Python - Sort Dictionary List by Key's ith Index value

Python – Sort Dictionary List by Key’s ith Index value

Last Updated : 30 Aug, 2020

Given List of dictionaries, sort dictionaries on basis of Key’s ith index value

Input : [{“Gfg” : “Best”, “for” : “Geeks”}, {“Gfg” : “Good”, “for” : “Me”}, {“Gfg” : “Better”, “for” : “All”}], K = “Gfg”, i = 1
Output : [{‘Gfg’: ‘Best’, ‘for’: ‘Geeks’}, {‘Gfg’: ‘Better’, ‘for’: ‘All’}, {‘Gfg’: ‘Good’, ‘for’: ‘Me’}]
Explanation : Sort in order of e = e < o, as 1st index element of "Gfg"'s value.
Input : [{“Gfg” : “Best”, “for” : “Geeks”}, {“Gfg” : “Good”, “for” : “Me”}, {“Gfg” : “Better”, “for” : “All”}], K = “Gfg”, i = 0
Output : [{‘Gfg’: ‘Best’, ‘for’: ‘Geeks’}, {‘Gfg’: ‘Better’, ‘for’: ‘All’}, {‘Gfg’: ‘Good’, ‘for’: ‘Me’}]
Explanation : Sort in order of B = B < G, as 1st index element of "Gfg"'s value.

Method #1 : Using sort() + lambda

The combination of above functions can be used to solve this problem. In this, we perform task of sorting using sort() and lambda function in “key” parameter drives condition.

Python3

# Python3 code to demonstrate working of 
# Sort Dictionary List by Key's ith Index value
# Using sort() + lambda
  
# initializing lists
test_list = [{"Gfg" : "Best", "for" : "Geeks"},
             {"Gfg" : "Good", "for" : "Me"},
             {"Gfg" : "Better", "for" : "All"}]
  
# printing original list
print("The original list : " + str(test_list))
  
# initializing K 
K = "Gfg"
  
# initializing i 
i = 2
  
# using sort to perform sort(), lambda
# function drives conditions
res = sorted(test_list, key = lambda sub: sub[K][i])
  
# printing result 
print("List after sorting : " + str(res))

Output

The original list : [{‘Gfg’: ‘Best’, ‘for’: ‘Geeks’}, {‘Gfg’: ‘Good’, ‘for’: ‘Me’}, {‘Gfg’: ‘Better’, ‘for’: ‘All’}]
List after sorting : [{‘Gfg’: ‘Good’, ‘for’: ‘Me’}, {‘Gfg’: ‘Best’, ‘for’: ‘Geeks’}, {‘Gfg’: ‘Better’, ‘for’: ‘All’}]

Method #2 : Using sort() + lambda + get()

The combination of above functions can also solve this problem. This is just a slight variation to above method. In this, we use get() to avoid chances of key not present in particular record.

Python3

# Python3 code to demonstrate working of 
# Sort Dictionary List by Key's ith Index value
# Using sort() + lambda + get()
  
# initializing lists
test_list = [{"Gfg" : "Best", "for" : "Geeks"},
             {"Gfg" : "Good", "for" : "Me"},
             {"Gfg" : "Better", "for" : "All"}]
  
# printing original list
print("The original list : " + str(test_list))
  
# initializing K 
K = "Gfg"
  
# initializing i 
i = 2
  
# using sort to perform sort(), lambda
# function drives conditions, get() used to 
# avoid missing key error
res = sorted(test_list, key = lambda sub: sub.get(K)[i])
  
# printing result 
print("List after sorting : " + str(res))

Output

The original list : [{‘Gfg’: ‘Best’, ‘for’: ‘Geeks’}, {‘Gfg’: ‘Good’, ‘for’: ‘Me’}, {‘Gfg’: ‘Better’, ‘for’: ‘All’}]
List after sorting : [{‘Gfg’: ‘Good’, ‘for’: ‘Me’}, {‘Gfg’: ‘Best’, ‘for’: ‘Geeks’}, {‘Gfg’: ‘Better’, ‘for’: ‘All’}]

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