列表：是一个加强版的数组，什么东西都可以往里面放。
创建列表
创建一个普通列表：
1 >>> member = ['operating system', 'data structure', 'network', 'principle of computer composition'] 2 >>> member 3 ['operating system', 'data structure', 'network', 'principle of computer composition']
创建一个混合列表：
1 >>> mix = [1, 'hello python', 3.14159, [1,2,3,['one','two']]] 2 >>> mix 3 [1, 'hello python', 3.14159, [1, 2, 3, ['one', 'two']]]
创建一个空列表：
1 >>> empty = [] 2 >>> empty 3 []
向列表中添加元素
使用append()，extend(),和insert()方法
append()在尾部添加，extend()用一个列表来扩展列表，insert(index, obj)在index处插值。
1 >>> member.append('mechine learning') 2 >>> member 3 ['operating system', 'data structure', 'network', 'principle of computer composition', 'mechine learning'] 4 >>> member.extend(['data mining', 'hadoop']) 5 >>> member 6 ['operating system', 'data structure', 'network', 'principle of computer composition', 'mechine learning', 'data mining', 'hadoop'] 7 >>> member.insert(0,'PE') 8 >>> member 9 ['PE', 'operating system', 'data structure', 'network', 'principle of computer composition', 'mechine learning', 'data mining', 'hadoop']
从列表中获取元素
和数组一样，通过元素的索引从列表中获得单个元素，索引从0开始。
1 >>> for i in range(len(member)): 2 ... print(member[i]) 3 ... 4 PE 5 operating system 6 data structure 7 network 8 principle of computer composition 9 mechine learning 10 data mining 11 hadoop
通过列表分片
1 >>> member[3] 2 'network' 3 >>> member[:3] 4 ['PE', 'operating system', 'data structure'] 5 >>> member[3:] 6 ['network', 'principle of computer composition', 'mechine learning', 'data mining', 'hadoop'] 7 >>> member[3:5] 8 ['network', 'principle of computer composition']
从列表中删除元素
使用remove(),pop()方法或del
1 >>> member 2 ['PE', 'operating system', 'data structure', 'network', 'principle of computer composition', 'mechine learning', 'data mining', 'hadoop'] 3 >>> member.remove('hadoop') 4 >>> member 5 ['PE', 'operating system', 'data structure', 'network', 'principle of computer composition', 'mechine learning', 'data mining'] 6 >>> member.pop() 7 'data mining' 8 >>> member 9 ['PE', 'operating system', 'data structure', 'network', 'principle of computer composition', 'mechine learning'] 10 >>> member.pop(2) 11 'data structure' 12 >>> member 13 ['PE', 'operating system', 'network', 'principle of computer composition', 'mechine learning'] 14 >>> del member[3] 15 >>> member 16 ['PE', 'operating system', 'network', 'mechine learning'] 17 >>> del member 18 >>> member 19 Traceback (most recent call last): 20 File "<stdin>", line 1, in <module> 21 NameError: name 'member' is not defined
列表的一些常用操作符
比较操作符 >， >=， < ，<=， == ，!=
1 >>> list1 = [123] 2 >>> list2 = [456] 3 >>> list1 < list2 4 True 5 >>> list1 = [123,456] 6 >>> list2 = [234,123] 7 >>> list1 > list2 8 False
逻辑操作符 and， or， not
1 >>> list3 = [123,456] 2 >>> list1 < list2 and list1 == list3 3 True 4 >>> list1 > list2 or list1 < list2 5 True 6 >>> not list1 < list2 7 False
拼接操作符 *
1 >>> list4 = list2 + list3 2 >>> list4 3 [234, 123, 123, 456]
重复操作符 *
1 >>> list4 2 [234, 123, 123, 456] 3 >>> list4 * 5 4 [234, 123, 123, 456, 234, 123, 123, 456, 234, 123, 123, 456, 234, 123, 123, 456, 234, 123, 123, 456]
成员关系操作符in， not in
1 >>> 123 in list4 2 True 3 >>> 345 in list4 4 False 5 >>> 345 not in list4 6 True
列表一些常用的方法
count():返回列表内某个成员出现次数，如果不存在则返回0
1 >>> list4 2 [234, 123, 123, 456] 3 >>> list4.count(123) 4 2
index()：返回该元素在列表第一次出现位置的索引，若不存在，则抛出一个ValueError异常。
1 >>> list4.index(123) 2 1 3 >>> list4.index(124) 4 Traceback (most recent call last): 5 File "<stdin>", line 1, in <module> 6 ValueError: 124 is not in list
reverse():翻转列表
1 >>> list4 2 [456, 123, 123, 234] 3 >>> list4.reverse() 4 >>> list4 5 [234, 123, 123, 456]