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pythondictionarysumkey-value

Columnwise sum in a dictionary

I want to sum all the values by their places.

For example, given:

dict= {"adi":(1,2,4),"simon":(1,7,0),"lus":(3,1,2)}

I want to perform the following operation:

(1+1+3,2+7+1,4+0+2)----> (5,10,6)

How can I accomplish this?

Solution

  • We can zip(*data.values()) to transpose the values in the dictionary, and then we can use sum() and a list comprehension to get our final result:

    [sum(val) for val in zip(*data.values())]

    This outputs:

    [5, 10, 6]

    Note that I'm using data rather than dict as a variable name, as the latter is the name of a built-in. Note also that this relies on the fact that dictionaries preserve insertion order, which is only true on Python 3.7+.