Adding values with reduce() function from the list of tuples

[deanhystad]

Since reading this thread I've been looking for an example where reduce was a better choice than any other python construct. I did not fine any. Every example I found for reduce() could be written shorter and clearer using a comprehension.

from functools import reduce
from time import time

values = [('A', b) for b in range(10000000)]

start = time()
print(reduce(lambda a, b: a + b[1], values, 0))
print(time() - start)

start = time()
print(sum((value[1] for value in values)))
print(time() - start)

Output:
49999995000000
0.7833819389343262
49999995000000
0.7230224609375

The comprehension is even a tiny bit faster.