方法：title()单词首字母变为大写，upper()全部字母变为大写，lower()全部字母变为小写
name = "Ada LovelAce" print(name.title()) print(name.upper()) print(name.lower())
Ada Lovelace ADA LOVELACE ada lovelace2.3.2在字符串中使用变量
要在字符串中插入变量的值，可在前引号前加上字母f,再将插入的变量放入花括号内
first_name = "ada"
last_name = "lovelace"
full_name = f"{first_name}{last_name}"
print(f"Hello,{full_name.title()}")
Hello,Adalovelace2.3.3使用制表符或换行符来添加空白
制表符t 换行符n
2.3.4删除空格方法：rstrip()删除右边的空格，lstrip()删除左边的空格，strip()删除两边空格
favorite_language = ' python ' favorite_language.strip()
'python'3.2列表修改、添加、和删除元素
motircyles = ['honda','yamaha','suzuki']
motircyles[1]='ducati'
motircyles.append('添加')
del motircyles[2]
motircyles.insert(2,'插入')
motircyles
['honda', 'ducati', '插入', '添加']3.2.1使用pop()方法
motorcycles = ['honda','yamaha','suzuki'] popped_motorcycle = motorcycles.pop() print(motorcycles) print(popped_motorcycle)
['honda', 'yamaha'] suzuki
motorcycles = ['honda','yamaha','suzuki']
first_owned = motorcycles.pop(0)
print(f"The first motorcycles I owned was a {first_owned.title()}")
The first motorcycles I owned was a Honda只知道要删除元素的值，用方法remove()
motorcycles = ['honda','yamaha','suzuki']
motorcycles.remove('honda')
print(motorcycles)
['yamaha', 'suzuki']3.3组织列表
方法：使用sort()对列表永久排序
cars = ['bmw','audi','toyota','subaru'] cars.sort() #正序 print(cars)
['audi', 'bmw', 'subaru', 'toyota']
cars = ['bmw','audi','toyota','subaru'] cars.sort(reverse=True) #倒序 print(cars)
['toyota', 'subaru', 'bmw', 'audi']
函数：使用sorted()对列表临时排序
cars = ['bmw','audi','toyota','subaru'] print(sorted(cars)) print(cars)
['audi', 'bmw', 'subaru', 'toyota'] ['bmw', 'audi', 'toyota', 'subaru']
cars = ['bmw','audi','toyota','subaru'] print(sorted(cars,reverse=True)) print(cars)
['toyota', 'subaru', 'bmw', 'audi'] ['bmw', 'audi', 'toyota', 'subaru']
方法：reverse()永久性的反转列表
cars = ['bmw','audi','toyota','subaru'] cars.reverse() print(cars)
['subaru', 'toyota', 'audi', 'bmw']
函数：len()可快速获取列表的长度
cars = ['bmw','audi','toyota','subaru'] len(cars)
4第四章 操作列表 使用函数range()
for i in range(1,5):
print(i)
1 2 3 4
numbers = list(range(6)) print(numbers)
[0, 1, 2, 3, 4, 5]第六章 字典
favorite_languages = {
'jen':'python',
'sarah':'c',
'enwar':'ruby',
'phil':'python',
}
language = favorite_languages['sarah'].title()
print(f"Saran's favorite language is {language}")
Saran's favorite language is C
方法get() 调用get()时，如果没有指定第二个参数，且指定的参数不存在，将返回None
alien_0 = {'color':'green','speed':'slow'}
point_value = alien_0.get('points','没有分数')
print(point_value)
没有分数6.3.1遍历所有的键值对
user_0 = {
'username':'efermi',
'first':'enrico',
'last':'fermi'
}
for key,value in user_0.items():
print(f"nKey:{key}")
print(f"Value:{value}")
Key:username Value:efermi Key:first Value:enrico Key:last Value:fermi
favorite_languages = {
'jen':'python',
'sarah':'c',
'enwar':'ruby',
'phil':'python',
}
for name,language in favorite_languages.items():
print(f"{name.title()}'s favorite language is {language.title()}")
Jen's favorite language is Python Sarah's favorite language is C Enwar's favorite language is Ruby Phil's favorite language is Python6.3.2遍历所有的键
favorite_languages = {
'jen':'python',
'sarah':'c',
'enwar':'ruby',
'phil':'python',
}
for name in favorite_languages.keys():
print(name)
jen sarah enwar phil
默认遍历所有的键
favorite_languages = {
'jen':'python',
'sarah':'c',
'enwar':'ruby',
'phil':'python',
}
for name in favorite_languages:
print(name)
jen sarah enwar phil
favorite_languages = {
'jen':'python',
'sarah':'c',
'enwar':'ruby',
'phil':'python',
}
friends = ['phil','sarah']
for name in favorite_languages.keys():
print(f"Hi,{name.title()}")
if name in friends:
language = favorite_languages[name].title()
print(f"{name.title()},I see you love {language} ")
Hi,Jen Hi,Sarah Sarah,I see you love C Hi,Enwar Hi,Phil Phil,I see you love Python
方法keys()并非只能用于遍历：实际上，它返回一个列表，其中包含字典中的所有键
favorite_languages = {
'jen':'python',
'sarah':'c',
'enwar':'ruby',
'phil':'python',
}
if 'earn' not in favorite_languages.keys():
print("Erin,please take our poll!")
Erin,please take our poll!
for name in sorted(favorite_languages.keys()):
print(f"{name.title()},thank you for taking the poll.")
Enwar,thank you for taking the poll. Jen,thank you for taking the poll. Phil,thank you for taking the poll. Sarah,thank you for taking the poll.6.3.4 遍历字典中的所有值
favorite_languages = {
'jen':'python',
'sarah':'c',
'enwar':'ruby',
'phil':'python',
}
for language in favorite_languages.values():
print(language.title())
Python C Ruby Python
favorite_languages = {
'jen':'python',
'sarah':'c',
'enwar':'ruby',
'phil':'python',
}
for language in set(favorite_languages.values()):
print(language.title())
C Ruby Python
set(favorite_languages.values())
{'c', 'python', 'ruby'}
集合中的每一个元素都必须是独一无二的，可使用一对花括号直接创建集合，并在其中用逗号分隔元素，集合不会以特定的顺序存储元素
languages = {'python','ruby','python','c'}
print(languages)
{'c', 'ruby', 'python'}
嵌套
在字典中存储列表
pizza = {
'crust':'thick',
'toppings':['mushrooms','extra cheese'],
}
print(f"You ordered a {pizza['crust']}-crust pizza with the following toppings:")
for topping in pizza['toppings']:
print("f"+topping)
You ordered a thick-crust pizza with the following toppings: mushrooms extra cheese
在字典中存储字典
users = {
'aeinstein':{
'first':'albert',
'last':'einstein',
'location':'princeton',
},
'mcurie':{
'first':'marie',
'last':'curie',
'location':'paris',
},
}
for username,user_info in users.items():
print(f"nUsername:{username}")
full_name = f"{user_info['first']}{user_info['last']}"
location = user_info['location']
print(f"tFull name:{full_name.title()}")
print(f"tLocation:{location.title()}")
Username:aeinstein Full name:Alberteinstein Location:Princeton Username:mcurie Full name:Mariecurie Location:Paris
message = input("Tell")
print(message)
TellHello evertone Hello evertone
