- Python中，字典放在花括号{}中的一系列鍵-值對表示
- 擷取與鍵相關的值，依次指定字典名和放在花括号内的鍵
- del語句将相應的鍵-值對徹底删除
- 周遊所有的鍵-值對
user_0 ={
'username':'efermi',
'first':'enrico',
'last':'fermi',
}
for key,value in user_0.items()://編寫用于周遊字典的for循環，聲明兩個變量，用于存儲鍵-值對中的鍵和值
print("\nKey: "+ key)
print("Value:"+ value)
---------------------------------------------------------------------
Key: username
Value:efermi
Key: first
Value:enrico
Key: last
Value:fermi
- 周遊字典中的所有鍵
favorite_languages = {
'jen': 'python',
'sarah': 'c',
'edward': 'ruby',
'phil': 'python',
}
for name in favorite_languages.keys()://方法key()
print(name.title())
------------------------------------------------------
Jen
Sarah
Edward
Phil
- 按順序周遊字典中的所有鍵
favorite_languages = {
'jen': 'python',
'sarah': 'c',
'edward': 'ruby',
'phil': 'python',
}
for name in sorted(favorite_languages.keys()):
print(name.title())
---------------------------------------------------
Edward
Jen
Phil
Sarah
-周遊字典所有值
favorite_languages = {
'jen': 'python',
'sarah': 'c',
'edward': 'ruby',
'phil': 'python',
}
for language in set(favorite_languages.values()):
#values()周遊字典所有值 對包含重複清單調用set()
print(language.title())
-------------------------------------------------------------
C
Ruby
Python
-在字典中存儲字典
users = {
'aeinstein': {
'first': 'albert',
'last': 'einstein',
'location': 'princeton',
},
'mcurie': {
'first': 'marie',
'last': 'curie',
'location': 'paris',
},
}
for username, user_info in users.items():
print("\nUsername: " + username)
full_name = user_info['first'] + " " + user_info['last']
location = user_info['location']
print("\tFull name: " + full_name.title())
print("\tLocation: " + location.title())
---------------------------------------------------------------------------
Username: aeinstein
Full name: Albert Einstein
Location: Princeton
Username: mcurie
Full name: Marie Curie
Location: Paris
課後習題
message = {'first_name':'Lily','last_name':'Z','age':'22','city':'HangZhou'}
print(message['first_name'])
print(message['last_name'])
print(message['age'])
print(message['city'])
--------------------------------------------------------------------------
Lily
Z
22
HangZhou
favorite_num = {'a':'1','b':'2','c':'3','d':'4','e':'5'}
print("a favorite number is "+favorite_num['a']+".")
print("b favorite number is "+favorite_num['b']+".")
print("c favorite number is "+favorite_num['c']+".")
print("d favorite number is "+favorite_num['d']+".")
print("e favorite number is "+favorite_num['e']+".")
-------------------------------------------------------------
a favorite number is 1.
b favorite number is 2.
c favorite number is 3.
d favorite number is 4.
e favorite number is 5.
glossary = {
'string':'A series of characters.',
'comment':'A nnote in a program that the Python interpreter ignores.',
'list':'A collectio of items in a particular order.',
'loop':'Work through a collection of items,one at a time.',
'dictionary':'A collection of Key-value pairs.',
}
word = 'string'
print("\n"+word.title()+": "+glossary[word])
word = 'comment'
print("\n"+word.title()+": "+glossary[word])
word = 'list'
print("\n"+word.title()+": "+glossary[word])
word = 'loop'
print("\n"+word.title()+": "+glossary[word])
word = 'dictionary'
print("\n"+word.title()+": "+glossary[word])
----------------------------------------------------------------------
String: A series of characters.
Comment: A nnote in a program that the Python interpreter ignores.
List: A collectio of items in a particular order.
Loop: Work through a collection of items,one at a time.
glossary = {
'string':'A series of characters.',
'comment':'A nnote in a program that the Python interpreter ignores.',
'list':'A collectio of items in a particular order.',
'loop':'Work through a collection of items,one at a time.',
'dictionary':'A collection of Key-value pairs.',
}
for word , definition in glossary.items():
print("\n"+ word.title()+":"+definition)
--------------------------------------------------------------------------
String:A series of characters.
Comment:A nnote in a program that the Python interpreter ignores.
List:A collectio of items in a particular order.
Loop:Work through a collection of items,one at a time.
Dictionary:A collection of Key-value pairs.
rivers = {
'nile':'rgypt',
'mississippi':'Us',
'fraser':'Canada',
'yangtze':'China',
}
for river,country in rivers.items():
print("The "+river.title()+" flowa through "+country.title()+".")
print("\n The following rivers are included in this data set:")
for river in rivers.keys():
print("- "+river.title())
--------------------------------------------------------------------------
The Nile flowa through Rgypt.
The Mississippi flowa through Us.
The Fraser flowa through Canada.
The Yangtze flowa through China.
The following rivers are included in this data set:
- Nile
- Mississippi
- Fraser
- Yangtze
favorite_languages = {
'jen': 'python',
'sarah': 'c',
'edward': 'ruby',
'phil': 'python',
}
for name, language in favorite_languages.items():
print(name.title() + "'s favorite language is " +
language.title() + ".")
names = ['jen','sarah','ben','lily']
for name in names:
if name in favorite_languages.keys():
print("thank u,"+name.title()+"!")
else:
print("weclome,"+name.title()+"!")
----------------------------------------------------------
Jen's favorite language is Python.
Sarah's favorite language is C.
Edward's favorite language is Ruby.
Phil's favorite language is Python.
thank u,Jen!
thank u,Sarah!
weclome,Ben!
weclome,Lily!
message_01 = {'first_name':'Lily','last_name':'Z','age':'22','city':'HangZhou'}
message_02 = {'first_name':'Ben','last_name':'S','age':'10','city':'ShenZhen'}
message_03 = {'first_name':'Cat','last_name':'F','age':'30','city':'BeiJin'}
peoples = [message_01,message_02,message_03]
for people in peoples:
print(people)
-----------------------------------------------------------------------------------------
{'first_name': 'Lily', 'last_name': 'Z', 'age': '22', 'city': 'HangZhou'}
{'first_name': 'Ben', 'last_name': 'S', 'age': '10', 'city': 'ShenZhen'}
{'first_name': 'Cat', 'last_name': 'F', 'age': '30', 'city': 'BeiJin'}
#Make an empty ;ist to store the pets in.
pets = []
#Make individual pets, and store each one on the list.
pet = {
'animal type':'python',
'name':'john',
'owner':'guido',
'eats':'bugs',
}
pets.append(pet)
pet = {
'animal type':'chicken',
'name':'ben',
'owner':'tiffy',
'eats':'seeds',
}
pets.append(pet)
pet = {
'animal type':'dog',
'name':'peo',
'owner':'eric',
'weight':37,
'eats':'shoes',
}
pets.append(pet)
#dispaly information about each pet
for pet in pets:
print("\nHere's what I know about "+pet['name'].title()+":")
for key,value in pet.items():
print("\t"+key+":"+str(value))
-------------------------------------------------------------------------------
Here's what I know about John:
animal type:python
name:john
owner:guido
eats:bugs
Here's what I know about Ben:
animal type:chicken
name:ben
owner:tiffy
eats:seeds
Here's what I know about Peo:
animal type:dog
name:peo
owner:eric
weight:37
eats:shoes
favorite_places = {
'eric':['bear mountain','death valley','tierra del fuego'],
'erin':['hawaii','iceland'],
'ever':['mt.verstovavua','the playfround','south carolina']
}
for name,places in favorite_places.items():
print("\n"+name.title()+" likes the following places:")
for place in places:
print("-"+place.title())
---------------------------------------------------------------
Eric likes the following places:
-Bear Mountain
-Death Valley
-Tierra Del Fuego
Erin likes the following places:
-Hawaii
-Iceland
Ever likes the following places:
-Mt.Verstovavua
-The Playfround
-South Carolina
favorite_numbers = {
'mandy':[42,17],
'micah':[23,33,44],
'gus':[3,4],
}
for name,numbers in favorite_numbers.items():
print("\n"+name.title()+" likes the following numbers:")
for number in numbers:
print(" "+str(number))
-----------------------------------------------------------------------
Mandy likes the following numbers:
42
17
Micah likes the following numbers:
23
33
44
Gus likes the following numbers:
3
4
cities = {
'santiago':{
'country':'chile',
'population':33333333,
'nearby mountains':'andes',
},
'talkrren':{
'country':'aksd',
'population':4535432445,
'nearby mountains':'skjdjd',
},
'hausdueh':{
'country':'dsdsf',
'populartion':3423544543,
'nearby mountains':'fdsfsd',
},
}
for city ,city_info in cities.items():
country = city_info['country'].title()
population = city_info['country'].title()
mountains = city_info['nearby mountains'].title()
print("\n"+city.title()+" is in "+country +".")
print(" it has a population of about "+str(population)+".")
print("The "+mountains+"mountains are nearby.")
-----------------------------------------------------------------------
Santiago is in Chile.
it has a population of about Chile.
The Andesmountains are nearby.
Talkrren is in Aksd.
it has a population of about Aksd.
The Skjdjdmountains are nearby.
Hausdueh is in Dsdsf.
it has a population of about Dsdsf.
The Fdsfsdmountains are nearby.