generate De Bruijn sequence memory and string vs lists

[Vincent Davis]

On 1/23/14, 10:18 AM, Dave Angel wrote:
> (something about your message seems to make it unquotable)

Not sure why the message was not quotable. I sent it using gmail.

On 1/23/14, 10:18 AM, Dave Angel wrote:
> 64gig is 4^18, so you can forget about holding a string of size 4^50

I guess I will have to buy more memory or be happy with less, 4**17 would
be ok.

On 1/23/14, 10:18 AM, Dave Angel wrote:
> If memory size is your issue,  why not make the function a
>   generator,  by replacing the append with a yield?

I plan to use the sequence as an index to count occurrences of sequences of
length n. A generator is equivalent to using itertools.permutations (i
think that the right itertool). My thought is that I don't have to store
each individual (sub)sequence since the De Brujin sequence contains all of
them. i.e. it is a compact representation of every sequence generated by
itertools.permutations.


Vincent Davis



On Thu, Jan 23, 2014 at 10:18 AM, Dave Angel <davea at davea.name> wrote:
>
>  Vincent Davis <vincent at vincentdavis.net> Wrote in message:
> >
> (something about your message seems to make it unquotable)
>
> 64gig is 4^18, so you can forget about holding a string of size 4^50
>
> If memory size is your issue,  why not make the function a
>  generator,  by replacing the append with a yield?
>
>
> --
> DaveA
>
> --
> https://mail.python.org/mailman/listinfo/python-list
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