Multi dimensional python dictionary

Question

I want to create a multi dimensional dictionary in python so that I can access them using the following notation:

test['SYSTEM']['home']['GET']
test['SYSTEM']['home']['POST']

What would be the easiest way to set these values, in other languages I can do this:

test['SYSTEM']['home']['GET'] = True
test['SYSTEM']['home']['POST'] = False

Have you tried doing that in Python? – kylieCatt Jun 19 '15 at 12:03 — kylieCatt, Jun 19 '15 at 12:03

score 5 · Accepted Answer · answered Jun 19 '15 at 12:05

You can create a recursive collections.defaultdict based structure, like this

>>> from collections import defaultdict
>>> nesteddict = lambda: defaultdict(nesteddict)
>>>
>>> test = nesteddict()
>>> test['SYSTEM']['home']['GET'] = True
>>> test['SYSTEM']['home']['POST'] = False
>>>
>>> test['SYSTEM']['home']['GET']
True
>>> test['SYSTEM']['home']['POST']
False

Whenever you access a key in test, which is not there in it, it will invoke the function passed to nesteddict's argument to create a value for the key.

More details on Autovivification here https://en.wikipedia.org/wiki/Autovivification — user913059, Jun 19 '15 at 14:29

score 1 · Answer 2 · answered Jun 19 '15 at 12:08

1

Instead of using multiple dictionary, you could also use tuples as keys:

my_dict = {}
my_dict[('SYSTEM', 'home', 'GET')] = True

this might or might not be useful in your case.

answered Jun 19 '15 at 12:08

Georg Schölly

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Multi dimensional python dictionary

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