Dictionary data type ---

Create dictionary

dict = { 
    'role 1': 'Suminoe Azure', 
    'role' 2 ':' Ultimately ', 
    ' role 3 '' inu our ' 
} 
print (dict)

Add elements

dict = {
    'role 1':'abeno seme',
    'role 2':'kagela',
    'role 3':'inu kami'
}
print(dict)

dict['role 4'] = '大天狗'

print(dict)

Removing elements

Use pop () method

dict = {
    'role 1':'abeno seme',
    'role 2':'kagela',
    'role 3':'inu kami'
}
print(dict)

dict.pop('role 1')#标准方法

print(dict)

Use del

dict = {
    'role 1':'abeno seme',
    'role 2':'kagela',
    'role 3':'inu kami'
}
print(dict)

del dict['role 2']

print(dict)

Use popitem () method

 

= {dict 
    'Role. 1': 'Abeno Seme', 
    'Role 2': 'kagela', 
    'Role. 3': 'INU Kami' 
} 
print (dict) 

dict.popitem () # randomly deleted, additional parameters can not 

print ( dict)

Modify elements

dict = {
    'role 1':'abeno seme',
    'role 2':'kagela',
    'role 3':'inu kami'
}
print(dict)

dict['role 3'] = "犬神"

print(dict)

View element

dict = { 
    'Role. 1': 'Abeno Seme', 
    'Role 2': 'kagela', 
    'Role. 3': 'INU Kami' 
} 

Print ( 'Role. 1' in dict) # standard usage, key 'role 1' whether there exists returns True, there is no return Fales 
Print (dict.get ( 'Role. 1')) # is not given, there is a return value, there is no return None 
# and get () different 
print (dict [ 'role 3' ]) # return value exists 
print (dict [ 'role 4' ]) # error does not exist

Multi-level dictionary

= {the MENU 
    "barbecue": { 
        "beef": [ "cow streaky", "cow rib"], 
        "lamb": [ "Kebab", "big fat kidneys"], 
        "fish": [ "grilled salmon head "," roast saury "] 
    }, 
    " sushi ": { 
        " sushi ": [" salmon sushi "," tuna sushi "], 
        " sushi ship ": [" salmon ship "," ship tuna " ], 
        "sashimi": [ "sashimi tuna", "red shell sashimi"] 
    }, 
    "beverage": { 
        "wine": [ "Bordeaux", "Cabernet Sauvignon"], 
        "beer": [ "Asahi", "Kirin"], 
        "sake": [ "The pine", "burning taro"] 
    } 
}

other

= {dict 
    'Role. 1': 'Abeno Seme', 
    'Role 2': 'kagela', 
    'Role. 3': 'INU Kami' 
} 
# print value 
Print (dict.values ()) 

# print key 
print (dict. Keys ()) 

#setdefault: have return value, put the value of the parameter is not set to the default 
dict.setdefault ( 'role 4', 'vampire Ji') 
Print (dict) 
dict.setdefault ( 'Role 2', 'God Le ') 
Print (dict) 

#update 
Print (dict) 
B = {. 1: 2,3:. 4, "Role 2": "Kagura"} 
dict.update (B) 
Print (dict) 

#items dictionary to convert a collection of 
print (dict.items ())

Circulation dictionary

method 1

dict = {
    'role 1':'abeno seme',
    'role 2':'kagela',
    'role 3':'inu kami'
}

for i in dict:
    print(i,dict[i])

Method 2

 

= {dict 
    'Role. 1': 'Abeno Seme', 
    'Role 2': 'kagela', 
    'Role. 3': 'INU Kami' 
} 

for K, V in dict.items (): first dictionary into a list # when large amount of data, inefficient 
    print (k, v)