Python – Remove Dictionaries with Matching Values with K Key

Given two dictionary lists, remove all the dictionaries which have similar value of K key from other dictionary list.

Input : test_list = [{‘Gfg’ : 3, “is” : 3, “best” : 9}, 
{‘Gfg’ : 8, “is” : 4, “best” : 2}, 
{‘Gfg’ : 9, “is” : 2, “best” : 4}, 
{‘Gfg’ : 8, “is” : 10, “best” : 3}, 
{‘Gfg’ : 7, “is” : 1, “best” : 7}], check_list = [{‘Gfg’ : 8, “Best” : 1}, {“Best” : 2, “Gfg” : 7}], K = “Gfg” 
Output : [{‘Gfg’: 3, ‘is’: 3, ‘best’: 9}, {‘Gfg’: 9, ‘is’: 10, ‘best’: 3}] 
Explanation : All dictionaries with “Gfg”‘s value as 8 or 7 is removed.

Input : test_list = [{‘Gfg’ : 3, “is” : 3, “best” : 9}, 
{‘Gfg’ : 8, “is” : 4, “best” : 2}], check_list = [{‘Gfg’ : 8, “Best” : 1}, {“Best” : 2, “Gfg” : 7}], K = “Gfg” 
Output : [{‘Gfg’: 3, ‘is’: 3, ‘best’: 9}] 
Explanation : All dictionaries with “Gfg”‘s value as 8 or 7 is removed. 

Approach: Using list comprehension + dictionary comprehension

In this, we perform tasks of getting a set of elements using dictionary comprehension, and then a new list is constructed using list comprehension by testing K key’s values absence in the constructed set of values.

The whole task is conducted in two steps, 

• All the unique values are extracted from check_list corresponding to key K using set().
• Each dictionary in test list is checked for key K‘s value, if it is present in set created in first step, then that dictionary is omitted in result, else dictionary is added as result.

Python3

# Python3 code to demonstrate working of
# Remove Dictionaries with Matching Values with K Key
# Using dictionary comprehension + list comprehension

# initializing list
test_list = [{'Gfg': 3, "is": 3, "best": 9},
             {'Gfg': 8, "is": 4, "best": 2},
             {'Gfg': 1, "is": 2, "best": 4},
             {'Gfg': 9, "is": 10, "best": 3},
             {'Gfg': 7, "is": 1, "best": 7}]

# printing original list
print("The original list is : " + str(test_list))

# initializing check dictionary list
check_list = [{'Gfg': 8, "Best": 1}, {"Best": 2, "Gfg": 7}]

# initializing Key
K = "Gfg"

# getting set of values
temp = {sub[K] for sub in check_list}

# checking for value occurrence in test dictionary using in
# filtering only with no matching values
res = [sub for sub in test_list if sub[K] not in temp]

# printing result
print("Dictionary list after removal : " + str(res))

Output:

The original list is : [{‘Gfg’: 3, ‘is’: 3, ‘best’: 9}, {‘Gfg’: 8, ‘is’: 4, ‘best’: 2}, {‘Gfg’: 1, ‘is’: 2, ‘best’: 4}, {‘Gfg’: 9, ‘is’: 10, ‘best’: 3}, {‘Gfg’: 7, ‘is’: 1, ‘best’: 7}] Dictionary list after removal : [{‘Gfg’: 3, ‘is’: 3, ‘best’: 9}, {‘Gfg’: 1, ‘is’: 2, ‘best’: 4}, {‘Gfg’: 9, ‘is’: 10, ‘best’: 3}]

Time Complexity: O(n)
Auxiliary Space: O(1)