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Re: StringBuilder Difficulties

From blmblm@myrealbox.com <blmblm.myrealbox@gmail.com>
Newsgroups comp.lang.java.programmer
Subject Re: StringBuilder Difficulties
Date 2011-07-03 01:34 +0000
Organization None
Message-ID <979v96F7epU1@mid.individual.net> (permalink)
References <c4tk07dv1pq7u8k32qd6b7o1brc2rj8r30@4ax.com> <976q3jF3etU2@mid.individual.net> <e9ps07h56utkftkp8fcarm7uhkk5t999le@4ax.com> <9796kgFoijU3@mid.individual.net>

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In article <9796kgFoijU3@mid.individual.net>,
blmblm@myrealbox.com  <blmblm.myrealbox@gmail.com> wrote:
> In article <e9ps07h56utkftkp8fcarm7uhkk5t999le@4ax.com>,
> Gene Wirchenko  <genew@ocis.net> wrote:
> > On 1 Jul 2011 20:47:47 GMT, blmblm@myrealbox.com
> > <blmblm.myrealbox@gmail.com> wrote:
> > 
> > >In article <6cqp07tiug2nu8u6ififvvek1694fkpfi1@4ax.com>,
> > >Gene Wirchenko  <genew@ocis.net> wrote:
> > >> On 30 Jun 2011 20:30:00 GMT, blmblm@myrealbox.com
> > >> <blmblm.myrealbox@gmail.com> wrote:

[ snip ]

> >      Oh, I asked about that.  One apparently can not pass a function
> > pointer parameter as in C.  The ways that were posted involved lookup
> > every time AFIACS and I judged that it might swamp what I was
> > measuring (checking if a character were in a set).  So, to my chagrin,
> > I had to go with cut-and-paste.
> 
> Without experimenting to find out, of course ....  
> 
> It seems to me that virtual method invocations are so common in
> Java that they would be well-optimized.  But if you want to claim
> that the code you eventually hope to produce won't have one, well,
> yeah, that's true, so maybe it matters.  Then again, wouldn't a
> similar argument apply to C with function pointers?  Maybe not.
> I don't seem to be able to think this through as carefully as
> I'd like.
> 
> Anyway, I was curious, so I ran your code and my revision [1], and
> the results were -- surprising [2].  I noticed, by the way, that
> all three of your parse methods make a call to SequentialSearch,
> assigning the result to a variable that apparently isn't used.
> Thinking that *might* be a mistake, I also tried your code and my
> revision with that possibly-extra call removed.

UPDATE:  I just re-read the previous threads and realized that
your code actually calls SequentialSearch in the method that's
supposed to be timing BinarySearch.  Once I fix that ....

> [1] Message-ID: <96k6atFt60U2@mid.individual.net>
> 
> [2] I tried this on several different systems, all Fedora Linux
> running Java 1.6.0_21 but different hardware and different releases
> of Fedora.  

[ snip ]

> Your code was fairly (but not 100%!) consistent in showing
> treeset-based search to be fastest, followed by binary search and
> then sequential search, though sometimes the difference between
> sequential and binary was small.  My code was -- well, this is where
> it's surprising.  On most of the systems where I tried it, treeset
> search was fastest, but sequential search was faster than binary
> search; on one system, however, the order was as for your code.
> Your code was pretty consistently faster than mine, though usually
> not by a lot (less than 1%).

Both programs (yours and mine) now consistently report sequential
search to be faster than binary search.  Weird, but not as weird as
the two being different in that regard ....

[ snip ]

-- 
B. L. Massingill
ObDisclaimer:  I don't speak for my employers; they return the favor.

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Thread

StringBuilder Difficulties Gene Wirchenko <genew@ocis.net> - 2011-06-28 17:54 -0700
  Re: StringBuilder Difficulties Eric Sosman <esosman@ieee-dot-org.invalid> - 2011-06-28 21:29 -0400
    Re: StringBuilder Difficulties Lew <noone@lewscanon.com> - 2011-06-29 00:48 -0400
      Re: StringBuilder Difficulties Gene Wirchenko <genew@ocis.net> - 2011-06-29 12:19 -0700
    Re: StringBuilder Difficulties Gene Wirchenko <genew@ocis.net> - 2011-06-29 12:11 -0700
      Re: StringBuilder Difficulties Eric Sosman <esosman@ieee-dot-org.invalid> - 2011-06-29 22:06 -0400
  Re: StringBuilder Difficulties blmblm@myrealbox.com <blmblm.myrealbox@gmail.com> - 2011-06-29 20:17 +0000
    Re: StringBuilder Difficulties Gene Wirchenko <genew@ocis.net> - 2011-06-29 18:55 -0700
      Re: StringBuilder Difficulties blmblm@myrealbox.com <blmblm.myrealbox@gmail.com> - 2011-06-30 20:30 +0000
        Re: StringBuilder Difficulties Patricia Shanahan <pats@acm.org> - 2011-06-30 14:17 -0700
          Re: StringBuilder Difficulties Eric Sosman <esosman@ieee-dot-org.invalid> - 2011-06-30 21:36 -0400
            Re: StringBuilder Difficulties "John B. Matthews" <nospam@nospam.invalid> - 2011-07-01 01:41 -0400
        Re: StringBuilder Difficulties Gene Wirchenko <genew@ocis.net> - 2011-06-30 14:26 -0700
          Re: StringBuilder Difficulties Steve Sobol <sjsobol@JustThe.net> - 2011-06-30 17:33 -0700
          Re: StringBuilder Difficulties blmblm@myrealbox.com <blmblm.myrealbox@gmail.com> - 2011-07-01 20:47 +0000
            Re: StringBuilder Difficulties Gene Wirchenko <genew@ocis.net> - 2011-07-01 17:29 -0700
              Re: StringBuilder Difficulties rossum <rossum48@coldmail.com> - 2011-07-02 11:36 +0100
              Re: StringBuilder Difficulties Robert Klemme <shortcutter@googlemail.com> - 2011-07-02 12:58 +0200
                Re: StringBuilder Difficulties Gene Wirchenko <genew@ocis.net> - 2011-07-04 07:52 -0700
                Re: StringBuilder Difficulties Robert Klemme <shortcutter@googlemail.com> - 2011-07-04 21:45 +0200
                Re: StringBuilder Difficulties supercalifragilisticexpialadiamaticonormalizeringelimatisticantations <supercalifragilisticexpialadiamaticonormalizeringelimatisticantations@averylongandannoyingdomainname.com> - 2011-07-05 02:06 -0400
                Re: StringBuilder Difficulties markspace <-@.> - 2011-07-05 09:32 -0700
                Re: StringBuilder Difficulties supercalifragilisticexpialadiamaticonormalizeringelimatisticantations <supercalifragilisticexpialadiamaticonormalizeringelimatisticantations@averylongandannoyingdomainname.com> - 2011-07-05 14:13 -0400
                Re: StringBuilder Difficulties markspace <-@.> - 2011-07-05 12:51 -0700
                Re: StringBuilder Difficulties Silvio <silvio@moc.com> - 2011-07-05 23:16 +0200
                Re: StringBuilder Difficulties markspace <-@.> - 2011-07-05 15:08 -0700
                Re: StringBuilder Difficulties Silvio <silvio@moc.com> - 2011-07-06 09:41 +0200
                Re: StringBuilder Difficulties "eye" <eye@mocka.com> - 2011-07-06 09:55 +0000
                Re: StringBuilder Difficulties thoolen <thoolen@tholenbot.thorium> - 2011-07-06 05:37 -0400
                Re: StringBuilder Difficulties "thoolen" <thoolen@tholenbot.thorium> - 2011-07-06 08:43 -0400
                Re: StringBuilder Difficulties thoolen <thoolen@tholenbot.thorium> - 2011-07-06 22:30 -0400
                Re: StringBuilder Difficulties "Stefan Robacki" <noemail@noemail.foobar> - 2011-07-06 00:04 -0400
                Re: StringBuilder Difficulties thoolen <thoolen@tholenbot.thorium> - 2011-07-06 05:45 -0400
                Re: StringBuilder Difficulties thoolen <thoolen@tholenbot.thorium> - 2011-07-06 08:26 -0400
                Re: StringBuilder Difficulties thoolen <thoolen@tholenbot.thorium> - 2011-07-06 22:36 -0400
                Re: StringBuilder Difficulties "tholen@antispam.ham" <tholen@ifa.hawaii.edu> - 2011-07-06 06:09 -0700
                Re: StringBuilder Difficulties supercalifragilisticexpialadiamaticonormalizeringelimatisticantations <supercalifragilisticexpialadiamaticonormalizeringelimatisticantations@averylongandannoyingdomainname.com> - 2011-07-06 22:40 -0400
                Re: StringBuilder Difficulties John Doe <jdoe@usenetlove.invalid> - 2011-07-14 06:50 +0000
                Re: StringBuilder Difficulties supercalifragilisticexpialadiamaticonormalizeringelimatisticantations <supercalifragilisticexpialadiamaticonormalizeringelimatisticantations@averylongandannoyingdomainname.com> - 2011-07-14 02:58 -0400
                Re: StringBuilder Difficulties Jane Doe <jdoe@love.in.d.jungle.invalid> - 2011-07-14 10:20 -0400
                Re: StringBuilder Difficulties thoolen <tholen01@gmail.com> - 2011-07-14 07:33 -0700
                Re: StringBuilder Difficulties Stanimir Stamenkov <s7an10@netscape.net> - 2011-07-05 23:44 +0300
                Re: StringBuilder Difficulties markspace <-@.> - 2011-07-05 14:08 -0700
              Re: StringBuilder Difficulties blmblm@myrealbox.com <blmblm.myrealbox@gmail.com> - 2011-07-02 18:33 +0000
                Re: StringBuilder Difficulties supercalifragilisticexpialadiamaticonormalizeringelimatisticantations <supercalifragilisticexpialadiamaticonormalizeringelimatisticantations@averylongandannoyingdomainname.com> - 2011-07-02 16:56 -0400
                Re: StringBuilder Difficulties blmblm@myrealbox.com <blmblm.myrealbox@gmail.com> - 2011-07-03 01:34 +0000
                Re: StringBuilder Difficulties Patricia Shanahan <pats@acm.org> - 2011-07-02 19:55 -0700
                Re: StringBuilder Difficulties blmblm@myrealbox.com <blmblm.myrealbox@gmail.com> - 2011-07-04 03:32 +0000
                Re: StringBuilder Difficulties Gene Wirchenko <genew@ocis.net> - 2011-07-04 08:04 -0700
                Re: StringBuilder Difficulties blmblm@myrealbox.com <blmblm.myrealbox@gmail.com> - 2011-07-05 19:12 +0000
                Re: StringBuilder Difficulties Gene Wirchenko <genew@ocis.net> - 2011-07-05 14:06 -0700
                Re: StringBuilder Difficulties blmblm@myrealbox.com <blmblm.myrealbox@gmail.com> - 2011-07-05 21:16 +0000
                Re: StringBuilder Difficulties Gene Wirchenko <genew@ocis.net> - 2011-07-05 17:29 -0700
                Re: StringBuilder Difficulties blmblm@myrealbox.com <blmblm.myrealbox@gmail.com> - 2011-07-06 16:59 +0000
                Re: StringBuilder Difficulties supercalifragilisticexpialadiamaticonormalizeringelimatisticantations <supercalifragilisticexpialadiamaticonormalizeringelimatisticantations@averylongandannoyingdomainname.com> - 2011-07-06 19:52 -0400
                Re: StringBuilder Difficulties Patricia Shanahan <pats@acm.org> - 2011-07-06 16:58 -0700
                Re: StringBuilder Difficulties supercalifragilisticexpialadiamaticonormalizeringelimatisticantations <supercalifragilisticexpialadiamaticonormalizeringelimatisticantations@averylongandannoyingdomainname.com> - 2011-07-06 19:52 -0400
                Re: StringBuilder Difficulties supercalifragilisticexpialadiamaticonormalizeringelimatisticantations <supercalifragilisticexpialadiamaticonormalizeringelimatisticantations@averylongandannoyingdomainname.com> - 2011-07-06 21:54 -0400
                Re: StringBuilder Difficulties supercalifragilisticexpialadiamaticonormalizeringelimatisticantations <supercalifragilisticexpialadiamaticonormalizeringelimatisticantations@averylongandannoyingdomainname.com> - 2011-07-06 22:18 -0400
                Re: StringBuilder Difficulties supercalifragilisticexpialadiamaticonormalizeringelimatisticantations <supercalifragilisticexpialadiamaticonormalizeringelimatisticantations@averylongandannoyingdomainname.com> - 2011-07-06 22:41 -0400
                Re: StringBuilder Difficulties blmblm@myrealbox.com <blmblm.myrealbox@gmail.com> - 2011-07-08 17:45 +0000
                Re: StringBuilder Difficulties supercalifragilisticexpialadiamaticonormalizeringelimatisticantations <supercalifragilisticexpialadiamaticonormalizeringelimatisticantations@averylongandannoyingdomainname.com> - 2011-07-06 05:48 -0400
                Re: StringBuilder Difficulties blmblm@myrealbox.com <blmblm.myrealbox@gmail.com> - 2011-07-06 16:59 +0000
                Re: StringBuilder Difficulties Gene Wirchenko <genew@ocis.net> - 2011-07-06 10:56 -0700
                Re: StringBuilder Difficulties blmblm@myrealbox.com <blmblm.myrealbox@gmail.com> - 2011-07-08 17:44 +0000
                Re: StringBuilder Difficulties Gene Wirchenko <genew@ocis.net> - 2011-07-08 11:51 -0700
                Re: StringBuilder Difficulties blmblm@myrealbox.com <blmblm.myrealbox@gmail.com> - 2011-07-10 19:08 +0000
                Re: StringBuilder Difficulties Gene Wirchenko <genew@ocis.net> - 2011-07-11 07:54 -0700
                Re: StringBuilder Difficulties blmblm@myrealbox.com <blmblm.myrealbox@gmail.com> - 2011-07-11 22:37 +0000
                Re: StringBuilder Difficulties Gene Wirchenko <genew@ocis.net> - 2011-07-11 15:52 -0700
                Re: StringBuilder Difficulties supercalifragilisticexpialadiamaticonormalizeringelimatisticantations <supercalifragilisticexpialadiamaticonormalizeringelimatisticantations@averylongandannoyingdomainname.com> - 2011-07-06 08:25 -0400
                Re: StringBuilder Difficulties supercalifragilisticexpialadiamaticonormalizeringelimatisticantations <supercalifragilisticexpialadiamaticonormalizeringelimatisticantations@averylongandannoyingdomainname.com> - 2011-07-06 19:41 -0400
                Re: StringBuilder Difficulties supercalifragilisticexpialadiamaticonormalizeringelimatisticantations <supercalifragilisticexpialadiamaticonormalizeringelimatisticantations@averylongandannoyingdomainname.com> - 2011-07-06 19:58 -0400
                Re: StringBuilder Difficulties supercalifragilisticexpialadiamaticonormalizeringelimatisticantations <supercalifragilisticexpialadiamaticonormalizeringelimatisticantations@averylongandannoyingdomainname.com> - 2011-07-06 21:57 -0400
                Re: StringBuilder Difficulties supercalifragilisticexpialadiamaticonormalizeringelimatisticantations <supercalifragilisticexpialadiamaticonormalizeringelimatisticantations@averylongandannoyingdomainname.com> - 2011-07-06 22:17 -0400
                Re: StringBuilder Difficulties supercalifragilisticexpialadiamaticonormalizeringelimatisticantations <supercalifragilisticexpialadiamaticonormalizeringelimatisticantations@averylongandannoyingdomainname.com> - 2011-07-06 22:44 -0400
                Re: StringBuilder Difficulties Steve Erwin <trollHunter@Usenet.4.usenetizens.org.invalid> - 2011-07-07 12:51 +1000
                Re: StringBuilder Difficulties supercalifragilisticexpialadiamaticonormalizeringelimatisticantations <supercalifragilisticexpialadiamaticonormalizeringelimatisticantations@averylongandannoyingdomainname.com> - 2011-07-06 23:02 -0400
                Re: StringBuilder Difficulties John Doe <jdoe@usenetlove.invalid> - 2011-07-14 06:32 +0000
                Re: StringBuilder Difficulties supercalifragilisticexpialadiamaticonormalizeringelimatisticantations <supercalifragilisticexpialadiamaticonormalizeringelimatisticantations@averylongandannoyingdomainname.com> - 2011-07-14 02:57 -0400
                Re: StringBuilder Difficulties Jane Doe <jdoe@love.in.d.jungle.invalid> - 2011-07-14 10:07 -0400
                Re: StringBuilder Difficulties thoolen <tholen01@gmail.com> - 2011-07-14 07:24 -0700
                Re: StringBuilder Difficulties Gene Wirchenko <genew@ocis.net> - 2011-07-04 07:58 -0700
                Re: StringBuilder Difficulties blmblm@myrealbox.com <blmblm.myrealbox@gmail.com> - 2011-07-05 19:09 +0000
                Re: StringBuilder Difficulties KitKat <kitkat_11697@gmail.example.com> - 2011-07-05 15:15 -0400
                Re: StringBuilder Difficulties blmblm@myrealbox.com <blmblm.myrealbox@gmail.com> - 2011-07-05 20:03 +0000
                Re: StringBuilder Difficulties Gene Wirchenko <genew@ocis.net> - 2011-07-05 14:11 -0700
                Re: StringBuilder Difficulties blmblm@myrealbox.com <blmblm.myrealbox@gmail.com> - 2011-07-06 16:55 +0000
      Re: StringBuilder Difficulties lewbloch <lewbloch@gmail.com> - 2011-07-03 00:08 -0700
        Re: StringBuilder Difficulties Robert Klemme <shortcutter@googlemail.com> - 2011-07-03 12:35 +0200
          Re: StringBuilder Difficulties lewbloch <lewbloch@gmail.com> - 2011-07-04 04:07 -0700
  Re: StringBuilder Difficulties Patricia Shanahan <pats@acm.org> - 2011-06-29 14:38 -0700
    Re: StringBuilder Difficulties Gene Wirchenko <genew@ocis.net> - 2011-06-29 15:00 -0700
      Re: StringBuilder Difficulties Patricia Shanahan <pats@acm.org> - 2011-06-29 15:52 -0700
        Re: StringBuilder Difficulties Gene Wirchenko <genew@ocis.net> - 2011-06-29 18:58 -0700
          Re: StringBuilder Difficulties Patricia Shanahan <pats@acm.org> - 2011-06-29 19:26 -0700
          Re: StringBuilder Difficulties lewbloch <lewbloch@gmail.com> - 2011-07-03 00:11 -0700
  Re: StringBuilder Difficulties Roedy Green <see_website@mindprod.com.invalid> - 2011-06-29 18:32 -0700

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