Python基础篇【第五篇】：sed和函数

sed是一个无序且不重复的元素集合

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

以上常用实例：

 1 #!/usr/bin/env python3
 2 
 3 # se = {11,22,33}
 4 # be = {55}
 5 
 6 # #增加
 7 # se.add(44)
 8 # print(se)
 9 
10 # 更新
11 # se.update(be)
12 # print(se)
13 
14 # #清除
15 # se.clear()
16 # print(se)
17 
18 # #找se中存在的be不存在的
19 # se.difference(be)
20 # ret = se.difference(be)
21 # print(se)
22 # print(ret)
23 
24 
25 # #找se中存在,be中不存在的集合,更新自己
26 # se.difference_update(be)
27 # print(se)
28 
29 # #移除指定的元素,不存在不报错
30 # se.discard(11)
31 # print(se)
32 
33 # #移除元素,不存在会报错
34 # se.remove(11)
35 # print(se)
36 
37 # #取交集
38 # ret = se.intersection(be)
39 # print(ret)
40 
41 # #取交集并更新
42 # se.intersection_update(be)
43 # print(se)
44 
45 # #判断交集有false,没有true
46 # ret = se.isdisjoint(be)
47 # print(ret)
48 
49 #子序列,父序列,谁多谁是父亲,谁少谁是儿子
50 # ret = se.issubset(be)
51 # print(ret)
52 # ret = se.issuperset(be)
53 # print(ret)
54 
55 #移除
56 # ret = se.pop()
57 # print(ret)
58 
59 #对称交集
60 # set = se.symmetric_difference(be)
61 # print(set)
62 
63 # #对称交集更新
64 # se.symmetric_difference_update(be)
65 # print(se)
66 
67 #并集
68 # ret = se.union(be)
69 # print(ret)
70 
71 # se = {11,22,33}
72 # be = {22,55}
73 # for i in se:
74 #     print(se)
75 #
76 # ret = 11 in se
77 # print(ret)

深、浅copy

1、深拷贝是在另一块地址中创建一个新的变量或容器，同时容器内的元素的地址也是新开辟的，仅仅是值相同而已，是完全的副本。

2、浅拷贝是在另一块地址中创建一个新的变量或容器，但是容器内的元素的地址均是源对象的元素的地址的拷贝。也就是说新的容器中指向了旧的元素。

函数

函数是组织好的，可重复使用的，用来实现单一，或相关联功能的代码段。

函数能提高应用的模块性，和代码的重复利用率。你已经知道Python提供了许多内建函数，比如print()。但你也可以自己创建函数，这被叫做用户自定义函数。

定义函数：　

  • 函数代码块以 def 关键词开头，后接函数标识符名称和圆括号 ()。
  • 任何传入参数和自变量必须放在圆括号中间，圆括号之间可以用于定义参数。
  • 函数的第一行语句可以选择性地使用文档字符串—用于存放函数说明。
  • 函数内容以冒号起始，并且缩进。
  • return [表达式] 结束函数，选择性地返回一个值给调用方。不带表达式的return相当于返回 None。

语法：

1 def 函数名字（形参）：
2     函数体

默认情况下，参数值和参数名称是按函数声明中定义的的顺序匹配起来的。

实例：

1 def hello():
2     print('hello~')

调用函数：

1 #!/usr/bin/env python3
2 
3 def test(str):
4     print(str)
5     return6 
7 print("调用")
posted @ 2016-05-08 22:08  汪汪小喵咪  阅读(649)  评论(0)  编辑  收藏  举报