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Re: generate De Bruijn sequence memory and string vs lists

References <CALyJZZVU+j64Jn7fqqzLmwW+KcM=43UMKjo=HW7umnq8MSP2Uw@mail.gmail.com> <lbrf82$fb3$1@ger.gmane.org> <mailman.5903.1390500573.18130.python-list@python.org> <bkemj0F48q8U1@mid.individual.net>
From Vincent Davis <vincent@vincentdavis.net>
Date 2014-01-24 07:20 -0600
Subject Re: generate De Bruijn sequence memory and string vs lists
Newsgroups comp.lang.python
Message-ID <mailman.5938.1390569680.18130.python-list@python.org> (permalink)

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On Fri, Jan 24, 2014 at 2:29 AM, Gregory Ewing
<greg.ewing@canterbury.ac.nz>wrote:

> If all you want is a mapping between a sequence of
> length n and compact representation of it, there's
> a much simpler way: just convert it to a base-k
> integer, where k is the size of the alphabet.
>
> The resulting integer won't be any larger than an
> index into the de Bruijn sequence would be, and
> you can easily recover the original sequence from
> its encoding without needing any kind of lookup
> table.
>

​True, ​the "all you want is a mapping" is not quite true. I actually plan
to plot frequency (the number of times an observed sub sequence overlaps a
value in the De Bruijn sequence) The way the sub sequences overlap is
important to me and I don't see a way go from base-k (or any other base) to
the index location in the De Bruijn sequence. i.e. a decoding algorithm.


Vincent Davis
720-301-3003

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Thread

Re: generate De Bruijn sequence memory and string vs lists Vincent Davis <vincent@vincentdavis.net> - 2014-01-23 11:10 -0600
  Re: generate De Bruijn sequence memory and string vs lists Gregory Ewing <greg.ewing@canterbury.ac.nz> - 2014-01-24 21:29 +1300
    Re: generate De Bruijn sequence memory and string vs lists Vincent Davis <vincent@vincentdavis.net> - 2014-01-24 07:20 -0600
    Re: generate De Bruijn sequence memory and string vs lists Greg Ewing <greg.ewing@canterbury.ac.nz> - 2014-01-25 18:11 +1300

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