Python编程 从入门到实践-4操作列表下

笔记出处(学习UP主视频记录) https://www.bilibili.com/video/av35698354?p=7

4.4.1 切片

players = ['charles', 'martina', 'michael', 'florence', 'eli']
print (players[0:3])

['charles', 'martina', 'michael']

players = ['charles', 'martina', 'michael', 'florence', 'eli']
print (players[1:4])

['martina', 'michael', 'florence']

players = ['charles', 'martina', 'michael', 'florence', 'eli']
print (players[:4])

['charles', 'martina', 'michael', 'florence']

players = ['charles', 'martina', 'michael', 'florence', 'eli']
print (players[2:])

['michael', 'florence', 'eli']

players = ['charles', 'martina', 'michael', 'florence', 'eli']
print (players[-3:])

['michael', 'florence', 'eli']

4.4.2 遍历切片

players = ['charles', 'martina', 'michael', 'florence', 'eli']

print ("Here are the first three players on my team:")
for player in players[:3]:
    print (player.title())

Here are the first three players on my team:
Charles
Martina
Michael

4.4.3 复制列表

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

print ("My favorite foods are:")
print (my_foods)

print ("
My friend's favorite foods are:")
print (friend_foods)

My favorite foods are:
['pizza', 'falafel', 'carrot cake']

My friend's favorite foods are:
['pizza', 'falafel', 'carrot cake']

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

my_foods.append('cannoli')
friend_foods.append('ice cream')

print ("My favorite foods are:")
print (my_foods)

print ("
My friend's favorite foods are:")
print (friend_foods)

My favorite foods are:
['pizza', 'falafel', 'carrot cake', 'cannoli']

My friend's favorite foods are:
['pizza', 'falafel', 'carrot cake', 'ice cream']

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

my_foods.append('cannoli')
friend_foods.append('ice cream')

print ("My favorite foods are:")
print (my_foods)

print ("
My friend's favorite foods are:")
print (friend_foods)

My favorite foods are:
['pizza', 'falafel', 'carrot cake', 'cannoli', 'ice cream']

My friend's favorite foods are:
['pizza', 'falafel', 'carrot cake', 'cannoli', 'ice cream']

4.5.1 定义元组

dimensions = (200, 50)
print (dimensions[0])
print (dimensions[1])

200
50

dimensions = (200, 50)
dimensions[0] = 250

dimensions[0] = 250
TypeError: 'tuple' object does not support item assignment

4.5.2 遍历元组中的所有值

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

200
50

4.5.3 修改元组变量

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

dimensions = (400, 100)
print ("
Modified dimensions")
for dimension in dimensions:
    print (dimension)

Origin dimensions:
200
50

Modified dimensions
400
100

Caesar卢尚宇

2020年3月12日