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 found that using a list comprehension and getting its length was faster than using sum().

According to my tests...

len([p for p in PeopleList if p.Gender == 'F'])

...runs 1.59 times as fast as...

sum(p.Gender == "F" for p in PeopleList)