Dictonary comphrension of another dictonary to calcualte average of list values

Question

I have a dictonary like -

d = {'a': [1, 2, 3], 'b': [4, 9], 'c': [1, 3, 9, 8]...}

I want to have a new dictonary which will be

r = {'a': 2, 'b': 6.5, 'c': 5.25}

which are average of list items. I want to do that in a dictonary comprehension code.

Please repeat [on topic](https://stackoverflow.com/help/on-topic) and [how to ask](https://stackoverflow.com/help/how-to-ask) from the [intro tour](https://stackoverflow.com/tour). “Show me how to solve this coding problem” is not a Stack Overflow issue. We expect you to make an honest attempt, and *then* ask a *specific* question about your algorithm or technique. Stack Overflow is not intended to replace existing documentation and tutorials. Each of the steps is a trivial browser search: iterate over a dict, compute a mean, store the value in a new dict. — Prune, Jun 23 '21 at 20:26
@Prune I got it. I was not able to picturise how to do the code. — Anirban Nag 'tintinmj', Jun 23 '21 at 21:13

Green Cloak Guy · Accepted Answer · 2021-06-23T20:25:44.333

3

r = {
     k: sum(v) / len(v) 
     for (k, v) in d.items()
}
# {'a': 2.0, 'b': 6.5, 'c': 5.25}

edited Jun 23 '21 at 20:25

answered Jun 23 '21 at 20:23

Green Cloak Guy

1

That's the most perfect code I've ever seen in my life. – enzo Jun 23 '21 at 20:25
Thanks, I used `mean()` function. – Anirban Nag 'tintinmj' Jun 23 '21 at 21:13

1 Answers1