Snippet: bitcount()

[Christian Tismer]

Michael Hudson wrote:
> 
> Christian Tismer <tismer at appliedbiometrics.com> writes:
> 
> > > Mini-proposal: len(a) for a long returns the length of the number in
> > > radix-256.
> >
> > bitcount2 is not very slow, see here:

> Still chews gobs of memory though... is there any way of converting
> longs <-> arrays? That'd do the trick, though you'd still end up
> copying, no doubt. Still, I don't think I'm being realistic to talk of
> dealing with numbers so large copying them is an issue in Python. It's
> all just for play, anyway.

No way to do that. Longs are exposed to marshal only at this
time. I guess it could be made visible as a read-only buffer
if we extend the buffer function (i.e. extend longs with
buffer methods), but is it worth it?
The single copy for marshal is very cheap, compared to hex.

if-we-had-this-trick-you-would-have-seen-it-in-the-thread - chris

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