Python - List of dictionaries all values Summation

Python – List of dictionaries all values Summation

Last Updated : 01 Aug, 2020

Given a list of dictionaries, extract all the values summation.

Input : test_list = [{“Apple” : 2, “Mango” : 2, “Grapes” : 2}, {“Apple” : 2, “Mango” : 2, “Grapes” : 2}]
Output : 12
Explanation : 2 + 2 +…(6-times) = 12, sum of all values.
Input : test_list = [{“Apple” : 3, “Mango” : 2, “Grapes” : 2}, {“Apple” : 2, “Mango” : 3, “Grapes” : 3}]
Output : 15
Explanation : Summation of all values leads to 15.

Method #1 : Using loop

This is brute way in which this task can be performed. In this, we iterate for all the dictionaries from list and then perform sum of all the keys of each dictionary.

Python3

# Python3 code to demonstrate working of 
# List of dictionaries all values Summation
# Using loop
  
# initializing lists
test_list = [{"Gfg" : 6, "is" : 9, "best" : 10}, 
             {"Gfg" : 8, "is" : 11, "best" : 19},
             {"Gfg" : 2, "is" : 16, "best" : 10},
             {"Gfg" : 12, "is" : 1, "best" : 8},
             {"Gfg" : 22, "is" : 6, "best" : 8}]
  
# printing original list
print("The original list : " + str(test_list))
  
res = 0
# loop for dictionaries
for sub in test_list:
    for key in sub:
          
        # summation of each key 
        res += sub[key]
      
# printing result 
print("The computed sum : " + str(res))

Output

The original list : [{'Gfg': 6, 'is': 9, 'best': 10}, {'Gfg': 8, 'is': 11, 'best': 19}, {'Gfg': 2, 'is': 16, 'best': 10}, {'Gfg': 12, 'is': 1, 'best': 8}, {'Gfg': 22, 'is': 6, 'best': 8}]
The computed sum : 148

Method #2 : Using sum() + values() + list comprehension

The combination of above functions can be used as one-liner alternative to solve this problem. In this, summation is performed using sum(), and values( ) is used to extract values of all dictionaries in list.

Python3

# Python3 code to demonstrate working of 
# List of dictionaries all values Summation
# Using sum() + values() + list comprehension
  
# initializing lists
test_list = [{"Gfg" : 6, "is" : 9, "best" : 10}, 
             {"Gfg" : 8, "is" : 11, "best" : 19},
             {"Gfg" : 2, "is" : 16, "best" : 10},
             {"Gfg" : 12, "is" : 1, "best" : 8},
             {"Gfg" : 22, "is" : 6, "best" : 8}]
  
# printing original list
print("The original list : " + str(test_list))
  
res = sum([sum(list(sub.values())) for sub in test_list])
      
# printing result 
print("The computed sum : " + str(res))

Output

The original list : [{'Gfg': 6, 'is': 9, 'best': 10}, {'Gfg': 8, 'is': 11, 'best': 19}, {'Gfg': 2, 'is': 16, 'best': 10}, {'Gfg': 12, 'is': 1, 'best': 8}, {'Gfg': 22, 'is': 6, 'best': 8}]
The computed sum : 148

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