数据类型

基本的数据类型——数字

       布尔型：

                      1. bool型只有两个值：True和False

                      2. 之所以将布尔值归为数字，因为我们习惯用1 表示True，0表示False。

      整型

      浮点型

      复数

基本的数据类型——字符串

                     字符串是一个有序的字符的集合，用于存储和表示基本的文本信息，' '或'' ''或''' '''中间包含的内容称之为字符串

                     字符串的单引号和双引号都无法取消特殊字符的含义，如果想让引号内所有字符均取消特殊意义，在引号前面加r，如name＝r'l hf'

基本的数据类型——列表

                     定义：[]内以逗号分隔，按照索引，存放各种数据类型，每个位置代表一个元素

                     

常用操作：

1. 索引

color = ["red","blue","green","white"]
索引：
print('color[0]')

2. 切片

color = ["red","blue","green","white"]
print("color[0:2]")
>>>red，blue

print("color[1:3]")
>>>blue，green

倒着切

color = ["red","blue","green","white"]
color[-1:-5:-1]

字符串也可以反转
n = "进击的小吴"
n[::-1]
>>>n = "吴小的击进"

3. 追加

color = ["red","blue","green","white"]
color.append("black")
>>>color = ["red","blue","green","white","black"]

插入

color = ["red","blue","green","white"]
color.insert(2,"pink")
print(color.insert(2,"pink"))
>>>

color = ["red","blue","pink","green","white"]

4. 删除

color = ["red","blue","green","white"]
color.remove("white")  #删除从左到右的第一个值

color = ["red","blue","green","white"]
color.pop()
>>>"white"
>>>color = ["red","blue","green"]

color = ["red","blue","green","white"]
print("del color[red]")
>>>color = ["blue","green","white"]

5. 长度

len(color)
>>>3

6. 包含和循环

>>> 'red' in color
True
>>> 'pink' in color
False

#循环:为什么是“i”？
>>> for i in color:
    print(i)

7. 排序

a = [2,3,4,9,7,15]
a.sort()
print(a.sort（））
>>>a = [2,3,4,7,9,15]

 8. 查询

color = ["red","blue","green","white"]
color.index("blue")
>>>print(color.index("blue"))
>>>1

color = ["red","blue","green","white"]
color.count("red")
>>>1