How to use a 5 or 6 bit integer in Python?

[Glen Wheeler]

On Fri, 19 Dec 2003 03:17:36 GMT, "Rainer Deyke" <rainerd at eldwood.com>
wrote:

>You're trying to solve the wrong problem.  Python caches small integers, so
>you've only got a very small number of distinct integer objects.  This is a
>good thing, because each Python object has a eight byte overhead.
>Introducing a new type wouldn't result in any memory savings.
>

  Thanks.  I had thought as much, but was not totally sure.

>The real overhead comes from the references to those objects.  Each
>reference is four bytes (on 32 bit computers), and there is no way to
>decrease this.  Your best option is to use high level objects that contain
>many integers internally but don't store them as individual Python
>references.  The array module is one choice, Numarray is another.  If
>immutability isn't an issue, you could even use strings (with each character
>treated as an eight bit integer).

  So the references to each integer is what causes the massive
overhead.
  I've read up on Numarray and the array module in the docs, but
didn't see how I could adapt my current program to use these modules
because of how my data is currently organised.
  I have one constantly changing dict with many millions of keys
(tuples of ints) which in turn associates itself with a tuple of ints
and two more dicts.
  Every single container type contains only integers.  Am I correct in
assuming that an array cannot be used as a key for a dictionary?  As
they are mutable?

  Thanks for your help,
  Glen