How to calculate moving average in Python 3?

Question

Let\'s say I have a list:

y = [\'1\', \'2\', \'3\', \'4\',\'5\',\'6\',\'7\',\'8\',\'9\',\'10\']

I want to create a function that calculates

Answer 1

There is another solution extending an itertools recipe pairwise(). You can extend this to nwise(), which gives you the sliding window (and works if the iterable is a generator):

def nwise(iterable, n):
    ts = it.tee(iterable, n)
    for c, t in enumerate(ts):
        next(it.islice(t, c, c), None)
    return zip(*ts)

def moving_averages_nw(iterable, n):
    yield from (sum(x)/n for x in nwise(iterable, n))

>>> list(moving_averages_nw(range(1, 11), 5))
[3.0, 4.0, 5.0, 6.0, 7.0, 8.0]

While a relatively high setup cost for short iterables this cost reduces in impact the longer the data set. This uses sum() but the code is reasonably elegant:

Timeit              MP           cfi         *****
--------------------------------------------------------------------------------
10                 4.658        4.959        7.351 
100                5.144        4.070        4.234 
1000               5.312        4.020        3.977 
10000              5.317        4.031        3.966 
100000             5.508        4.115        4.087 
1000000            5.526        4.263        4.202 
10000000           5.632        4.326        4.242