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Re: KISS4691, a potentially top-ranked RNG.

From "robin" <robin51@dodo.mapson.com.au>
Newsgroups sci.math, comp.lang.c, comp.lang.fortran, comp.lang.pl1, comp.lang.ada
References <4dae2a4b$0$55577$c30e37c6@exi-reader.telstra.net> <4dbd6e9c$0$12957$892e0abb@auth.newsreader.octanews.com> <925saiFj03U7@mid.individual.net> <4dbe2304$0$12961$892e0abb@auth.newsreader.octanews.com> <iplmk8$2s6$1@gosset.csi.cam.ac.uk>
Subject Re: KISS4691, a potentially top-ranked RNG.
Date 2011-05-23 16:52 +1000
Message-ID <4dda042b$2$67779$c30e37c6@exi-reader.telstra.net> (permalink)

Cross-posted to 5 groups.

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<nmm1@cam.ac.uk> wrote in message news:iplmk8$2s6$1@gosset.csi.cam.ac.uk...

| As those of us with significant experience of portability will
| remember, building fixed sizes into a program is a cardinal
| error.  Sooner or later, you will want to run that code on a
| system with different sizes, and it won't work.

That's because FORTRAN was designed around a word machine,
where float precisions offered were single and/or single and double precision.
That could cause different actions when moving from a 32-bit word machine
to 60/64-bit word machine,

Later languages, including PL/I, were designed bearing in mind
byte machines.  The way in which float precisions are specified
lends itself to portability.  Thus, asking for say, 12 decimal digits
got you about that number of digits, whether the machine offered
32-bit or 60-bit words.  Some machines actually offered decimal
(BCD) floats in hardware,* and asking for 12 decimals got you about
that number of digits.

|  The vast
| majority of clean programs, even in C90, needed NO source
| changes to go from 32 to 64 bits; I have written code that was
| moved to systems with 16, 24, 32, 36, 48, 60, 64 and perhaps
| other sizes, and so have many other people.

Indeed.  (Including doing portable character handling before F77.)

| I accept that Marsaglia's generator is a valid case for using
| fixed-width types, but that is likely to make it very inefficient
| indeed on a system where they are not natural.

I very much doubt that any new machine is going to offer less than 32 bit
integer words ; for some years now the trend has been to machines of
64-bit integers.  Marsaglia's (integer) algorithms will run on such machines,
some possibly with minor alterations, but will not, even if modified,
will not run "inefficiently".

|  Masking is a
| far more portably efficient approach.

_______________
* some still do, in an updated verion of decimal.

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Re: KISS4691, a potentially top-ranked RNG. "robin" <robin51@dodo.mapson.com.au> - 2011-04-28 11:14 +1000
  Re: KISS4691, a potentially top-ranked RNG. "e p chandler" <epc8@juno.com> - 2011-04-28 07:42 -0400
    Re: KISS4691, a potentially top-ranked RNG. Gib Bogle <g.bogle@auckland.ac.nz> - 2011-04-29 12:55 +1200
    Re: KISS4691, a potentially top-ranked RNG. David Bernier <david250@videotron.ca> - 2011-04-28 21:50 -0400
      Re: KISS4691, a potentially top-ranked RNG. Ian Collins <ian-news@hotmail.com> - 2011-04-29 14:09 +1200
        Re: KISS4691, a potentially top-ranked RNG. Eric Sosman <esosman@ieee-dot-org.invalid> - 2011-04-28 23:01 -0400
          Re: KISS4691, a potentially top-ranked RNG. Ian Collins <ian-news@hotmail.com> - 2011-04-29 15:09 +1200
            Re: KISS4691, a potentially top-ranked RNG. Uno <merrilljensen@q.com> - 2011-05-08 00:34 -0700
              Re: KISS4691, a potentially top-ranked RNG. Marni Zollinger <marni@altgreendesigns.com> - 2011-05-10 23:38 -0600
          Re: KISS4691, a potentially top-ranked RNG. nmm1@cam.ac.uk - 2011-04-29 07:15 +0100
        Re: KISS4691, a potentially top-ranked RNG. David Bernier <david250@videotron.ca> - 2011-04-28 23:16 -0400
      Re: KISS4691, a potentially top-ranked RNG. glen herrmannsfeldt <gah@ugcs.caltech.edu> - 2011-04-29 02:34 +0000
        Re: KISS4691, a potentially top-ranked RNG. Uno <Uno@example.invalid> - 2011-04-29 01:04 -0600
          Re: KISS4691, a potentially top-ranked RNG. "robin" <robin51@dodo.mapson.com.au> - 2011-04-30 20:48 +1000
            Re: KISS4691, a potentially top-ranked RNG. Uno <Uno@example.invalid> - 2011-05-04 19:12 -0600
        Re: KISS4691, a potentially top-ranked RNG. Keith Thompson <kst-u@mib.org> - 2011-04-29 08:13 -0700
          Re: KISS4691, a potentially top-ranked RNG. glen herrmannsfeldt <gah@ugcs.caltech.edu> - 2011-04-29 17:41 +0000
            Re: KISS4691, a potentially top-ranked RNG. Keith Thompson <kst-u@mib.org> - 2011-04-29 12:53 -0700
              Re: KISS4691, a potentially top-ranked RNG. Michael Press <rubrum@pacbell.net> - 2011-05-05 16:38 -0700
          Re: KISS4691, a potentially top-ranked RNG. Seebs <usenet-nospam@seebs.net> - 2011-04-29 22:45 +0000
          Re: KISS4691, a potentially top-ranked RNG. "Randy Brukardt" <randy@rrsoftware.com> - 2011-04-29 23:36 -0500
      Re: KISS4691, a potentially top-ranked RNG. Seebs <usenet-nospam@seebs.net> - 2011-04-29 22:43 +0000
    Re: KISS4691, a potentially top-ranked RNG. "robin" <robin51@dodo.mapson.com.au> - 2011-04-29 19:43 +1000
  Re: KISS4691, a potentially top-ranked RNG. Thad Smith <ThadSmith@acm.org> - 2011-05-01 08:31 -0700
    Re: KISS4691, a potentially top-ranked RNG. Ian Collins <ian-news@hotmail.com> - 2011-05-02 07:58 +1200
      Re: KISS4691, a potentially top-ranked RNG. James Kuyper <jameskuyper@verizon.net> - 2011-05-01 20:01 -0400
        Re: KISS4691, a potentially top-ranked RNG. Ian Collins <ian-news@hotmail.com> - 2011-05-02 12:42 +1200
          Re: KISS4691, a potentially top-ranked RNG. James Kuyper <jameskuyper@verizon.net> - 2011-05-01 22:34 -0400
          Re: KISS4691, a potentially top-ranked RNG. glen herrmannsfeldt <gah@ugcs.caltech.edu> - 2011-05-02 02:50 +0000
      Re: KISS4691, a potentially top-ranked RNG. Thad Smith <ThadSmith@acm.org> - 2011-05-01 21:21 -0700
        Re: KISS4691, a potentially top-ranked RNG. nmm1@cam.ac.uk - 2011-05-02 08:31 +0100
          Re: KISS4691, a potentially top-ranked RNG. "robin" <robin51@dodo.mapson.com.au> - 2011-05-23 16:52 +1000
          Re: KISS4691, a potentially top-ranked RNG. "robin" <robin51@dodo.mapson.com.au> - 2011-05-23 14:18 +1000
            Re: KISS4691, a potentially top-ranked RNG. "robin" <robin51@dodo.mapson.com.au> - 2011-05-23 17:20 +1000
          Re: KISS4691, a potentially top-ranked RNG. "robin" <robin51@dodo.mapson.com.au> - 2011-05-23 16:52 +1000
          Re: KISS4691, a potentially top-ranked RNG. "robin" <robin51@dodo.mapson.com.au> - 2011-05-23 16:52 +1000
          Re: KISS4691, a potentially top-ranked RNG. "robin" <robin51@dodo.mapson.com.au> - 2011-05-23 16:53 +1000
            Re: KISS4691, a potentially top-ranked RNG. Georg Bauhaus <rm.dash-bauhaus@futureapps.de> - 2011-05-23 09:16 +0200
              Re: KISS4691, a potentially top-ranked RNG. Ilmari Karonen <usenet2@vyznev.invalid> - 2011-05-26 22:06 +0000
              Re: KISS4691, a potentially top-ranked RNG. "robin" <robin51@dodo.mapson.com.au> - 2011-06-28 17:19 +1000
                Re: KISS4691, a potentially top-ranked RNG. "Vinzent Hoefler" <0439279208b62c95f1880bf0f8776eeb@t-domaingrabbing.de> - 2011-06-28 10:44 +0200
                Re: KISS4691, a potentially top-ranked RNG. Chris H <chris@phaedsys.org> - 2011-06-28 10:19 +0100
                Re: KISS4691, a potentially top-ranked RNG. Georg Bauhaus <rm.dash-bauhaus@futureapps.de> - 2011-06-28 11:14 +0200
                Re: KISS4691, a potentially top-ranked RNG. "robin" <robin51@dodo.mapson.com.au> - 2011-06-28 21:59 +1000
                Re: KISS4691, a potentially top-ranked RNG. Chris H <chris@phaedsys.org> - 2011-06-28 13:16 +0100
                Re: KISS4691, a potentially top-ranked RNG. Peter Flass <Peter_Flass@Yahoo.com> - 2011-06-28 11:44 -0400
                Re: KISS4691, a potentially top-ranked RNG. James Kuyper <jameskuyper@verizon.net> - 2011-06-28 08:33 -0400
                Re: KISS4691, a potentially top-ranked RNG. Georg Bauhaus <rm.dash-bauhaus@futureapps.de> - 2011-06-28 15:53 +0200
                Re: KISS4691, a potentially top-ranked RNG. Brian Salter-Duke <b_duke@bigpond.com.au> - 2011-06-28 22:39 +0000
                Re: KISS4691, a potentially top-ranked RNG. James Kuyper <jameskuyper@verizon.net> - 2011-06-28 08:32 -0400
                Re: KISS4691, a potentially top-ranked RNG. Chris H <chris@phaedsys.org> - 2011-06-28 14:03 +0100
                Re: KISS4691, a potentially top-ranked RNG. James Kuyper <jameskuyper@verizon.net> - 2011-06-28 10:25 -0400
                Re: KISS4691, a potentially top-ranked RNG. Chris H <chris@phaedsys.org> - 2011-06-28 16:01 +0100
                Re: KISS4691, a potentially top-ranked RNG. James Kuyper <jameskuyper@verizon.net> - 2011-06-28 20:20 -0400
                Re: KISS4691, a potentially top-ranked RNG. Michael Press <rubrum@pacbell.net> - 2011-06-29 01:38 -0700
                Re: KISS4691, a potentially top-ranked RNG. Joe Pfeiffer <pfeiffer@cs.nmsu.edu> - 2011-06-28 10:04 -0600
                Re: KISS4691, a potentially top-ranked RNG. Chris H <chris@phaedsys.org> - 2011-06-28 17:36 +0100
                Re: KISS4691, a potentially top-ranked RNG. Joe Pfeiffer <pfeiffer@cs.nmsu.edu> - 2011-06-28 10:51 -0600
                Re: KISS4691, a potentially top-ranked RNG. James Kuyper <jameskuyper@verizon.net> - 2011-06-28 20:27 -0400
                Re: KISS4691, a potentially top-ranked RNG. Joe Pfeiffer <pfeiffer@cs.nmsu.edu> - 2011-06-28 19:00 -0600
                Re: KISS4691, a potentially top-ranked RNG. Phil Carmody <thefatphil_demunged@yahoo.co.uk> - 2011-06-29 19:48 +0300
                Re: KISS4691, a potentially top-ranked RNG. Joe Pfeiffer <pfeiffer@cs.nmsu.edu> - 2011-06-28 10:52 -0600
                Re: KISS4691, a potentially top-ranked RNG. David Bernier <david250@videotron.ca> - 2011-06-28 13:06 -0400
                Re: Wiki "robin" <robin51@dodo.mapson.com.au> - 2011-06-29 10:00 +1000
                Re: Wiki James Kuyper <jameskuyper@verizon.net> - 2011-06-28 20:25 -0400
                Re: Wiki Ivan Shmakov <ivan@gray.siamics.net> - 2011-06-29 16:03 +0700
                Re: Wiki Chris H <chris@phaedsys.org> - 2011-06-30 13:39 +0100
                Re: Wiki Frederick Williams <freddywilliams@btinternet.com> - 2011-07-01 22:15 +0100
                Re: Wiki Joe Pfeiffer <pfeiffer@cs.nmsu.edu> - 2011-06-28 18:52 -0600
                Re: Wiki James Kuyper <jameskuyper@verizon.net> - 2011-06-29 05:52 -0400
                Re: Wiki Peter Flass <Peter_Flass@Yahoo.com> - 2011-06-29 10:12 -0400
                Re: Wiki Joe Pfeiffer <pfeiffer@cs.nmsu.edu> - 2011-06-29 14:29 -0600
                Re: Wiki Dr Nick <3-nospam@temporary-address.org.uk> - 2011-06-29 07:43 +0100
                Re: Wiki Peter Flass <Peter_Flass@Yahoo.com> - 2011-06-29 10:10 -0400
                Re: Wiki Phil Carmody <thefatphil_demunged@yahoo.co.uk> - 2011-06-29 19:42 +0300
                Re: Wiki Chris H <chris@phaedsys.org> - 2011-06-29 18:09 +0100
                Re: Wiki Dr Nick <3-nospam@temporary-address.org.uk> - 2011-06-29 18:48 +0100
                Re: Wiki Peter Flass <Peter_Flass@Yahoo.com> - 2011-06-29 09:50 -0400

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