Python Count Elements in a List of Objects with Matching Attributes

Question

I am trying to find a simple and fast way of counting the number of Objects in a list that match a criteria. e.g.

class Person:
    def __init__(self, Name, Age,         


        

Answer 1

I prefer this:

def count(iterable):
    return sum(1 for _ in iterable)

Then you can use it like this:

femaleCount = count(p for p in PeopleList if p.Gender == "F")

which is cheap (doesn't create useless lists etc) and perfectly readable (I'd say better than both sum(1 for … if …) and sum(p.Gender == "F" for …)).