Create dictionary with a list as key

Question

If I have a list of numbers and want to add them to an existing dictionary with the value 0. What's the easiest way of doing this? Seems so easy but I can't find any clean way of doing this. For example:

key = [1,2,3]
value = 0
dict  = {}
... one more line of code if possible ...

>>>dict
{(1,2,3):0}

Dictionary keys have to be hashable, lists are not because they're mutable. — Barmar, Mar 12 '20 at 15:56
Your sample output uses a tuple as the key. You can convert the list to a tuple and use it as the key. — Barmar, Mar 12 '20 at 15:57
`key = [1,2,3]` => `key = (1,2,3)` if you know that the key is a tuple just create a tuple. — Jean-François Fabre, Mar 12 '20 at 16:11

score 1 · Answer 1 · answered Mar 12 '20 at 15:58

1

You could change your list to a tuple like this:

key = [1,2,3]
value = 0
d = {tuple(key): value}

>>>d
{(1,2,3):0}

answered Mar 12 '20 at 15:58

GiftZwergrapper

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score 0 · Answer 2 · answered Mar 12 '20 at 15:58

0

Your desired output uses a tuple as the key. So convert the list to a tuple.

d[tuple(key)] = 0

BTW, don't use dict as a variable name, it's the name of a built-in type/function.

answered Mar 12 '20 at 15:58

Barmar

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Create dictionary with a list as key

2 Answers2