From mboxrd@z Thu Jan 1 00:00:00 1970 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on polar.synack.me X-Spam-Level: * X-Spam-Status: No, score=1.4 required=5.0 tests=BAYES_00,FORGED_GMAIL_RCVD, FORGED_MUA_MOZILLA,FREEMAIL_FROM autolearn=no autolearn_force=no version=3.4.4 X-Google-Thread: 103376,d04d2547435a643e X-Google-NewGroupId: yes X-Google-Attributes: gida07f3367d7,domainid0,public,usenet X-Google-Language: ENGLISH,ASCII-7-bit Received: by 10.68.191.225 with SMTP id hb1mr12637984pbc.5.1339942488890; Sun, 17 Jun 2012 07:14:48 -0700 (PDT) Path: l9ni61286pbj.0!nntp.google.com!news2.google.com!goblin3!goblin.stu.neva.ru!news.tu-darmstadt.de!news.belwue.de!rz.uni-karlsruhe.de!feed.news.schlund.de!schlund.de!news.online.de!not-for-mail From: Martin Trenkmann Newsgroups: comp.lang.ada Subject: Re: True or False ? Date: Sun, 17 Jun 2012 16:14:48 +0200 Organization: 1&1 Internet AG Message-ID: References: <17029032-5398-4754-8a85-116d595ce59c@googlegroups.com> <87haual1o2.fsf@ludovic-brenta.org> <67e507a5-940f-4168-becb-0fd614709bea@googlegroups.com> NNTP-Posting-Host: erft-5d80a2ba.pool.mediaways.net Mime-Version: 1.0 X-Trace: online.de 1339942488 13048 93.128.162.186 (17 Jun 2012 14:14:48 GMT) X-Complaints-To: abuse@einsundeins.com NNTP-Posting-Date: Sun, 17 Jun 2012 14:14:48 +0000 (UTC) User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:10.0.4) Gecko/20120510 Icedove/10.0.4 In-Reply-To: <67e507a5-940f-4168-becb-0fd614709bea@googlegroups.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Date: 2012-06-17T16:14:48+02:00 List-Id: On 06/17/2012 12:35 PM, adacrypt wrote: > On Sunday, June 17, 2012 10:37:17 AM UTC+1, Ludovic Brenta wrote: >> Austin writes on comp.lang.ada: >>> Do you know if these sort programs are used in real world programming >>> today ? >> >> In our two-million-line mission-critical software we use heap sort and >> tree sort but not quick sort. >> >> -- >> Ludovic Brenta. > > Many thanks. > > I have never heard of heap save - is this to be found in academic books? > I'm taking it then that there has not been any huge advance in sorting methods over the past twenty years. > > Could I pick your brains a bit further. > > My scheme is ideal for accessing vast programs of millions of lines of source code like you mentioned - I tag every variable as it is being keyed in at the outset (at creation time) and then disable it until it is needed (I comment it out ) and if I do need it I simply uncomment it for sorting by a specially developed sorting method. The tags can be stored up front or even stored in a file in memory for systematic calling by the main program > > Perhaps you would have a look at this new method later when I go public. > > Question - would it call it a big asset to improve on sorting methods? - given that there is so much computer power available to day - poor or even bad methods are getting by without notice? > > Many thanks for your help again. > > Regards - Austin. > Have you done an extensive research of sorting algorithms [1] before inventing your scheme or any comparison regarding best/avg/worst case runtime complexity? I think there is still much research in this area going on and depending on the real use case many hybrid algorithms exist. For example the C++ std::sort from GCC uses intosort [2] which is a hybrid of quicksort and heapsort. Python and Java 7, as far as I know, use timsort [3], a hybrid of merge sort and insertion sort. So I would be careful stating that "classroom" algorithms are not used in industry. Anyway, the description of your scheme is not clear to me, but it reminds me a bit of counting sort [4], just to be sure not to reinvent the wheel. Regards -- Martin Trenkmann [1] http://en.wikipedia.org/wiki/Sorting_algorithm [2] http://en.wikipedia.org/wiki/Introsort [3] http://en.wikipedia.org/wiki/Timsort [4] http://en.wikipedia.org/wiki/Counting_sort