Benchmark class generator vs function generator

gistfile1.txt

# coding: utf-8

import time
import operator as op

import numpy as np

# equivalent generators

def foo(n):
    i = -1
    while i < n:
        i += 1
        yield i

class Foo(object):
    def __iter__(self):
        return self
    def __init__(self, n):
        self.i = -1
        self.n = n
    def next(self):
        if self.i < self.n:
            self.i += 1
            return self.i
        else:
            raise StopIteration

def tic(n):
    t0 = time.time()
    reduce(op.add, foo(n))
    return time.time() - t0

def Tic(n):
    t0 = time.time()
    reduce(op.add, Foo(n))
    return time.time() - t0

# measure each
ns = (10**(np.random.rand(5000)*4 + 1)).astype(int)
x, y = map(tic, ns), map(Tic, ns)

# compute ratio
yox = np.array(y)/np.array(x)
yox = yox[np.isfinite(yox)]

print np.median(yox)

# -> 1.58 on my machine