Python数据类型的操作——列表、元组

一、列表的索引和切片

 1 li = ['a','b','c',1,2,3]
 2 print(li[0])
 3 print(li[2])
 4 print(li[-1])
 5 # a
 6 # c
 7 # 3
 8 #切片
 9 print(li[0:3])
10 print(li[2:5])
11 print(li[0:5:2])
12 # ['a', 'b', 'c']
13 # ['c', 1, 2]
14 # ['a', 'c', 2]

二、增

2.1、append(self, p_object) 添加

1 Demo = ['name','age','job']
2 Demo.append('hobby')     #在列表后面新增元素 
3 print(Demo)
4 Demo.append([1,'hehe',True])
5 print(Demo)                            #直接添加整个列表
6 # ['name', 'age', 'job', 'hobby']
7 # ['name', 'age', 'job', 'hobby', [1, 'hehe', True]]

2.2、insert(self, index, p_object) 插入

1 Demo = ['name','age','job']
2 Demo.insert(1,'kitty')    #通过索引插入
3 print(Demo)
4 # ['name', 'kitty', 'age', 'job']

nsert()只能通过索引插入

2.3、extend(self, iterable)

在列表后面可迭代的添加

 1 Demo = ['name','age','job']
 2 Demo.extend(' ')
 3 print(Demo)
 4 # ['name', 'age', 'job', ' ']
 5 Demo = ['name','age','job']
 6 Demo.extend('a')
 7 print(Demo)
 8 # ['name', 'age', 'job', 'a']
 9 Demo = ['name','age','job']
10 Demo.extend('abc')          #可迭代的对象拆分遍历后添加
11 print(Demo)
12 # ['name', 'age', 'job', 'a', 'b', 'c']
13 Demo = ['name','age','job']
14 Demo.extend(['abc','b','c'])   #可迭代的对象拆分(子序列)遍历后添加
15 print(Demo)
16 # ['name', 'age', 'job', 'abc', 'b', 'c']

extend()

三、删

3.1、pop(self, index=None)

通过索引删除

1 Demo = ['name','age','job']
2 t = Demo.pop(1)    #pop(索引)
3 print(Demo)
4 print(t)
5 # ['name', 'job']
6 # age

3.2、remove(self, value)

直接删除看到的值

1 Demo = ['name','age','job']
2 Demo.remove('age')
3 print(Demo)
4 # ['name', 'job']

3.3、clear(self)

清空列表

1 Demo = ['name','age','job']
2 Demo.clear()
3 print(Demo)
4 # []

3.4、del

删除

 1 Demo = ['name','age','job','wall_e','eva',1,2,3]
 2 del Demo[2]     #索引删除
 3 print(Demo)
 4 # ['name', 'age', 'wall_e', 'eva', 1, 2, 3]
 5 Demo = ['name','age','job','wall_e','eva',1,2,3]
 6 del Demo[2:6:2]   #切片删除
 7 print(Demo)
 8 # ['name', 'age', 'wall_e', 1, 2, 3]
 9 Demo = ['name','age','job','wall_e','eva',1,2,3]
10 del Demo               #把列表删了，列表不存在了，报错   not defined
11 print(Demo)
12 # Traceback (most recent call last):
13 #   File "D:/Demo/test.py", line 11, in <module>
14 #     print(Demo)
15 # NameError: name 'Demo' is not defined

del

四、改

4.1 通过索引改

4.2 通过切片改（添加可迭代的对象）

1 Demo = ['name','age','job','wall_e','eva',1,2,3]
2 Demo[2] = 'hobby'
3 print(Demo)
4 # ['name', 'age', 'hobby', 'wall_e', 'eva', 1, 2, 3]
5 Demo = ['name','age','job','wall_e','eva',1,2,3]
6 Demo[2:5:] = 'abcde'
7 print(Demo)
8 # ['name', 'age', 'a', 'b', 'c', 'd', 'e', 1, 2, 3]

五、查

通过索引查

通过切片查

通过for循环列出查看

 1 Demo = ['name','age','job','wall_e','eva',1,2,3]
 2 print(Demo[2])
 3 # job
 4 print(Demo[5:0:-2])
 5 # [1, 'wall_e', 'age']
 6 
 7 li = ['aefc','df',1,5,3]
 8 for i in li:
 9     print(i)
10 # aefc
11 # df
12 # 1
13 # 5
14 # 3

###枚举 enumerrate(self, iterable, start = 0)

iterable: str, list, tuple, dict, set

 1 li = ['a','b','c','d']
 2 for i in enumerate(li):
 3     print(i)
 4 # (0, 'a')
 5 # (1, 'b')
 6 # (2, 'c')
 7 # (3, 'd')
 8 for i in enumerate(li,6)
 9 (# (6, 'a')
10 # (7, 'b')
11 # (8, 'c')
12 # (9, 'd')

六、index()

通过值取索引

七、count 计数

1 Demo = ['name','age',['name','wall_e','name',1],2,'name']
2 print(Demo.count('name'))
3 # 2
4 print(Demo.count('haha'))
5 # 0

八、排序

sort(self, key=None, reverse=False) 正序
sort(reverse=True) 倒序

1 Demo = [1,2,3,7,6,0,4,5]
2 Demo.sort()
3 print(Demo)
4 Demo = [1,2,3,7,6,0,4,5]
5 Demo.sort(reverse=True)
6 print(Demo)
7 # [0, 1, 2, 3, 4, 5, 6, 7]
8 # [7, 6, 5, 4, 3, 2, 1, 0]

九、reverse(self) 反转

1 Demo = [1,2,3,7,6,0,4,5]
2 Demo.reverse()
3 print(Demo)
4 # [5, 4, 0, 6, 7, 3, 2, 1]

### 将字符串转换成列表，split
将列表转换成字符串，join （列表的每个值都是字符串）

1 b = ['a','b','c']
2 a = '_'.join(b)
3 print(a)
4 # a_b_c
5 
6 a = 'Tom'
7 b = '5'.join(a)
8 print(b)
9 # T5o5m

十、列表的嵌套

 1 Demo = ['name','age',['job','wall_e','eva',1],2,3]
 2 Demo[1] = 'AGE'
 3 print(Demo)
 4 # ['name', 'AGE', ['job', 'wall_e', 'eva', 1], 2, 3]
 5 Demo = ['name','age',['job','wall_e','eva',1],2,3]
 6 Demo[1] = Demo[1].upper()
 7 print(Demo)
 8 # ['name', 'AGE', ['job', 'wall_e', 'eva', 1], 2, 3]
 9 #***必须把新生成的AGE 替换掉原来的，  （通过索引改）
10 Demo = ['name','age',['job','wall_e','eva',1],2,3]
11 Demo[2][2] = Demo[2][2].upper()
12 print(Demo)
13 # ['name', 'age', ['job', 'wall_e', 'EVA', 1], 2, 3]
14 
15 #列表元素  首字母大写
16 Demo = ['name','age',['job','wall_e','eva',1],2,3]
17 Demo[0].capitalize()
18 print(Demo)
19 print(Demo[0].capitalize())
20 # ['name', 'age', ['job', 'wall_e', 'eva', 1], 2, 3]
21 # Name
22 #不替换新的元素，原列表是不变的，即使列表是可变类型，因为字符串是不可变类型，
23 #对字符串的操作不会改变原字符串
24 Demo[0] = Demo[0].capitalize()
25 print(Demo)
26 # ['Name', 'age', ['job', 'wall_e', 'eva', 1], 2, 3]

list[list]

十一、元组

只读，不可修改
元组不可修改，但是元组如果包含列表，列表的内容可以更改

 1 a = (1,3,5)
 2 a[1] = 9       #报错，tuple 对象不支持更改
 3 print(a)    
 4 # Traceback (most recent call last):
 5 #   File "D:/Demo/test.py", line 2, in <module>
 6 #     a[1] = 9
 7 # TypeError: 'tuple' object does not support item assignment
 8 
 9 Demo = ('name','age',['wall_e','name',1],2)
10 Demo[2][1] = 'job'
11 print(Demo)
12 # ('name', 'age', ['wall_e', 'job', 1], 2)

十二、range()

包含指定范围

1 for i in range (1,10,2):  #可加步长
2     print(i)

posted @ 2017-10-24 23:42 静静别跑阅读(166) 评论(0) 编辑收藏举报

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