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  • 运算符与基本数据类型(int,boolean,str)

    一· 运算符

      in与not in

          判断某个字符串是否是另一个字符串的子序列

          如果使用in,当这个字符串是另一个字符串的子序列时,返回True;如果不是,返回False.

          如果使用 not in, 返回结果和in相反。

    二· 基本数据类型

    1. 数字

    int(整形):在python3.5中,所有的数字都属于int型,而在python2中,当数字超过了某个范围,还有long长整形。

    常用方法:

    #将字符串转换为数字
    a = "123"
    b = int(a) print(type(b),b)
    num = "0011" v = int(num, base=16)
    #将字符串转换为16进制后代表的十进制数
    print(v)
    #bit_lenght 当前数字的二进制,至少用n位表示,返回这个n r = age.bit_length()
    class int(object):
        """
        int(x=0) -> int or long
        int(x, base=10) -> int or long
        
        Convert a number or string to an integer, or return 0 if no arguments
        are given.  If x is floating point, the conversion truncates towards zero.
        If x is outside the integer range, the function returns a long instead.
        
        If x is not a number or if base is given, then x must be a string or
        Unicode object representing an integer literal in the given base.  The
        literal can be preceded by '+' or '-' and be surrounded by whitespace.
        The base defaults to 10.  Valid bases are 0 and 2-36.  Base 0 means to
        interpret the base from the string as an integer literal.
        >>> int('0b100', base=0)
        4
        """
        def bit_length(self): 
            """ 返回表示该数字的时占用的最少位数 """
            """
            int.bit_length() -> int
            
            Number of bits necessary to represent self in binary.
            >>> bin(37)
            '0b100101'
            >>> (37).bit_length()
            6
            """
            return 0
    
        def conjugate(self, *args, **kwargs): # real signature unknown
            """ 返回该复数的共轭复数 """
            """ Returns self, the complex conjugate of any int. """
            pass
    
        def __abs__(self):
            """ 返回绝对值 """
            """ x.__abs__() <==> abs(x) """
            pass
    
        def __add__(self, y):
            """ x.__add__(y) <==> x+y """
            pass
    
        def __and__(self, y):
            """ x.__and__(y) <==> x&y """
            pass
    
        def __cmp__(self, y): 
            """ 比较两个数大小 """
            """ x.__cmp__(y) <==> cmp(x,y) """
            pass
    
        def __coerce__(self, y):
            """ 强制生成一个元组 """ 
            """ x.__coerce__(y) <==> coerce(x, y) """
            pass
    
        def __divmod__(self, y): 
            """ 相除,得到商和余数组成的元组 """ 
            """ x.__divmod__(y) <==> divmod(x, y) """
            pass
    
        def __div__(self, y): 
            """ x.__div__(y) <==> x/y """
            pass
    
        def __float__(self): 
            """ 转换为浮点类型 """ 
            """ x.__float__() <==> float(x) """
            pass
    
        def __floordiv__(self, y): 
            """ x.__floordiv__(y) <==> x//y """
            pass
    
        def __format__(self, *args, **kwargs): # real signature unknown
            pass
    
        def __getattribute__(self, name): 
            """ x.__getattribute__('name') <==> x.name """
            pass
    
        def __getnewargs__(self, *args, **kwargs): # real signature unknown
            """ 内部调用 __new__方法或创建对象时传入参数使用 """ 
            pass
    
        def __hash__(self): 
            """如果对象object为哈希表类型,返回对象object的哈希值。哈希值为整数。在字典查找中,哈希值用于快速比较字典的键。两个数值如果相等,则哈希值也相等。"""
            """ x.__hash__() <==> hash(x) """
            pass
    
        def __hex__(self): 
            """ 返回当前数的 十六进制 表示 """ 
            """ x.__hex__() <==> hex(x) """
            pass
    
        def __index__(self): 
            """ 用于切片,数字无意义 """
            """ x[y:z] <==> x[y.__index__():z.__index__()] """
            pass
    
        def __init__(self, x, base=10): # known special case of int.__init__
            """ 构造方法,执行 x = 123 或 x = int(10) 时,自动调用,暂时忽略 """ 
            """
            int(x=0) -> int or long
            int(x, base=10) -> int or long
            
            Convert a number or string to an integer, or return 0 if no arguments
            are given.  If x is floating point, the conversion truncates towards zero.
            If x is outside the integer range, the function returns a long instead.
            
            If x is not a number or if base is given, then x must be a string or
            Unicode object representing an integer literal in the given base.  The
            literal can be preceded by '+' or '-' and be surrounded by whitespace.
            The base defaults to 10.  Valid bases are 0 and 2-36.  Base 0 means to
            interpret the base from the string as an integer literal.
            >>> int('0b100', base=0)
            4
            # (copied from class doc)
            """
            pass
    
        def __int__(self): 
            """ 转换为整数 """ 
            """ x.__int__() <==> int(x) """
            pass
    
        def __invert__(self): 
            """ x.__invert__() <==> ~x """
            pass
    
        def __long__(self): 
            """ 转换为长整数 """ 
            """ x.__long__() <==> long(x) """
            pass
    
        def __lshift__(self, y): 
            """ x.__lshift__(y) <==> x<<y """
            pass
    
        def __mod__(self, y): 
            """ x.__mod__(y) <==> x%y """
            pass
    
        def __mul__(self, y): 
            """ x.__mul__(y) <==> x*y """
            pass
    
        def __neg__(self): 
            """ x.__neg__() <==> -x """
            pass
    
        @staticmethod # known case of __new__
        def __new__(S, *more): 
            """ T.__new__(S, ...) -> a new object with type S, a subtype of T """
            pass
    
        def __nonzero__(self): 
            """ x.__nonzero__() <==> x != 0 """
            pass
    
        def __oct__(self): 
            """ 返回改值的 八进制 表示 """ 
            """ x.__oct__() <==> oct(x) """
            pass
    
        def __or__(self, y): 
            """ x.__or__(y) <==> x|y """
            pass
    
        def __pos__(self): 
            """ x.__pos__() <==> +x """
            pass
    
        def __pow__(self, y, z=None): 
            """ 幂,次方 """ 
            """ x.__pow__(y[, z]) <==> pow(x, y[, z]) """
            pass
    
        def __radd__(self, y): 
            """ x.__radd__(y) <==> y+x """
            pass
    
        def __rand__(self, y): 
            """ x.__rand__(y) <==> y&x """
            pass
    
        def __rdivmod__(self, y): 
            """ x.__rdivmod__(y) <==> divmod(y, x) """
            pass
    
        def __rdiv__(self, y): 
            """ x.__rdiv__(y) <==> y/x """
            pass
    
        def __repr__(self): 
            """转化为解释器可读取的形式 """
            """ x.__repr__() <==> repr(x) """
            pass
    
        def __str__(self): 
            """转换为人阅读的形式,如果没有适于人阅读的解释形式的话,则返回解释器课阅读的形式"""
            """ x.__str__() <==> str(x) """
            pass
    
        def __rfloordiv__(self, y): 
            """ x.__rfloordiv__(y) <==> y//x """
            pass
    
        def __rlshift__(self, y): 
            """ x.__rlshift__(y) <==> y<<x """
            pass
    
        def __rmod__(self, y): 
            """ x.__rmod__(y) <==> y%x """
            pass
    
        def __rmul__(self, y): 
            """ x.__rmul__(y) <==> y*x """
            pass
    
        def __ror__(self, y): 
            """ x.__ror__(y) <==> y|x """
            pass
    
        def __rpow__(self, x, z=None): 
            """ y.__rpow__(x[, z]) <==> pow(x, y[, z]) """
            pass
    
        def __rrshift__(self, y): 
            """ x.__rrshift__(y) <==> y>>x """
            pass
    
        def __rshift__(self, y): 
            """ x.__rshift__(y) <==> x>>y """
            pass
    
        def __rsub__(self, y): 
            """ x.__rsub__(y) <==> y-x """
            pass
    
        def __rtruediv__(self, y): 
            """ x.__rtruediv__(y) <==> y/x """
            pass
    
        def __rxor__(self, y): 
            """ x.__rxor__(y) <==> y^x """
            pass
    
        def __sub__(self, y): 
            """ x.__sub__(y) <==> x-y """
            pass
    
        def __truediv__(self, y): 
            """ x.__truediv__(y) <==> x/y """
            pass
    
        def __trunc__(self, *args, **kwargs): 
            """ 返回数值被截取为整形的值,在整形中无意义 """
            pass
    
        def __xor__(self, y): 
            """ x.__xor__(y) <==> x^y """
            pass
    
        denominator = property(lambda self: object(), lambda self, v: None, lambda self: None)  # default
        """ 分母 = 1 """
        """the denominator of a rational number in lowest terms"""
    
        imag = property(lambda self: object(), lambda self, v: None, lambda self: None)  # default
        """ 虚数,无意义 """
        """the imaginary part of a complex number"""
    
        numerator = property(lambda self: object(), lambda self, v: None, lambda self: None)  # default
        """ 分子 = 数字大小 """
        """the numerator of a rational number in lowest terms"""
    
        real = property(lambda self: object(), lambda self, v: None, lambda self: None)  # default
        """ 实属,无意义 """
        """the real part of a complex number"""
    int源代码

    2. 字符串

    str(字符串):所有用‘ ‘ 或者“ ”包裹的数据。

    常用方法:

    # join       # '_'.join("asdfasdf")  字符串拼接效率最高的方法
    # split      字符串切割
    # find       寻找某一个子序列,返回子序列第一个字符的下标值
    # strip      清除左右的空格或者	,
    
    # upper 字符全部变成大写 # lower 字符全部变成小写 # replace 替换字符串中的某个子序列
    # len 获取字符串的字符个数
    # 字符串名[1:-1:1] 切片
    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
    string源代码

     3. boolean

    boolean(布尔值)这种数据类型,只有两个值True和False,常用于逻辑判断。

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  • 原文地址:https://www.cnblogs.com/ithome0222/p/8612195.html
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