# Calculating arithmetic mean (one type of average) in Python

I am not aware of anything in the standard library. However, you could use something like:

`def mean(numbers): return float(sum(numbers)) / max(len(numbers), 1)>>> mean([1,2,3,4])2.5>>> mean([])0.0`

In numpy, there's `numpy.mean()`

.

NumPy has a `numpy.mean`

which is an arithmetic mean. Usage is as simple as this:

`>>> import numpy>>> a = [1, 2, 4]>>> numpy.mean(a)2.3333333333333335`

Use `statistics.mean`

:

`import statisticsprint(statistics.mean([1,2,4])) # 2.3333333333333335`

It's available since Python 3.4. For 3.1-3.3 users, an old version of the module is available on PyPI under the name `stats`

. Just change `statistics`

to `stats`

.