P4

1 magicians = ['alice', 'david', 'carolina'] 
2 for magician in magicians: 
3     print(f"{magician.title()}, that was a great trick!")
4     print(f"I can't wait to see your next trick, {magician.title()}.\n")
5     
6 print("Thank you, everyone. That was a great magic show!")

for循环完全是靠缩进来判断代码层次的

1 numbers = list(range(1, 6))
2 print(numbers)
3 [1, 2, 3, 4, 5]

使用range来创建list range(起始值,最大值,步长)  --能得到的是最大值减1

经典处理数字的函数 min() max() sum() 传入list

squares = [value**2 for value in range(1, 11)]
print(squares)

[1, 4, 9, 16, 25, 36, 49, 64, 81, 100]

列表解析 快速创建列表

players = ['charles', 'martina', 'michael', 'florence', 'eli'] 
print(players[0:3])
print("Here are the first three players on my team:")
for player in players[:3]:
    print(player.title())
---------------------------------------
['charles', 'martina', 'michael']
Here are the first three players on my team:
Charles
Martina
Michael

 

 

 切片 只使用列表的一部分数据  [开始索引:终止索引]   

[:终止索引]  如果没有起始索引就从表头开始 

[起始索引:] 如果没有终止索引就到表末 

[-3:] 表示从倒数第三到表尾

my_foods = ['pizza', 'falafel', 'carrot cake'] 
friend_foods = my_foods[:]

 

[:] 复制列表  friend_foods = my_foods不可以俩个是同一个对象

 

元组

 

元组是不可以修改的

dimensions = (200, 50)
for dimension in dimensions:
    print(dimension)
--------------------------------------
200
50

 

访问元组是和访问列表是一样的

只有一个元素的元组应该这样显示 xx = (80,) 末尾要加一个逗号 

不能修改元组的值 但是可以给元组重新赋值

 

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