Better dict of dicts

[Larry Bates]

John Bauman wrote:
> Adam Atlas wrote:
>> On Apr 19, 5:24 pm, Bill Jackson <jack... at hotmail.com> wrote:
>>> I have a dictionary of dictionaries where the keys are typically very
>>> long tuples and repeated in each inner dictionary.  The dictionary
>>> representation is nice because it handles sparseness well...and it is
>>> nice to be able to look up values based on a string rather than a
>>> number.  However, since my keys are quite long, I worry that I am
>>> wasting a lot of memory.
>>
>> I wouldn't worry about it. Try doing hash('string_2') in the
>> interpreter -- the output thereof is what's really being used as the
>> key. It doesn't use up any more memory than the integer 2.
>>
> Are you sure about that? Most dictionaries need to store the actual key,
> in case of a collision, so when you lookup a key they can tell which
> you're really looking for.

Maybe this will help:

http://wiki.python.org/moin/DictionaryKeys

-Larry