How to subtract values from dictionaries

Question

I have two dictionaries in Python:

d1 = {\'a\': 10, \'b\': 9, \'c\': 8, \'d\': 7}
d2 = {\'a\': 1, \'b\': 2, \'c\': 3, \'e\': 2}

I want to s

Answer 1

Just an update to Haidro answer.

Recommended to use subtract method instead of "-".

d1.subtract(d2)

When - is used, only positive counters are updated into dictionary. See examples below

c = Counter(a=4, b=2, c=0, d=-2)
d = Counter(a=1, b=2, c=3, d=4)
a = c-d
print(a)        # --> Counter({'a': 3})
c.subtract(d)
print(c)        # --> Counter({'a': 3, 'b': 0, 'c': -3, 'd': -6})

Please note the dictionary is updated when subtract method is used.

And finally use dict(c) to get Dictionary from Counter object