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  • python基础1

    注:部分内容摘自:http://www.cnblogs.com/wupeiqi/articles/4911365.html。

    一、整数
    如:12, 45, 23
    1.def bit_length(self):
        """ 返回表示该数字的时占用的最少位数 """
        >>>(12).bit-length()
        4
        >>>bin(12)
        '0b1100'

    2.def __abs__(self):
            """ 返回绝对值 """
            """ x.__abs__() <==> abs(x) """
            pass
    3.def __add__(self, y):
            """ x.__add__(y) <==> x+y """
            pass
    4.def __and__(self, y):
            """ x.__and__(y) <==> x&y """
            pass   #在二进制位取与运算
    5.def __coerce__(self, y):
            """ 强制生成一个元组 """
            """ x.__coerce__(y) <==> coerce(x, y) """
            pass
    6.def __divmod__(self, y):
            """ 相除,得到商和余数组成的元组 """
            """ x.__divmod__(y) <==> divmod(x, y) """
            pass
    7.def __div__(self, y):
            """ x.__div__(y) <==> x/y """
            pass
    8.def __float__(self):
            """ 转换为浮点类型 """
            """ x.__float__() <==> float(x) """
            pass
    9. def __int__(self):
            """ 转换为整数 """
            """ x.__int__() <==> int(x) """
            pass
    10. def __long__(self):
            """ 转换为长整数 """
            """ x.__long__() <==> long(x) """
            pass
    二:长整型
    1.def bit_length(self): # real signature unknown; restored from __doc__
            """
            long.bit_length() -> int or long
            
            Number of bits necessary to represent self in binary.
            >>> bin(37L)
            '0b100101'
            >>> (37L).bit_length()
            6
    三:浮点型
    四:字符串
    s = 'spam'
    1.find   #查到的话,返回字符的偏移量,没有查到的话,返回-1
      >>>s.find(p)
      1  
    2.replace
      >>>s.replace('pa','XXX')
      'sXXXm'
    3.分割
      >>>line = 'aa,bb,cc,dd'
         lin.split(,)  #括号内指定分隔符,为空则为空格。
      ['aa','bb','cc','dd']    
    4. 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')
            """
    5.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 ""
    6.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
    7.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
    8.def isalpha(self):  
            """ 是否是字母 """
    9.def isdigit(self):  
            """ 是否是数字 """
    10.def islower(self):  
            """ 是否小写 """
    11. def lstrip(self, chars=None):  
            """ 移除左侧空白 """
            """
    12.def swapcase(self):  
            """ 大写变小写,小写变大写 """
            """
        
    需求帮助:
    >>>dir(line)
    >>>help
    五:列表
    1. 追加
    def append(self, p_object):
            """ L.append(object) -- append object to end """
            pass
    2.计数
     def count(self, value):
            """ L.count(value) -> integer -- return number of occurrences of value """
            return 0
    3.扩展
    def extend(self, iterable):
            """ L.extend(iterable) -- extend list by appending elements from the iterable """
            pass
    4.删除 pop()中间没有值的话删除最后一个并返回值
    def pop(self, index=None):
            """
            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
    5.删除指定元素
    def remove(self, value):
            """
            L.remove(value) -- remove first occurrence of value.
            Raises ValueError if the value is not present.
            """
            pass        
    6.反转
    def reverse(self):
            """ L.reverse() -- reverse *IN PLACE* """
            pass
    7.排序
    def sort(self, cmp=None, key=None, reverse=False):
            """
            L.sort(cmp=None, key=None, reverse=False) -- stable sort *IN PLACE*;
            cmp(x, y) -> -1, 0, 1
            """
            pass
    8.插入
     def insert(self, index, p_object):
            """ L.insert(index, object) -- insert object before index """
            pass        
    9.def __add__(self, y):
            """ x.__add__(y) <==> x+y """
            pass
    10.包含
    def __contains__(self, y):
            """ x.__contains__(y) <==> y in x """
            pass
    11.判断长度
    def __len__(self):
            """ x.__len__() <==> len(x) """
            pass
    六:字典
    1.def clear(self):
            """ 清除内容 """
            """ D.clear() -> None.  Remove all items from D. """
            pass
    2.def copy(self):
            """ 浅拷贝 """
            """ D.copy() -> a shallow copy of D """
            pass
    3.def get(self, k, d=None):
            """ 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        
    4.def has_key(self, k):
            """ 是否有key """
            """ D.has_key(k) -> True if D has a key k, else False """
            return False        
    5.def keys(self):
            """ 所有的key列表 """
            """ D.keys() -> list of D's keys """
            return []        
    6.def pop(self, k, d=None):
            """ 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
            """
    7.def popitem(self):
            """ 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.
            """
    8.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
    9.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        
           

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  • 原文地址:https://www.cnblogs.com/ernest-zhang/p/5312126.html
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