如何在python中将列表转换为计数器对象

Question

I have a list which looks like this:

myList = [('string1', 48), ('string2', 48), ('string3', 18)]

how can I convert this into a counter? I've already this:

newCounter = Counter(myList)

but I seem to still be getting a list

Answer 1

You're definitely not getting a list. You're not getting the Counter you want, because the Counter constructor will count an iterable it's provided instead of treating it as a list of key-value pairs, so turn the list into a dict first to get around that:

counter = Counter(dict(myList))

If you're sure you're getting a list, you have some other bug we can't see.

Answer 2

If you print newCounter you'll be able to see it's already a counter object:

Counter({('string3', 18): 1, ('string1', 48): 1, ('string2', 48): 1})

Also see the type of newCounter :

print type(newCounter)
<class 'collections.Counter'>