature unknown; restored from __doc__ """ x.__div__(y) <==> x/y """ pass def __float__(self): # real signature unknown; restored from __doc__ """ x.__float__() <==> float(x) """ pass def __floordiv__(self, y): # real signature unknown; restored from __doc__ """ x.__floordiv__(y) <==> x//y """ pass def __format__(self, *args, **kwargs): # real signature unknown pass def __getattribute__(self, name): # real signature unknown; restored from __doc__ """ x.__getattribute__('name') <==> x.name """ pass def __getnewargs__(self, *args, **kwargs): # real signature unknown pass def __hash__(self): # real signature unknown; restored from __doc__ """ x.__hash__() <==> hash(x) """ pass def __hex__(self): # real signature unknown; restored from __doc__ """ x.__hex__() <==> hex(x) """ pass def __index__(self): # real signature unknown; restored from __doc__ """ x[y:z] <==> x[y.__index__():z.__index__()] """ pass def __init__(self, x, base=10): # known special case of int.__init__ """ int(x=0) -> int or long int(x, base=10) -> int or long Convert a number or string to an integer, or return 0 if no arguments are given. If x is floating point, the conversion truncates towards zero. If x is outside the integer range, the function returns a long instead. If x is not a number or if base is given, then x must be a string or Unicode object representing an integer literal in the given base. The literal can be preceded by '+' or '-' and be surrounded by whitespace. The base defaults to 10. Valid bases are 0 and 2-36. Base 0 means to interpret the base from the string as an integer literal. >>> int('0b100', base=0) 4 # (copied from class doc) """ pass def __int__(self): # real signature unknown; restored from __doc__ """ x.__int__() <==> int(x) """ pass def __invert__(self): # real signature unknown; restored from __doc__ """ x.__invert__() <==> ~x """ pass def __long__(self): # real signature unknown; restored from __doc__ """ x.__long__() <==> long(x) """ pass def __lshift__(self, y): # real signature unknown; restored from __doc__ """ x.__lshift__(y) <==> x<<y """ pass def __mod__(self, y): # real signature unknown; restored from __doc__ """ x.__mod__(y) <==> x%y """ pass def __mul__(self, y): # real signature unknown; restored from __doc__ """ x.__mul__(y) <==> x*y """ pass def __neg__(self): # real signature unknown; restored from __doc__ """ x.__neg__() <==> -x """ pass @staticmethod # known case of __new__ def __new__(S, *more): # real signature unknown; restored from __doc__ """ T.__new__(S, ...) -> a new object with type S, a subtype of T """ pass def __nonzero__(self): # real signature unknown; restored from __doc__ """ x.__nonzero__() <==> x != 0 """ pass def __oct__(self): # real signature unknown; restored from __doc__ """ x.__oct__() <==> oct(x) """ pass def __or__(self, y): # real signature unknown; restored from __doc__ """ x.__or__(y) <==> x|y """ pass def __pos__(self): # real signature unknown; restored from __doc__ """ x.__pos__() <==> +x """ pass def __pow__(self, y, z=None): # real signature unknown; restored from __doc__ """ x.__pow__(y[, z]) <==> pow(x, y[, z]) """ pass def __radd__(self, y): # real signature unknown; restored from __doc__ """ x.__radd__(y) <==> y+x """ pass def __rand__(self, y): # real signature unknown; restored from __doc__ """ x.__rand__(y) <==> y&x """ pass def __rdivmod__(self, y): # real signature unknown; restored from __doc__ """ x.__rdivmod__(y) <==> divmod(y, x) """ pass def __rdiv__(self, y): # real signature unknown; restored from __doc__ """ x.__rdiv__(y) <==> y/x """ pass def __repr__(self): # real signature unknown; restored from __doc__ """ x.__repr__() <==> repr(x) """ pass def __rfloordiv__(self, y): # real signature unknown; restored from __doc__ """ x.__rfloordiv__(y) <==> y//x """ pass def __rlshift__(self, y): # real signature unknown; restored from __doc__ """ x.__rlshift__(y) <==> y<<x """ pass def __rmod__(self, y): # real signature unknown; restored from __doc__ """ x.__rmod__(y) <==> y%x """ pass def __rmul__(self, y): # real signature unknown; restored from __doc__ """ x.__rmul__(y) <==> y*x """ pass def __ror__(self, y): # real signature unknown; restored from __doc__ """ x.__ror__(y) <==> y|x """ pass def __rpow__(self, x, z=None): # real signature unknown; restored from __doc__ """ y.__rpow__(x[, z]) <==> pow(x, y[, z]) """ pass def __rrshift__(self, y): # real signature unknown; restored from __doc__ """ x.__rrshift__(y) <==> y>>x """ pass def __rshift__(self, y): # real signature unknown; restored from __doc__ """ x.__rshift__(y) <==> x>>y """ pass def __rsub__(self, y): # real signature unknown; restored from __doc__ """ x.__rsub__(y) <==> y-x """ pass def __rtruediv__(self, y): # real signature unknown; restored from __doc__ """ x.__rtruediv__(y) <==> y/x """ pass def __rxor__(self, y): # real signature unknown; restored from __doc__ """ x.__rxor__(y) <==> y^x """ pass def __str__(self): # real signature unknown; restored from __doc__ """ x.__str__() <==> str(x) """ pass def __sub__(self, y): # real signature unknown; restored from __doc__ """ x.__sub__(y) <==> x-y """ pass def __truediv__(self, y): # real signature unknown; restored from __doc__ """ x.__truediv__(y) <==> x/y """ pass def __trunc__(self, *args, **kwargs): # real signature unknown """ Truncating an Integral returns itself. """ pass def __xor__(self, y): # real signature unknown; restored from __doc__ """ x.__xor__(y) <==> x^y """ pass denominator = property(lambda self: object(), lambda self, v: None, lambda self: None) # default """the denominator of a rational number in lowest terms""" imag = property(lambda self: object(), lambda self, v: None, lambda self: None) # default """the imaginary part of a complex number""" numerator = property(lambda self: object(), lambda self, v: None, lambda self: None) # default """the numerator of a rational number in lowest terms""" real = property(lambda self: object(), lambda self, v: None, lambda self: None) # default """the real part of a complex number"""
常用方法已被python作为内置函数或语法堂，我们可以直接使用，但是他们的关系其实是调用的关系！
""" x.__add__(y) <==> x+y """
""" x.__sub__(y) <==> x-y """
""" x.__mul__(y) <==> x*y """
""" x.__mod__(y) <==> x%y """
""" x.__div__(y) <==> x/y """
""" x.__and__(y) <==> x&y """
""" x.__int__() <==> int(x) """
""" x.__abs__() <==> abs(x) """
""" x.__divmod__(y) <==> divmod(x, y) """
平常我们使用x+y 时，实际python内部是先创建x对象，然后调用x对象的__add__方法
二、长整型：long 类源码分析
长整数如：2147483648
class long(object): """ long(x=0) -> long long(x, base=10) -> long Convert a number or string to a long integer, or return 0L if no arguments are given. If x is floating point, the conversion truncates towards zero. If x is not a number or if base is given, then x must be a string or Unicode object representing an integer literal in the given base. The literal can be preceded by '+' or '-' and be surrounded by whitespace. The base defaults to 10. Valid bases are 0 and 2-36. Base 0 means to interpret the base from the string as an integer literal. >>> int('0b100', base=0) 4L """ def bit_length(self): # real signature unknown; restored from __doc__ """ long.bit_length() -> int or long Number of bits necessary to represent self in binary. >>> bin(37L) '0b100101' >>> (37L).bit_length() """ return 0 def conjugate(self, *args, **kwargs): # real signature unknown """ Returns self, the complex conjugate of any long. """ pass def __abs__(self): # real signature unknown; restored from __doc__ """ x.__abs__() <==> abs(x) """ pass def __add__(self, y): # real signature unknown; restored from __doc__ """ x.__add__(y) <==> x+y """ pass def __and__(self, y): # real signature unknown; restored from __doc__ """ x.__and__(y) <==> x&y """ pass def __cmp__(self, y): # real signature unknown; restored from __doc__ """ x.__cmp__(y) <==> cmp(x,y) """ pass def __coerce__(self, y): # real signature unknown; restored from __doc__ """ x.__coerce__(y) <==> coerce(x, y) """ pass def __divmod__(self, y): # real signature unknown; restored from __doc__ """ x.__divmod__(y) <==> divmod(x, y) """ pass def __div__(self, y): # real signature unknown; restored from __doc__ """ x.__div__(y) <==> x/y """ pass def __float__(self): # real signature unknown; restored from __doc__ """ x.__float__() <==> float(x) """ pass def __floordiv__(self, y): # real signature unknown; restored from __doc__ """ x.__floordiv__(y) <==> x//y """ pass def __format__(self, *args, **kwargs): # real signature unknown pass def __getattribute__(self, name): # real signature unknown; restored from __doc__ """ x.__getattribute__('name') <==> x.name """ pass def __getnewargs__(self, *args, **kwargs): # real signature unknown pass def __hash__(self): # real signature unknown; restored from __doc__ """ x.__hash__() <==> hash(x) """ pass def __hex__(self): # real signature unknown; restored from __doc__ """ x.__hex__() <==> hex(x) """ pass def __index__(self): # real signature unknown; restored from __doc__ """ x[y:z] <==> x[y.__index__():z.__index__()] """ pass def __init__(self, x=0): # real signature unknown; restored from __doc__ pass def __int__(self): # real signature unknown; restored from __doc__ """ x.__int__() <==> int(x) """ pass def __invert__(self): # real signature unknown; restored from __doc__ """ x.__invert__() <==> ~x """ pass def __long__(self): # real signature unknown; restored from __doc__ """ x.__long__() <==> long(x) """ pass def __lshift__(self, y): # real signature unknown; restored from __doc__ """ x.__lshift__(y) <==> x<<y """ pass def __mod__(self, y): # real signature unknown; restored from __doc__ """ x.__mod__(y) <==> x%y """ pass def __mul__(self, y): # real signature unknown; restored from __doc__ """ x.__mul__(y) <==> x*y """ pass def __neg__(self): # real signature unknown; restored from __doc__ """ x.__neg__() <==> -x """ pass @staticmethod # known case of __new__ def __new__(S, *more): # real signature unknown; restored from __doc__ """ T.__new__(S, ...) -> a new object with type S, a subtype of T """ pass def __nonzero__(self): # real signature unknown; restored from __doc__ """ x.__nonzero__() <==> x != 0 """ pass def __oct__(self): # real signature unknown; restored from __doc__ """ x.__oct__() <==> oct(x) """ pass def __or__(self, y): # real signature unknown; restored from __doc__ """ x.__or__(y) <==> x|y """ pass def __pos__(self): # real signature unknown; restored from __doc__ """ x.__pos__() <==> +x """ pass def __pow__(self, y, z=None): # real signature unknown; restored from __doc__ """ x.__pow__(y[, z]) <==> pow(x, y[, z]) """ pass def __radd__(self, y): # real signature unknown; restored from __doc__ """ x.__radd__(y) <==> y+x """ pass def __rand__(self, y): # real signature unknown; restored from __doc__ """ x.__rand__(y) <==> y&x """ pass def __rdivmod__(self, y): # real signature unknown; restored from __doc__ """ x.__rdivmod__(y) <==> divmod(y, x) """ pass def __rdiv__(self, y): # real signature unknown; restored from __doc__ """ x.__rdiv__(y) <==> y/x """ pass def __repr__(self): # real signature unknown; restored from __doc__ """ x.__repr__() <==> repr(x) """ pass def __rfloordiv__(self, y): # real signature unknown; restored from __doc__ """ x.__rfloordiv__(y) <==> y//x """ pass def __rlshift__(self, y): # real signature unknown; restored from __doc__ """ x.__rlshift__(y) <==> y<<x """ pass def __rmod__(self, y): # real signature unknown; restored from __doc__ """ x.__rmod__(y) <==> y%x """ pass def __rmul__(self, y): # real signature unknown; restored from __doc__ """ x.__rmul__(y) <==> y*x """ pass def __ror__(self, y): # real signature unknown; restored from __doc__ """ x.__ror__(y) <==> y|x """ pass def __rpow__(self, x, z=None): # real signature unknown; restored from __doc__ """ y.__rpow__(x[, z]) <==> pow(x, y[, z]) """ pass def __rrshift__(self, y): # real signature unknown; restored from __doc__ """ x.__rrshift__(y) <==> y>>x """ pass def __rshift__(self, y): # real signature unknown; restored from __doc__ """ x.__rshift__(y) <==> x>>y """ pass def __rsub__(self, y): # real signature unknown; restored from __doc__ """ x.__rsub__(y) <==> y-x """ pass def __rtruediv__(self, y): # real signature unknown; restored from __doc__ """ x.__rtruediv__(y) <==> y/x """ pass def __rxor__(self, y): # real signature unknown; restored from __doc__ """ x.__rxor__(y) <==> y^x """ pass def __sizeof__(self, *args, **kwargs): # real signature unknown """ Returns size in memory, in bytes """ pass def __str__(self): # real signature unknown; restored from __doc__ """ x.__str__() <==> str(x) """ pass def __sub__(self, y): # real signature unknown; restored from __doc__ """ x.__sub__(y) <==> x-y """ pass def __truediv__(self, y): # real signature unknown; restored from __doc__ """ x.__truediv__(y) <==> x/y """ pass def __trunc__(self, *args, **kwargs): # real signature unknown """ Truncating an Integral returns itself. """ pass def __xor__(self, y): # real signature unknown; restored from __doc__ """ x.__xor__(y) <==> x^y """ pass denominator = property(lambda self: object(), lambda self, v: None, lambda self: None) # default """the denominator of a rational number in lowest terms""" imag = property(lambda self: object(), lambda self, v: None, lambda self: None) # default """the imaginary part of a complex number""" numerator = property(lambda self: object(), lambda self, v: None, lambda self: None) # default """the numerator of a rational number in lowest terms""" real = property(lambda self: object(), lambda self, v: None, lambda self: None) # default """the real part of a complex number""" long
long 与 int 基本是相同的，只是长度不一样而已，在python 3中，没有了long类型，只保留了int类型。
三、浮点型：float 类源码分析
浮点型如：1.0
class float(object): """ float(x) -> floating point number Convert a string or number to a floating point number, if possible. """ def as_integer_ratio(self): """ 获取改值的最简比 """ """ float.as_integer_ratio() -> (int, int) Return a pair of integers, whose ratio is exactly equal to the original float and with a positive denominator. Raise OverflowError on infinities and a ValueError on NaNs. >>> (10.0).as_integer_ratio() (10, 1) >>> (0.0).as_integer_ratio() (0, 1) >>> (-.25).as_integer_ratio() (-1, 4) """ pass def conjugate(self, *args, **kwargs): # real signature unknown """ Return self, the complex conjugate of any float. """ pass def fromhex(self, string): """ 将十六进制字符串转换成浮点型 """ """ float.fromhex(string) -> float Create a floating-point number from a hexadecimal string. >>> float.fromhex('0x1.ffffp10') 2047.984375 >>> float.fromhex('-0x1p-1074') -4.9406564584124654e-324 """ return 0.0 def hex(self): """ 返回当前值的 16 进制表示 """ """ float.hex() -> string Return a hexadecimal representation of a floating-point number. >>> (-0.1).hex() '-0x1.999999999999ap-4' >>> 3.14159.hex() '0x1.921f9f01b866ep+1' """ return "" def is_integer(self, *args, **kwargs): # real signature unknown """ Return True if the float is an integer. """ pass def __abs__(self): """ x.__abs__() <==> abs(x) """ pass def __add__(self, y): """ x.__add__(y) <==> x+y """ pass def __coerce__(self, y): """ x.__coerce__(y) <==> coerce(x, y) """ pass def __divmod__(self, y): """ x.__divmod__(y) <==> divmod(x, y) """ pass def __div__(self, y): """ x.__div__(y) <==> x/y """ pass def __eq__(self, y): """ x.__eq__(y) <==> x==y """ pass def __float__(self): """ x.__float__() <==> float(x) """ pass def __floordiv__(self, y): """ x.__floordiv__(y) <==> x//y """ pass def __format__(self, format_spec): """ float.__format__(format_spec) -> string Formats the float according to format_spec. """ return "" def __getattribute__(self, name): """ x.__getattribute__('name') <==> x.name """ pass def __getformat__(self, typestr): """ float.__getformat__(typestr) -> string You probably don't want to use this function. It exists mainly to be used in Python's test suite. typestr must be 'double' or 'float'. This function returns whichever of 'unknown', 'IEEE, big-endian' or 'IEEE, little-endian' best describes the format of floating point numbers used by the C type named by typestr. """ return "" def __getnewargs__(self, *args, **kwargs): # real signature unknown pass def __ge__(self, y): """ x.__ge__(y) <==> x>=y """ pass def __gt__(self, y): """ x.__gt__(y) <==> x>y """ pass def __hash__(self): """ x.__hash__() <==> hash(x) """ pass def __init__(self, x): pass def __int__(self): """ x.__int__() <==> int(x) """ pass def __le__(self, y): """ x.__le__(y) <==> x<=y """ pass def __long__(self): """ x.__long__() <==> long(x) """ pass def __lt__(self, y): """ x.__lt__(y) <==> x<y """ pass def __mod__(self, y): """ x.__mod__(y) <==> x%y """ pass def __mul__(self, y): """ x.__mul__(y) <==> x*y """ pass def __neg__(self): """ x.__neg__() <==> -x """ pass @staticmethod # known case of __new__ def __new__(S, *more): """ T.__new__(S, ...) -> a new object with type S, a subtype of T """ pass def __ne__(self, y): """ x.__ne__(y) <==> x!=y """ pass def __nonzero__(self): """ x.__nonzero__() <==> x != 0 """ pass def __pos__(self): """ x.__pos__() <==> +x """ pass def __pow__(self, y, z=None): """ x.__pow__(y[, z]) <==> pow(x, y[, z]) """ pass def __radd__(self, y): """ x.__radd__(y) <==> y+x """ pass def __rdivmod__(self, y): """ x.__rdivmod__(y) <==> divmod(y, x) """ pass def __rdiv__(self, y): """ x.__rdiv__(y) <==> y/x """ pass def __repr__(self): """ x.__repr__() <==> repr(x) """ pass def __rfloordiv__(self, y): """ x.__rfloordiv__(y) <==> y//x """ pass def __rmod__(self, y): """ x.__rmod__(y) <==> y%x """ pass def __rmul__(self, y): """ x.__rmul__(y) <==> y*x """ pass def __rpow__(self, x, z=None): """ y.__rpow__(x[, z]) <==> pow(x, y[, z]) """ pass def __rsub__(self, y): """ x.__rsub__(y) <==> y-x """ pass def __rtruediv__(self, y): """ x.__rtruediv__(y) <==> y/x """ pass def __setformat__(self, typestr, fmt): """ float.__setformat__(typestr, fmt) -> None You probably don't want to use this function. It exists mainly to be used in Python's test suite. typestr must be 'double' or 'float'. fmt must be one of 'unknown', 'IEEE, big-endian' or 'IEEE, little-endian', and in addition can only be one of the latter two if it appears to match the underlying C reality. Override the automatic determination of C-level floating point type. This affects how floats are converted to and from binary strings. """ pass def __str__(self): """ x.__str__() <==> str(x) """ pass def __sub__(self, y): """ x.__sub__(y) <==> x-y """ pass def __truediv__(self, y): """ x.__truediv__(y) <==> x/y """ pass def __trunc__(self, *args, **kwargs): # real signature unknown """ Return the Integral closest to x between 0 and x. """ pass imag = property(lambda self: object(), lambda self, v: None, lambda self: None) # default """the imaginary part of a complex number""" real = property(lambda self: object(), lambda self, v: None, lambda self: None) # default """the real part of a complex number""" float
四、字符串：str 类源码分析
字符串如：'Hello World!' , "Hello Python!"
class str(basestring): """ str(object='') -> string Return a nice string representation of the object. If the argument is a string, the return value is the same object. """ def capitalize(self): """ 首字母变大写 """ """ S.capitalize() -> string Return a copy of the string S with only its first character capitalized. """ return "" def center(self, width, fillchar=None): """ 内容居中，width：总长度；fillchar：空白处填充内容，默认无 """ """ S.center(width[, fillchar]) -> string Return S centered in a string of length width. Padding is done using the specified fill character (default is a space) """ return "" def count(self, sub, start=None, end=None): """ 子序列个数 """ """ S.count(sub[, start[, end]]) -> int Return the number of non-overlapping occurrences of substring sub in string S[start:end]. Optional arguments start and end are interpreted as in slice notation. """ return 0 def decode(self, encoding=None, errors=None): """ 解码 """ """ S.decode([encoding[,errors]]) -> object Decodes S using the codec registered for encoding. encoding defaults to the default encoding. errors may be given to set a different error handling scheme. Default is 'strict' meaning that encoding errors raise a UnicodeDecodeError. Other possible values are 'ignore' and 'replace' as well as any other name registered with codecs.register_error that is able to handle UnicodeDecodeErrors. """ return object() def encode(self, encoding=None, errors=None): """ 编码，针对unicode """ """ S.encode([encoding[,errors]]) -> object Encodes S using the codec registered for encoding. encoding defaults to the default encoding. errors may be given to set a different error handling scheme. Default is 'strict' meaning that encoding errors raise a UnicodeEncodeError. Other possible values are 'ignore', 'replace' and 'xmlcharrefreplace' as well as any other name registered with codecs.register_error that is able to handle UnicodeEncodeErrors. """ return object() def endswith(self, suffix, start=None, end=None): """ 是否以 xxx 结束 """ """ S.endswith(suffix[, start[, end]]) -> bool Return True if S ends with the specified suffix, False otherwise. With optional start, test S beginning at that position. With optional end, stop comparing S at that position. suffix can also be a tuple of strings to try. """ return False def expandtabs(self, tabsize=None): """ 将tab转换成空格，默认一个tab转换成8个空格 """ """ S.expandtabs([tabsize]) -> string Return a copy of S where all tab characters are expanded using spaces. If tabsize is not given, a tab size of 8 characters is assumed. """ return "" def find(self, sub, start=None, end=None): """ 寻找子序列位置，如果没找到，返回 -1 """ """ S.find(sub [,start [,end]]) -> int Return the lowest index in S where substring sub is found, such that sub is contained within S[start:end]. Optional arguments start and end are interpreted as in slice notation. Return -1 on failure. """ return 0 def format(*args, **kwargs): # known special case of str.format """ 字符串格式化，动态参数，将函数式编程时细说 """ """ S.format(*args, **kwargs) -> string Return a formatted version of S, using substitutions from args and kwargs. The substitutions are identified by braces ('{' and '}'). """ pass def index(self, sub, start=None, end=None): """ 子序列位置，如果没找到，报错 """ S.index(sub [,start [,end]]) -> int Like S.find() but raise ValueError when the substring is not found. """ return 0 def isalnum(self): """ 是否是字母和数字 """ """ S.isalnum() -> bool Return True if all characters in S are alphanumeric and there is at least one character in S, False otherwise. """ return False def isalpha(self): """ 是否是字母 """ """ S.isalpha() -> bool Return True if all characters in S are alphabetic and there is at least one character in S, False otherwise. """ return False def isdigit(self): """ 是否是数字 """ """ S.isdigit() -> bool Return True if all characters in S are digits and there is at least one character in S, False otherwise. """ return False def islower(self): """ 是否小写 """ """ S.islower() -> bool Return True if all cased characters in S are lowercase and there is at least one cased character in S, False otherwise. """ return False def isspace(self): """ S.isspace() -> bool Return True if all characters in S are whitespace and there is at least one character in S, False otherwise. """ return False def istitle(self): """ S.istitle() -> bool Return True if S is a titlecased string and there is at least one character in S, i.e. uppercase characters may only follow uncased characters and lowercase characters only cased ones. Return False otherwise. """ return False def isupper(self): """ S.isupper() -> bool Return True if all cased characters in S are uppercase and there is at least one cased character in S, False otherwise. """ return False def join(self, iterable): """ 连接 """ """ S.join(iterable) -> string Return a string which is the concatenation of the strings in the iterable. The separator between elements is S. """ return "" def ljust(self, width, fillchar=None): """ 内容左对齐，右侧填充 """ """ S.ljust(width[, fillchar]) -> string Return S left-justified in a string of length width. Padding is done using the specified fill character (default is a space). """ return "" def lower(self): """ 变小写 """ """ S.lower() -> string Return a copy of the string S converted to lowercase. """ return "" def lstrip(self, chars=None): """ 移除左侧空白 """ """ S.lstrip([chars]) -> string or unicode Return a copy of the string S with leading whitespace removed. If chars is given and not None, remove characters in chars instead. If chars is unicode, S will be converted to unicode before stripping """ return "" def partition(self, sep): """ 分割，前，中，后三部分 """ """ S.partition(sep) -> (head, sep, tail) Search for the separator sep in S, and return the part before it, the separator itself, and the part after it. If the separator is not found, return S and two empty strings. """ pass def replace(self, old, new, count=None): """ 替换 """ """ S.replace(old, new[, count]) -> string Return a copy of string S with all occurrences of substring old replaced by new. If the optional argument count is given, only the first count occurrences are replaced. """ return "" def rfind(self, sub, start=None, end=None): """ S.rfind(sub [,start [,end]]) -> int Return the highest index in S where substring sub is found, such that sub is contained within S[start:end]. Optional arguments start and end are interpreted as in slice notation. Return -1 on failure. """ return 0 def rindex(self, sub, start=None, end=None): """ S.rindex(sub [,start [,end]]) -> int Like S.rfind() but raise ValueError when the substring is not found. """ return 0 def rjust(self, width, fillchar=None): """ S.rjust(width[, fillchar]) -> string Return S right-justified in a string of length width. Padding is done using the specified fill character (default is a space) """ return "" def rpartition(self, sep): """ S.rpartition(sep) -> (head, sep, tail) Search for the separator sep in S, starting at the end of S, and return the part before it, the separator itself, and the part after it. If the separator is not found, return two empty strings and S. """ pass def rsplit(self, sep=None, maxsplit=None): """ S.rsplit([sep [,maxsplit]]) -> list of strings Return a list of the words in the string S, using sep as the delimiter string, starting at the end of the string and working to the front. If maxsplit is given, at most maxsplit splits are done. If sep is not specified or is None, any whitespace string is a separator. """ return [] def rstrip(self, chars=None): """ S.rstrip([chars]) -> string or unicode Return a copy of the string S with trailing whitespace removed. If chars is given and not None, remove characters in chars instead. If chars is unicode, S will be converted to unicode before stripping """ return "" def split(self, sep=None, maxsplit=None): """ 分割， maxsplit最多分割几次 """ """ S.split([sep [,maxsplit]]) -> list of strings Return a list of the words in the string S, using sep as the delimiter string. If maxsplit is given, at most maxsplit splits are done. If sep is not specified or is None, any whitespace string is a separator and empty strings are removed from the result. """ return [] def splitlines(self, keepends=False): """ 根据换行分割 """ """ S.splitlines(keepends=False) -> list of strings Return a list of the lines in S, breaking at line boundaries. Line breaks are not included in the resulting list unless keepends is given and true. """ return [] def startswith(self, prefix, start=None, end=None): """ 是否起始 """ """ S.startswith(prefix[, start[, end]]) -> bool Return True if S starts with the specified prefix, False otherwise. With optional start, test S beginning at that position. With optional end, stop comparing S at that position. prefix can also be a tuple of strings to try. """ return False def strip(self, chars=None): """ 移除两段空白 """ """ S.strip([chars]) -> string or unicode Return a copy of the string S with leading and trailing whitespace removed. If chars is given and not None, remove characters in chars instead. If chars is unicode, S will be converted to unicode before stripping """ return "" def swapcase(self): """ 大写变小写，小写变大写 """ """ S.swapcase() -> string Return a copy of the string S with uppercase characters converted to lowercase and vice versa. """ return "" def title(self): """ S.title() -> string Return a titlecased version of S, i.e. words start with uppercase characters, all remaining cased characters have lowercase. """ return "" def translate(self, table, deletechars=None): """ 转换，需要先做一个对应表，最后一个表示删除字符集合 intab = "aeiou" outtab = "12345" trantab = maketrans(intab, outtab) str = "this is string example....wow!!!" print str.translate(trantab, 'xm') """ """ S.translate(table [,deletechars]) -> string Return a copy of the string S, where all characters occurring in the optional argument deletechars are removed, and the remaining characters have been mapped through the given translation table, which must be a string of length 256 or None. If the table argument is None, no translation is applied and the operation simply removes the characters in deletechars. """ return "" def upper(self): """ S.upper() -> string Return a copy of the string S converted to uppercase. """ return "" def zfill(self, width): """方法返回指定长度的字符串，原字符串右对齐，前面填充0。""" """ S.zfill(width) -> string Pad a numeric string S with zeros on the left, to fill a field of the specified width. The string S is never truncated. """ return "" def _formatter_field_name_split(self, *args, **kwargs): # real signature unknown pass def _formatter_parser(self, *args, **kwargs): # real signature unknown pass def __add__(self, y): """ x.__add__(y) <==> x+y """ pass def __contains__(self, y): """ x.__contains__(y) <==> y in x """ pass def __eq__(self, y): """ x.__eq__(y) <==> x==y """ pass def __format__(self, format_spec): """ S.__format__(format_spec) -> string Return a formatted version of S as described by format_spec. """ return "" def __getattribute__(self, name): """ x.__getattribute__('name') <==> x.name """ pass def __getitem__(self, y): """ x.__getitem__(y) <==> x[y] """ pass def __getnewargs__(self, *args, **kwargs): # real signature unknown pass def __getslice__(self, i, j): """ x.__getslice__(i, j) <==> x[i:j] Use of negative indices is not supported. """ pass def __ge__(self, y): """ x.__ge__(y) <==> x>=y """ pass def __gt__(self, y): """ x.__gt__(y) <==> x>y """ pass def __hash__(self): """ x.__hash__() <==> hash(x) """ pass def __init__(self, string=''): # known special case of str.__init__ """ str(object='') -> string Return a nice string representation of the object. If the argument is a string, the return value is the same object. # (copied from class doc) """ pass def __len__(self): """ x.__len__() <==> len(x) """ pass def __le__(self, y): """ x.__le__(y) <==> x<=y """ pass def __lt__(self, y): """ x.__lt__(y) <==> x<y """ pass def __mod__(self, y): """ x.__mod__(y) <==> x%y """ pass def __mul__(self, n): """ x.__mul__(n) <==> x*n """ pass @staticmethod # known case of __new__ def __new__(S, *more): """ T.__new__(S, ...) -> a new object with type S, a subtype of T """ pass def __ne__(self, y): """ x.__ne__(y) <==> x!=y """ pass def __repr__(self): """ x.__repr__() <==> repr(x) """ pass def __rmod__(self, y): """ x.__rmod__(y) <==> y%x """ pass def __rmul__(self, n): """ x.__rmul__(n) <==> n*x """ pass def __sizeof__(self): """ S.__sizeof__() -> size of S in memory, in bytes """ pass def __str__(self): """ x.__str__() <==> str(x) """ pass str
字符串在任何一门语言中，都是重点。程序处理字符串的情况，是最为频繁的，以下具体实例分析加深理解
#!/usr/bin/env python # -*- coding: utf-8 -*- s1 = " Hello word! " print(dir(s1))
使用dir() 输出对象所拥有的所有成员，如下：
['__add__', '__class__', '__contains__', '__delattr__', '__doc__', '__eq__', '__format__', '__ge__', '__getattribute__', '__getitem__', '__getnewargs__', '__getslice__', '__gt__', '__hash__', '__init__', '__le__', '__len__', '__lt__', '__mod__', '__mul__', '__ne__', '__new__', '__reduce__', '__reduce_ex__', '__repr__', '__rmod__', '__rmul__', '__setattr__', '__sizeof__', '__str__', '__subclasshook__', '_formatter_field_name_split', '_formatter_parser', 'capitalize', 'center', 'count', 'decode', 'encode', 'endswith', 'expandtabs', 'find', 'format', 'index', 'isalnum', 'isalpha', 'isdigit', 'islower', 'isspace', 'istitle', 'isupper', 'join', 'ljust', 'lower', 'lstrip', 'partition', 'replace', 'rfind', 'rindex', 'rjust', 'rpartition', 'rsplit', 'rstrip', 'split', 'splitlines', 'startswith', 'strip', 'swapcase', 'title', 'translate', 'upper', 'zfill']
使用help() 查询函数使用文档，如
>>> help(s1.capitalize)
Help on built-in function capitalize:
capitalize(...)
S.capitalize() -> string
Return a copy of the string S with only its first character
capitalized.
根据帮助信息可知，S.capitalize() 返回一个字符串类型，是原字符串的一个拷贝，其中首字母改变为大写。
>>> s1="hello,world" >>> s1.capitalize() 'Hello,world'
使用同样的学习分析方法，分析字符串其他内置函数的使用。
S.join(iterable) -> string ： 返回一个字符串类型，用S将一个可迭代对象拼接成一个字符串
>>> alist=["Hello","world"] >>> " ".join(alist) 'Hello world' >>> "&".join(alist) 'Hello&world' >>> "-".join(alist) 'Hello-world'
S.partition(sep) -> (head, sep, tail)：分割一个字符串，返回一个元组(前，中，后)
>>> s1="http://www.baidu.com"
>>> s1.partition("//")
('http:', '//', 'www.baidu.com')
>>>
S.split([sep [,maxsplit]]) -> list of strings ：分割一个字符串，返回一个列表
>>> s1="http://www.baidu.com"
>>> s1.split("//")
['http:', 'www.baidu.com']
S.splitlines(keepends=False) -> list of strings：根据换行分割，返回一个列表
>>> s1="Hello \n Dear Milton" >>> s1.split() ['Hello', 'Dear', 'Milton'] >>> s1.splitlines() ['Hello ', ' Dear Milton'] >>>
S.strip([chars]) -> string or unicode ：移除字符串两端空白字符
>>> s1=" Hello,world! " >>> s1.strip() 'Hello,world!' >>>
S.replace(old, new[, count]) -> string : 替换字符
>>> s1
'Hello \n Dear Milton'
>>> s1.replace("Milton","Cherish")
'Hello \n Dear Cherish'
>>>
五、列表：list 类源码分析
列表如：["Hello","Python"] , [1,2,3]
class list(object): """ list() -> new empty list list(iterable) -> new list initialized from iterable's items """ def append(self, p_object): # real signature unknown; restored from __doc__ """ L.append(object) -- append object to end """ pass def count(self, value): # real signature unknown; restored from __doc__ """ L.count(value) -> integer -- return number of occurrences of value """ return 0 def extend(self, iterable): # real signature unknown; restored from __doc__ """ L.extend(iterable) -- extend list by appending elements from the iterable """ pass def index(self, value, start=None, stop=None): # real signature unknown; restored from __doc__ """ L.index(value, [start, [stop]]) -> integer -- return first index of value. Raises ValueError if the value is not present. """ return 0 def insert(self, index, p_object): # real signature unknown; restored from __doc__ """ L.insert(index, object) -- insert object before index """ pass def pop(self, index=None): # real signature unknown; restored from __doc__ """ L.pop([index]) -> item -- remove and return item at index (default last). Raises IndexError if list is empty or index is out of range. """ pass def remove(self, value): # real signature unknown; restored from __doc__ """ L.remove(value) -- remove first occurrence of value. Raises ValueError if the value is not present. """ pass def reverse(self): # real signature unknown; restored from __doc__ """ L.reverse() -- reverse *IN PLACE* """ pass def sort(self, cmp=None, key=None, reverse=False): # real signature unknown; restored from __doc__ """ L.sort(cmp=None, key=None, reverse=False) -- stable sort *IN PLACE*; cmp(x, y) -> -1, 0, 1 """ pass def __add__(self, y): # real signature unknown; restored from __doc__ """ x.__add__(y) <==> x+y """ pass def __contains__(self, y): # real signature unknown; restored from __doc__ """ x.__contains__(y) <==> y in x """ pass def __delitem__(self, y): # real signature unknown; restored from __doc__ """ x.__delitem__(y) <==> del x[y] """ pass def __delslice__(self, i, j): # real signature unknown; restored from __doc__ """ x.__delslice__(i, j) <==> del x[i:j] Use of negative indices is not supported. """ pass def __eq__(self, y): # real signature unknown; restored from __doc__ """ x.__eq__(y) <==> x==y """ pass def __getattribute__(self, name): # real signature unknown; restored from __doc__ """ x.__getattribute__('name') <==> x.name """ pass def __getitem__(self, y): # real signature unknown; restored from __doc__ """ x.__getitem__(y) <==> x[y] """ pass def __getslice__(self, i, j): # real signature unknown; restored from __doc__ """ x.__getslice__(i, j) <==> x[i:j] Use of negative indices is not supported. """ pass def __ge__(self, y): # real signature unknown; restored from __doc__ """ x.__ge__(y) <==> x>=y """ pass def __gt__(self, y): # real signature unknown; restored from __doc__ """ x.__gt__(y) <==> x>y """ pass def __iadd__(self, y): # real signature unknown; restored from __doc__ """ x.__iadd__(y) <==> x+=y """ pass def __imul__(self, y): # real signature unknown; restored from __doc__ """ x.__imul__(y) <==> x*=y """ pass def __init__(self, seq=()): # known special case of list.__init__ """ list() -> new empty list list(iterable) -> new list initialized from iterable's items # (copied from class doc) """ pass def __iter__(self): # real signature unknown; restored from __doc__ """ x.__iter__() <==> iter(x) """ pass def __len__(self): # real signature unknown; restored from __doc__ """ x.__len__() <==> len(x) """ pass def __le__(self, y): # real signature unknown; restored from __doc__ """ x.__le__(y) <==> x<=y """ pass def __lt__(self, y): # real signature unknown; restored from __doc__ """ x.__lt__(y) <==> x<y """ pass def __mul__(self, n): # real signature unknown; restored from __doc__ """ x.__mul__(n) <==> x*n """ pass @staticmethod # known case of __new__ def __new__(S, *more): # real signature unknown; restored from __doc__ """ T.__new__(S, ...) -> a new object with type S, a subtype of T """ pass def __ne__(self, y): # real signature unknown; restored from __doc__ """ x.__ne__(y) <==> x!=y """ pass def __repr__(self): # real signature unknown; restored from __doc__ """ x.__repr__() <==> repr(x) """ pass def __reversed__(self): # real signature unknown; restored from __doc__ """ L.__reversed__() -- return a reverse iterator over the list """ pass def __rmul__(self, n): # real signature unknown; restored from __doc__ """ x.__rmul__(n) <==> n*x """ pass def __setitem__(self, i, y): # real signature unknown; restored from __doc__ """ x.__setitem__(i, y) <==> x[i]=y """ pass def __setslice__(self, i, j, y): # real signature unknown; restored from __doc__ """ x.__setslice__(i, j, y) <==> x[i:j]=y Use of negative indices is not supported. """ pass def __sizeof__(self): # real signature unknown; restored from __doc__ """ L.__sizeof__() -- size of L in memory, in bytes """ pass __hash__ = None list
list列表实例：
>>> alist=["I","Love","Cherish"]
>>> alist.append("Forever")
>>> alist
['I', 'Love', 'Cherish', 'Forever']
>>> alist.pop()
'Forever'
>>> alist
['I', 'Love', 'Cherish']
>>> alist.extend(["forever","and","always"])
>>> alist
['I', 'Love', 'Cherish', 'forever', 'and', 'always']
>>> alist.count("and")
1
>>> alist.index("and")
4
>>> alist.insert(3,"Yangp")
>>> alist
['I', 'Love', 'Cherish', 'Yangp', 'forever', 'and', 'always']
>>> alist.remove("always")
>>> alist
['I', 'Love', 'Cherish', 'Yangp', 'forever', 'and']
>>> blist=[1,3,2,0,5]
>>> blist.sort()
>>> blist
[0, 1, 2, 3, 5]
>>> blist.reverse()
>>> blist
[5, 3, 2, 1, 0]
>>>
六、元组：tuple 类源码分析
元组如：("Hello",""World") , (1,2,3)
class tuple(object): """ tuple() -> empty tuple tuple(iterable) -> tuple initialized from iterable's items If the argument is a tuple, the return value is the same object. """ def count(self, value): # real signature unknown; restored from __doc__ """ T.count(value) -> integer -- return number of occurrences of value """ return 0 def index(self, value, start=None, stop=None): # real signature unknown; restored from __doc__ """ T.index(value, [start, [stop]]) -> integer -- return first index of value. Raises ValueError if the value is not present. """ return 0 def __add__(self, y): # real signature unknown; restored from __doc__ """ x.__add__(y) <==> x+y """ pass def __contains__(self, y): # real signature unknown; restored from __doc__ """ x.__contains__(y) <==> y in x """ pass def __eq__(self, y): # real signature unknown; restored from __doc__ """ x.__eq__(y) <==> x==y """ pass def __getattribute__(self, name): # real signature unknown; restored from __doc__ """ x.__getattribute__('name') <==> x.name """ pass def __getitem__(self, y): # real signature unknown; restored from __doc__ """ x.__getitem__(y) <==> x[y] """ pass def __getnewargs__(self, *args, **kwargs): # real signature unknown pass def __getslice__(self, i, j): # real signature unknown; restored from __doc__ """ x.__getslice__(i, j) <==> x[i:j] Use of negative indices is not supported. """ pass def __ge__(self, y): # real signature unknown; restored from __doc__ """ x.__ge__(y) <==> x>=y """ pass def __gt__(self, y): # real signature unknown; restored from __doc__ """ x.__gt__(y) <==> x>y """ pass def __hash__(self): # real signature unknown; restored from __doc__ """ x.__hash__() <==> hash(x) """ pass def __init__(self, seq=()): # known special case of tuple.__init__ """ tuple() -> empty tuple tuple(iterable) -> tuple initialized from iterable's items If the argument is a tuple, the return value is the same object. # (copied from class doc) """ pass def __iter__(self): # real signature unknown; restored from __doc__ """ x.__iter__() <==> iter(x) """ pass def __len__(self): # real signature unknown; restored from __doc__ """ x.__len__() <==> len(x) """ pass def __le__(self, y): # real signature unknown; restored from __doc__ """ x.__le__(y) <==> x<=y """ pass def __lt__(self, y): # real signature unknown; restored from __doc__ """ x.__lt__(y) <==> x<y """ pass def __mul__(self, n): # real signature unknown; restored from __doc__ """ x.__mul__(n) <==> x*n """ pass @staticmethod # known case of __new__ def __new__(S, *more): # real signature unknown; restored from __doc__ """ T.__new__(S, ...) -> a new object with type S, a subtype of T """ pass def __ne__(self, y): # real signature unknown; restored from __doc__ """ x.__ne__(y) <==> x!=y """ pass def __repr__(self): # real signature unknown; restored from __doc__ """ x.__repr__() <==> repr(x) """ pass def __rmul__(self, n): # real signature unknown; restored from __doc__ """ x.__rmul__(n) <==> n*x """ pass def __sizeof__(self): # real signature unknown; restored from __doc__ """ T.__sizeof__() -- size of T in memory, in bytes """ pass tuple
由于元组是不可修改类型，相比列表，它所拥有的方法少了很多。
>>> t1=("Hello","World","Hello")
>>> dir(t1)
['__add__', '__class__', '__contains__', '__delattr__', '__doc__', '__eq__', '__format__', '__ge__', '__getattribute__',
'__getitem__', '__getnewargs__', '__getslice__', '__gt__', '__hash__', '__init__', '__iter__', '__le__', '__len__', '__
lt__', '__mul__', '__ne__', '__new__', '__reduce__', '__reduce_ex__', '__repr__', '__rmul__', '__setattr__', '__sizeof__
', '__str__', '__subclasshook__', 'count', 'index']
>>> t1=("Hello","World","Hello")
>>> t1.count("Hello")
2
>>> t1.index("World")
1
七、字典：dict 类源码分析
字典如: {'name':'Milton','age':28}
字典是无序的key-value键值对，不能通过顺序（索引）取值，可以通过key获得对应的value值。
class dict(object): """ dict() -> new empty dictionary dict(mapping) -> new dictionary initialized from a mapping object's (key, value) pairs dict(iterable) -> new dictionary initialized as if via: d = {} for k, v in iterable: d[k] = v dict(**kwargs) -> new dictionary initialized with the name=value pairs in the keyword argument list. For example: dict(one=1, two=2) """ def clear(self): # real signature unknown; restored from __doc__ """ 清除内容 """ """ D.clear() -> None. Remove all items from D. """ pass def copy(self): # real signature unknown; restored from __doc__ """ 浅拷贝 """ """ D.copy() -> a shallow copy of D """ pass @staticmethod # known case def fromkeys(S, v=None): # real signature unknown; restored from __doc__ """ dict.fromkeys(S[,v]) -> New dict with keys from S and values equal to v. v defaults to None. """ pass def get(self, k, d=None): # real signature unknown; restored from __doc__ """ 根据key获取值，d是默认值 """ """ D.get(k[,d]) -> D[k] if k in D, else d. d defaults to None. """ pass def has_key(self, k): # real signature unknown; restored from __doc__ """ 是否有key """ """ D.has_key(k) -> True if D has a key k, else False """ return False def items(self): # real signature unknown; restored from __doc__ """ 所有项的列表形式 """ """ D.items() -> list of D's (key, value) pairs, as 2-tuples """ return [] def iteritems(self): # real signature unknown; restored from __doc__ """ 项可迭代 """ """ D.iteritems() -> an iterator over the (key, value) items of D """ pass def iterkeys(self): # real signature unknown; restored from __doc__ """ key可迭代 """ """ D.iterkeys() -> an iterator over the keys of D """ pass def itervalues(self): # real signature unknown; restored from __doc__ """ value可迭代 """ """ D.itervalues() -> an iterator over the values of D """ pass def keys(self): # real signature unknown; restored from __doc__ """ 所有的key列表 """ """ D.keys() -> list of D's keys """ return [] def pop(self, k, d=None): # real signature unknown; restored from __doc__ """ 获取并在字典中移除 """ """ D.pop(k[,d]) -> v, remove specified key and return the corresponding value. If key is not found, d is returned if given, otherwise KeyError is raised """ pass def popitem(self): # real signature unknown; restored from __doc__ """ 获取并在字典中移除 """ """ D.popitem() -> (k, v), remove and return some (key, value) pair as a 2-tuple; but raise KeyError if D is empty. """ pass def setdefault(self, k, d=None): # real signature unknown; restored from __doc__ """ 如果key不存在，则创建，如果存在，则返回已存在的值且不修改 """ """ D.setdefault(k[,d]) -> D.get(k,d), also set D[k]=d if k not in D """ pass def update(self, E=None, **F): # known special case of dict.update """ 更新 {'name':'alex', 'age': 18000} [('name','sbsbsb'),] """ """ D.update([E, ]**F) -> None. Update D from dict/iterable E and F. If E present and has a .keys() method, does: for k in E: D[k] = E[k] If E present and lacks .keys() method, does: for (k, v) in E: D[k] = v In either case, this is followed by: for k in F: D[k] = F[k] """ pass def values(self): # real signature unknown; restored from __doc__ """ 所有的值 """ """ D.values() -> list of D's values """ return [] def viewitems(self): # real signature unknown; restored from __doc__ """ 所有项，只是将内容保存至view对象中 """ """ D.viewitems() -> a set-like object providing a view on D's items """ pass def viewkeys(self): # real signature unknown; restored from __doc__ """ D.viewkeys() -> a set-like object providing a view on D's keys """ pass def viewvalues(self): # real signature unknown; restored from __doc__ """ D.viewvalues() -> an object providing a view on D's values """ pass def __cmp__(self, y): # real signature unknown; restored from __doc__ """ x.__cmp__(y) <==> cmp(x,y) """ pass def __contains__(self, k): # real signature unknown; restored from __doc__ """ D.__contains__(k) -> True if D has a key k, else False """ return False def __delitem__(self, y): # real signature unknown; restored from __doc__ """ x.__delitem__(y) <==> del x[y] """ pass def __eq__(self, y): # real signature unknown; restored from __doc__ """ x.__eq__(y) <==> x==y """ pass def __getattribute__(self, name): # real signature unknown; restored from __doc__ """ x.__getattribute__('name') <==> x.name """ pass def __getitem__(self, y): # real signature unknown; restored from __doc__ """ x.__getitem__(y) <==> x[y] """ pass def __ge__(self, y): # real signature unknown; restored from __doc__ """ x.__ge__(y) <==> x>=y """ pass def __gt__(self, y): # real signature unknown; restored from __doc__ """ x.__gt__(y) <==> x>y """ pass def __init__(self, seq=None, **kwargs): # known special case of dict.__init__ """ dict() -> new empty dictionary dict(mapping) -> new dictionary initialized from a mapping object's (key, value) pairs dict(iterable) -> new dictionary initialized as if via: d = {} for k, v in iterable: d[k] = v dict(**kwargs) -> new dictionary initialized with the name=value pairs in the keyword argument list. For example: dict(one=1, two=2) # (copied from class doc) """ pass def __iter__(self): # real signature unknown; restored from __doc__ """ x.__iter__() <==> iter(x) """ pass def __len__(self): # real signature unknown; restored from __doc__ """ x.__len__() <==> len(x) """ pass def __le__(self, y): # real signature unknown; restored from __doc__ """ x.__le__(y) <==> x<=y """ pass def __lt__(self, y): # real signature unknown; restored from __doc__ """ x.__lt__(y) <==> x<y """ pass @staticmethod # known case of __new__ def __new__(S, *more): # real signature unknown; restored from __doc__ """ T.__new__(S, ...) -> a new object with type S, a subtype of T """ pass def __ne__(self, y): # real signature unknown; restored from __doc__ """ x.__ne__(y) <==> x!=y """ pass def __repr__(self): # real signature unknown; restored from __doc__ """ x.__repr__() <==> repr(x) """ pass def __setitem__(self, i, y): # real signature unknown; restored from __doc__ """ x.__setitem__(i, y) <==> x[i]=y """ pass def __sizeof__(self): # real signature unknown; restored from __doc__ """ D.__sizeof__() -> size of D in memory, in bytes """ pass __hash__ = None dict
创建字典方式有：
>>> d1={'name':'Milton','age':28}
>>> d2=dict()
>>> d3=dict(name='Cherish',age=18)
>>> d1
{'age': 28, 'name': 'Milton'}
>>> d2
{}
>>> d3
{'age': 18, 'name': 'Cherish'}
>>>
dict 字典内置函数有：
>>> dir(d1) ['__class__', '__cmp__', '__contains__', '__delattr__', '__delitem__', '__doc__', '__eq__', '__format__', '__ge__', etattribute__', '__getitem__', '__gt__', '__hash__', '__init__', '__iter__', '__le__', '__len__', '__lt__', '__ne__ _new__', '__reduce__', '__reduce_ex__', '__repr__', '__setattr__', '__setitem__', '__sizeof__', '__str__', '__subcl ok__', 'clear', 'copy', 'fromkeys', 'get', 'has_key', 'items', 'iteritems', 'iterkeys', 'itervalues', 'keys', 'pop' pitem', 'setdefault', 'update', 'values', 'viewitems', 'viewkeys', 'viewvalues'] >>>
dict 字典实例：
D.clear() -> None. Remove all items from D. 清除字典所有内容
>>> d1={'name':'Milton','age':28}
>>> d1
{'age': 28, 'name': 'Milton'}
>>> d1.clear()
>>> d1
{}
D.copy() -> a shallow copy of D. 浅拷贝
>>> d1={'name':'Milton','age':28}
>>> d2=d1.copy()
>>> d2
{'age': 28, 'name': 'Milton'}
D.fromkeys(S[,v]) -> New dict with keys from S and values equal to v. 创建新字典，新字典以S字典的keys作为新字典的keys，values值为v，v默认为None
>>> d1={'name':'Milton','age':28}
>>> dict.fromkeys(d1)
{'age': None, 'name': None}
>>> dict.fromkeys(d1,10)
{'age': 10, 'name': 10}
>>> dict.fromkeys(d1,["v1","v2"])
{'age': ['v1', 'v2'], 'name': ['v1', 'v2']}
>>>
D.get(k[,d]) -> D[k] if k in D, else d. d defaults to None. 根据key获取值，d是默认值
>>> d1={'name':'Milton','age':28}
>>> d1.get("name")
'Milton'
>>> d1.get("sex")
>>> d1.get("sex","F")
'F'
>>>
D.has_key(k) -> True if D has a key k, else False. 判断字典中是否存在key k，如果存在返回True，否则返回False
>>> d1={'name':'Milton','age':28}
>>> d1.has_key("name")
True
>>> d1.has_key("sex")
False
>>>
D.items() -> list of D's (key, value) pairs, as 2-tuples. 返回一个列表，列表中每一个元素是原字典中的key，value组成的元组对
>>> d1={'name':'Milton','age':28}
>>> d1.items()
[('age', 28), ('name', 'Milton')]
>>>
D.keys() -> list of D's keys. 返回一个列表，列表中的元素是原字典中的keys
>>> d1={'name':'Milton','age':28}
>>> d1.keys()
['age', 'name']
>>>
D.values() -> list of D's values. 返回一个列表，列表中的元素是原字典的values
>>> d1={'name':'Milton','age':28}
>>> d1.values()
[28, 'Milton']
>>>
D.pop(k[,d]) -> v, remove specified key and return the corresponding value. 从字典中删除指定key，同时返回该key的值
>>> d1={'name':'Milton','age':28}
>>> d1
{'age': 28, 'name': 'Milton'}
>>> d1.pop("age")
28
>>> d1
{'name': 'Milton'}
八、set集合：set 类源码分析
set是一个无序且不重复的元素集合
class set(object): """ set() -> new empty set object set(iterable) -> new set object Build an unordered collection of unique elements. """ def add(self, *args, **kwargs): # real signature unknown """ 添加 """ """ Add an element to a set. This has no effect if the element is already present. """ pass def clear(self, *args, **kwargs): # real signature unknown """ Remove all elements from this set. """ pass def copy(self, *args, **kwargs): # real signature unknown """ Return a shallow copy of a set. """ pass def difference(self, *args, **kwargs): # real signature unknown """ Return the difference of two or more sets as a new set. (i.e. all elements that are in this set but not the others.) """ pass def difference_update(self, *args, **kwargs): # real signature unknown """ 删除当前set中的所有包含在 new set 里的元素 """ """ Remove all elements of another set from this set. """ pass def discard(self, *args, **kwargs): # real signature unknown """ 移除元素 """ """ Remove an element from a set if it is a member. If the element is not a member, do nothing. """ pass def intersection(self, *args, **kwargs): # real signature unknown """ 取交集，新创建一个set """ """ Return the intersection of two or more sets as a new set. (i.e. elements that are common to all of the sets.) """ pass def intersection_update(self, *args, **kwargs): # real signature unknown """ 取交集，修改原来set """ """ Update a set with the intersection of itself and another. """ pass def isdisjoint(self, *args, **kwargs): # real signature unknown """ 如果没有交集，返回true """ """ Return True if two sets have a null intersection. """ pass def issubset(self, *args, **kwargs): # real signature unknown """ 是否是子集 """ """ Report whether another set contains this set. """ pass def issuperset(self, *args, **kwargs): # real signature unknown """ 是否是父集 """ """ Report whether this set contains another set. """ pass def pop(self, *args, **kwargs): # real signature unknown """ 移除 """ """ Remove and return an arbitrary set element. Raises KeyError if the set is empty. """ pass def remove(self, *args, **kwargs): # real signature unknown """ 移除 """ """ Remove an element from a set; it must be a member. If the element is not a member, raise a KeyError. """ pass def symmetric_difference(self, *args, **kwargs): # real signature unknown """ 差集，创建新对象""" """ Return the symmetric difference of two sets as a new set. (i.e. all elements that are in exactly one of the sets.) """ pass def symmetric_difference_update(self, *args, **kwargs): # real signature unknown """ 差集，改变原来 """ """ Update a set with the symmetric difference of itself and another. """ pass def union(self, *args, **kwargs): # real signature unknown """ 并集 """ """ Return the union of sets as a new set. (i.e. all elements that are in either set.) """ pass def update(self, *args, **kwargs): # real signature unknown """ 更新 """ """ Update a set with the union of itself and others. """ pass def __and__(self, y): # real signature unknown; restored from __doc__ """ x.__and__(y) <==> x&y """ pass def __cmp__(self, y): # real signature unknown; restored from __doc__ """ x.__cmp__(y) <==> cmp(x,y) """ pass def __contains__(self, y): # real signature unknown; restored from __doc__ """ x.__contains__(y) <==> y in x. """ pass def __eq__(self, y): # real signature unknown; restored from __doc__ """ x.__eq__(y) <==> x==y """ pass def __getattribute__(self, name): # real signature unknown; restored from __doc__ """ x.__getattribute__('name') <==> x.name """ pass def __ge__(self, y): # real signature unknown; restored from __doc__ """ x.__ge__(y) <==> x>=y """ pass def __gt__(self, y): # real signature unknown; restored from __doc__ """ x.__gt__(y) <==> x>y """ pass def __iand__(self, y): # real signature unknown; restored from __doc__ """ x.__iand__(y) <==> x&=y """ pass def __init__(self, seq=()): # known special case of set.__init__ """ set() -> new empty set object set(iterable) -> new set object Build an unordered collection of unique elements. # (copied from class doc) """ pass def __ior__(self, y): # real signature unknown; restored from __doc__ """ x.__ior__(y) <==> x|=y """ pass def __isub__(self, y): # real signature unknown; restored from __doc__ """ x.__isub__(y) <==> x-=y """ pass def __iter__(self): # real signature unknown; restored from __doc__ """ x.__iter__() <==> iter(x) """ pass def __ixor__(self, y): # real signature unknown; restored from __doc__ """ x.__ixor__(y) <==> x^=y """ pass def __len__(self): # real signature unknown; restored from __doc__ """ x.__len__() <==> len(x) """ pass def __le__(self, y): # real signature unknown; restored from __doc__ """ x.__le__(y) <==> x<=y """ pass def __lt__(self, y): # real signature unknown; restored from __doc__ """ x.__lt__(y) <==> x<y """ pass @staticmethod # known case of __new__ def __new__(S, *more): # real signature unknown; restored from __doc__ """ T.__new__(S, ...) -> a new object with type S, a subtype of T """ pass def __ne__(self, y): # real signature unknown; restored from __doc__ """ x.__ne__(y) <==> x!=y """ pass def __or__(self, y): # real signature unknown; restored from __doc__ """ x.__or__(y) <==> x|y """ pass def __rand__(self, y): # real signature unknown; restored from __doc__ """ x.__rand__(y) <==> y&x """ pass def __reduce__(self, *args, **kwargs): # real signature unknown """ Return state information for pickling. """ pass def __repr__(self): # real signature unknown; restored from __doc__ """ x.__repr__() <==> repr(x) """ pass def __ror__(self, y): # real signature unknown; restored from __doc__ """ x.__ror__(y) <==> y|x """ pass def __rsub__(self, y): # real signature unknown; restored from __doc__ """ x.__rsub__(y) <==> y-x """ pass def __rxor__(self, y): # real signature unknown; restored from __doc__ """ x.__rxor__(y) <==> y^x """ pass def __sizeof__(self): # real signature unknown; restored from __doc__ """ S.__sizeof__() -> size of S in memory, in bytes """ pass def __sub__(self, y): # real signature unknown; restored from __doc__ """ x.__sub__(y) <==> x-y """ pass def __xor__(self, y): # real signature unknown; restored from __doc__ """ x.__xor__(y) <==> x^y """ pass __hash__ = None set
python2中，set集合如：set(['a','b','c','d',1,2,3])
>>> s1=set()
>>> s1
set([])
>>> s2=set(["a","b","c","d",1,2,3])
>>> s2
set(['a', 1, 'c', 'b', 'd', 2, 3])
>>> s3=set("abcd123")
>>> s3
set(['a', 'c', 'b', 'd', '1', '3', '2'])
python3中，set集合如：{'a','b','c','d',1,2,3}
>>> s1=set()
>>> s1
set()
>>> s2=set(['a','b','c','d',1,2,3])
>>> s2
{1, 'd', 2, 'a', 3, 'c', 'b'}
>>> s3={'a','b','c','d',1,2,3}
>>> s3
{1, 2, 3, 'd', 'a', 'c', 'b'}
>>> type(s3)
<class 'set'>
set 实例：
add() -> Add an element to a set. 添加元素
>>> s1=set()
>>> s1
set([])
>>> s1.add("a")
>>> s1
set(['a'])
clear() -> Remove all elements from this set.清空set集合
>>> s1 set(['a', 'c', 'b', 'd']) >>> s1.clear() >>> s1 set([])
difference() ->Return the difference of two or more sets as a new set. 如 s1.difference(s2)， 返回一个新的集合，新集合中的元素在s1中，不在s2中。
difference_update() -> Remove all elements of another set from this set. 如s1.difference(s2),直接在s1集合中，删除同时存在s2中的那部分元素。
>>> s1=set(["a","b","c","d"]) >>> s1 set(['a', 'c', 'b', 'd']) >>> s2=set(["c","d",1,2]) >>> s2 set([1, 'c', 2, 'd']) >>> s1.difference(s2) set(['a', 'b'])
>>> s1
set(['a','c','b','d'])
>>> s1.difference_update(s2)
>>> s1
set(['a','b'])
discard() -> Remove an element from a set if it is a member. 删除set集合中的元素
>>> s1
set(['a', 'b'])
>>> s1.discard('a')
>>> s1
set(['b'])
intersection() -> Return the intersection of two or more sets as a new set. 如 s1.intersection(s2), 取交集，新创建一个set
intersection_update() -> Update a set with the intersection of itself and another.如 s1.intersection(s2), 取交集,修改原来set
>>> s1=set(["a","b","c","d"]) >>> s2=set(["c","d",1,2]) >>> s1.intersection(s2) set(['c', 'd']) >>> s1 set(['a', 'c', 'b', 'd']) >>> s1.intersection_update(s2) >>> s1 set(['c', 'd'])
symmetric_difference() -> Return the symmetric difference of two sets as a new set. 差集，创建新对象
symmetric_difference_update()-> Update a set with the symmetric difference of itself and another.差集，修改原集合
>>> s1=set(["a","b","c","d"]) >>> s2=set(["c","d",1,2]) >>> s1.symmetric_difference(s2) set(['a', 1, 2, 'b']) >>> s1 set(['a', 'c', 'b', 'd']) >>> s1.symmetric_difference_update(s2) >>> s1 set(['a', 1, 2, 'b'])
union() -> Return the union of sets as a new set. 返回两个集合的并集
>>> s1=set(["a","b","c","d"]) >>> s2=set(["c","d",1,2]) >>> s1.union(s2) set(['a', 1, 'c', 'b', 'd', 2])
update() -> Update a set with the union of itself and others. 更新集合，如s1.update(s2),将s2中的内容更新到s1中
>>> s1=set(["a","b","c","d"]) >>> s2=set(["c","d",1,2]) >>> s1.update(s2) >>> s1 set(['a', 1, 'c', 'b', 'd', 2])
