Path: csiph.com!v102.xanadu-bbs.net!xanadu-bbs.net!feeder.erje.net!eu.feeder.erje.net!news.internetdienste.de!weretis.net!feeder1.news.weretis.net!news.albasani.net!news.stack.nl!newsfeed.xs4all.nl!newsfeed1a.news.xs4all.nl!xs4all!newsgate.cistron.nl!newsgate.news.xs4all.nl!post.news.xs4all.nl!not-for-mail Return-Path: X-Original-To: python-list@python.org Delivered-To: python-list@mail.python.org X-Spam-Status: OK 0.011 X-Spam-Evidence: '*H*': 0.98; '*S*': 0.00; 'true,': 0.05; 'sub': 0.09; 'subject:string': 0.09; 'algorithm.': 0.16; 'example?': 0.16; 'from:addr:greg.ewing': 0.16; 'from:name:greg ewing': 0.16; 'message-id:@canterbury.ac.nz': 0.16; 'overlaps': 0.16; 'received :conversion-daemon.it.canterbury.ac.nz': 0.16; 'sequence.': 0.16; 'subsequences': 0.16; 'index': 0.16; 'wrote:': 0.18; 'trying': 0.19; 'seems': 0.21; '(the': 0.22; 'to:name:python- list@python.org': 0.22; 'header:User-Agent:1': 0.23; 'greg': 0.24; '(or': 0.24; 'appear': 0.29; 'received:132': 0.31; 'quite': 0.32; 'maybe': 0.34; 'subject:lists': 0.35; 'there': 0.35; 'i.e.': 0.36; 'sequence': 0.36; 'should': 0.36; 'whatever': 0.38; 'to:addr :python-list': 0.38; 'explain': 0.39; 'to:addr:python.org': 0.39; 'skip:u 10': 0.60; 'received:nz': 0.60; "you're": 0.61; 'times': 0.62; 'more': 0.64; 'header:In-reply-to:1': 0.84; 'observed': 0.84 Date: Sat, 25 Jan 2014 18:11:38 +1300 From: Greg Ewing Subject: Re: generate De Bruijn sequence memory and string vs lists In-reply-to: To: "python-list@python.org" MIME-version: 1.0 Content-type: text/plain; charset=ISO-8859-1; format=flowed Content-transfer-encoding: 7bit X-Accept-Language: en-us, en User-Agent: Mozilla Thunderbird 1.0.5 (Macintosh/20050711) References: X-BeenThere: python-list@python.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: General discussion list for the Python programming language List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Newsgroups: comp.lang.python Message-ID: Lines: 20 NNTP-Posting-Host: 2001:888:2000:d::a6 X-Trace: 1390626709 news.xs4all.nl 2830 [2001:888:2000:d::a6]:50582 X-Complaints-To: abuse@xs4all.nl Xref: csiph.com comp.lang.python:64721 Vincent Davis wrote: > 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. So the order or position in which the subsequences appear in the de Bruijn sequence is important? Can you explain more about what you're trying to do? Maybe give a scaled-down example? Whatever it is, it seems like there should be a more efficient way than materialising the whole umpteen-gigabyte sequence. -- Greg