Python | Sum values for each key in nested dictionary

Given a nested dictionary and we have to find sum of particular value in that nested dictionary. This is basically useful in cases where we are given a JSON object or we have scraped a particular page and we want to sum the value of a particular attribute in objects.

Code #1: Find sum of sharpness values using sum() function

# Python code to find sum values within nested dictionaries
weapons = {'': None, 'sword': { 'steel': 151,
                                'sharpness': 100,
                                'age': 2,},

                     'arrow': {'steel': 120,
                               'sharpness': 205,
                               'age': 1,}}

sumValue1 = sum(d['sharpness'] for d in weapons.values() if d)
sumValue2 = sum(d['steel'] for d in weapons.values() if d)

print(sumValue1)
print(sumValue2)

Output:

305
271

Code #2 : Using Iteration to convert it into key:value pair.

# Python code to find sum values within nested dictionaries

weapons = {'': None, 'sword': { 'steel': 151,
                                'sharpness': 100,
                                'age': 2,},

                     'arrow': {'steel': 120,
                               'sharpness': 205,
                               'age': 1,}}

sum = 0

# iterating key value pair
for key ,value in weapons.items():

    if value and 'sharpness' in value.keys():
        # Adding value of sharpness to sum
        sum += value['sharpness']

# printing sum
print(sum)

Output:

305