파이썬 효율적인 리스트 사용법

리스트 컴프리헨션이 가장 빠르다. 

import time


def time_log(original_fn):
    def wrapper_fn(*args, **kwargs):
        start_time = time.time()
        result = original_fn(*args, **kwargs)
        end_time = time.time()
        print(f"Working Time [{original_fn.__name__}]: {end_time - start_time}")
        return result

    return wrapper_fn


@time_log
def list_append():
    a = list(range(100000))
    a2 = list()
    for i in a:
        a2.append(i * 2)
    print(a2[99999])


@time_log
def list_map():
    a = list(range(100000))
    a2 = list(map(lambda n: n * 2, a))
    print(a2[99999])


@time_log
def list_comprehension():
    a2 = [x * 2 for x in range(100000)]
    print(a2[99999])


list_append()
list_map()
list_comprehension()

199998
Working Time [list_append]: 0.018465518951416016
199998
Working Time [list_map]: 0.018465757369995117
199998
Working Time [list_comprehension]: 0.011977434158325195

 

리스트 컴프리헨션은 a list를 생성하지 않으니 좀 더 공평한 조건으로 비교를 해보자. 

@time_log
def list_append():
    a2 = list()
    for i in range(100000):
        a2.append(i * 2)
    print(a2[99999])


@time_log
def list_map():
    a2 = list(map(lambda n: n * 2, range(100000)))
    print(a2[99999])


@time_log
def list_comprehension():
    a2 = [x * 2 for x in range(100000)]
    print(a2[99999])


list_append()
list_map()
list_comprehension()

199998
Working Time [list_append]: 0.01746678352355957
199998
Working Time [list_map]: 0.017966508865356445
199998
Working Time [list_comprehension]: 0.012975931167602539