如何在字典中乘以列表元素

Question

I have two Dictionaries as mentioned below, I need to multiply each element in the list of dictionaries with respective element of the list of other dictionary and print result. I have managed to multiply one list, How do I make it dynamic?

dict1 = {0: [1, 1, 0, 1, 1, 0], 1: [1, 0, 1, 1, 1, 0]}

dict2 = { 0: [16, 0, 2, 0, 0, 0], 1: [15, 0, 0, 0, 1, 0]}

result = { 0: [16, 0, 0, 0, 0, 0], 1:[15, 0, 0, 0, 1, 0]}

from operator import mul
result = list( map(mul, dict1[0], dict2[0]) )

Answer 1

You can zip each of the lists together and use a dict comprehension like this:

result = {i :[x*y for x, y in zip(dict1[i], dict2[i])] for i in dict1.keys()}

This assumes that dict1 and dict2 share the same keys

Answer 2

Welcome stack user,

You can use DICT COMPREHENSIONS to do it. No zip required.

from operator import mul

dict1 = {0: [1, 1, 0, 1, 1, 0], 1: [1, 0, 1, 1, 1, 0]}
dict2 = {0: [16, 0, 2, 0, 0, 0], 1: [15, 0, 0, 0, 1, 0]}

result = {key: list(map(mul, dict1[key], dict2[key])) for key in dict1.keys() }

result
{0: [16, 0, 0, 0, 0, 0], 1: [15, 0, 0, 0, 1, 0]}

PEP 274 -- Dict Comprehensions https://www.python.org/dev/peps/pep-0274/

It reads something like: For each key in the list of keys, make a dictionary from key and list(map(mul, dict1[key], dict2[key]))

Hope that helps

dictionary-comprehension