From: Ian Collins <ian-news@hotmail.com>
Subject: Re: KISS4691, a potentially top-ranked RNG.
Date: Fri, 29 Apr 2011 14:09:15 +1200
Date: 2011-04-29T14:09:15+12:00 [thread overview]
Message-ID: <91ukucFq9cU2@mid.individual.net> (raw)
In-Reply-To: <ipd5i2011p@news6.newsguy.com>
On 04/29/11 01:50 PM, David Bernier wrote:
> e p chandler wrote:
>>
>>
>> "robin" wrote in message
>>
>> | So, what is all this? In particular, is there something special about
>> | the value of 3.7 billion?
>>
>>> No, nothing special at all.
>>> The purpose of the exercise is just to confirm that after generating
>>> 1000000000 random numbers, you get the same answer as George does.
>>
>> Alas, I think you are making some strong assumptions about the state of
>> computing in the hereafter.
>>
>
> All we have now are George Marsaglia's posts and writings.
> I know there's now a move on the way to 64-bit processors,
> which I take to mean the x86_64 or AMD64 design/instruction set.
The move happened several years ago (at least on the desktop and server).
> In any case, with an executable compiled with a C compiler,
> there's the function sizeof, which might be useful
> in some cases at run time.
Being pedantic, sizeof is a compile time operator when used with
integral types.
> For example, one could add to main() in C :
>
> printf("the size of an unsigned long in bytes is %d\n", sizeof(unsigned long));
Given the code as written, assert(sizeof(unsigned long) == 4) would be
more use.
> There's also the Itanium architecture and others, and even with a known
> processor, some compiler flags affect the number of bytes for
> some data types, such as "long double" with the -m64 flag
> on Fujitsu SPARC IV with Sun Solaris (--> 16 byte long
> doubles with the -m64 flag).
>
> AFAIK, sizeof(unsigned long) can be relied upon to give the size
> in 8-bit bytes of a C "unsigned long".
sizeof(unsigned long) is by definition the size in (not necessarily 8
bit) bytes of an unsigned long.
> Perhaps some documentation of language, machine, compiler, compiler
> options examples where KISS4691 works as per the Marsaglia
> specs could be helpful as a reference ...
I suggested long ago the code be updated to use fixed width types, thus
removing any ambiguities.
--
Ian Collins
next prev parent reply other threads:[~2011-04-29 2:09 UTC|newest]
Thread overview: 84+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <4dae2a4b$0$55577$c30e37c6@exi-reader.telstra.net>
2011-04-28 1:14 ` KISS4691, a potentially top-ranked RNG robin
2011-04-28 11:42 ` e p chandler
2011-04-29 1:50 ` David Bernier
2011-04-29 2:09 ` Ian Collins [this message]
2011-04-29 3:01 ` Eric Sosman
2011-04-29 3:09 ` Ian Collins
2011-05-08 7:34 ` Uno
2011-05-11 5:38 ` Marni Zollinger
2011-04-29 6:15 ` nmm1
2011-04-29 3:16 ` David Bernier
2011-04-29 2:34 ` glen herrmannsfeldt
2011-04-29 7:04 ` Uno
2011-04-30 10:48 ` robin
2011-05-05 1:12 ` Uno
2011-04-29 15:13 ` Keith Thompson
2011-04-29 17:41 ` glen herrmannsfeldt
2011-04-29 19:53 ` Keith Thompson
2011-05-05 23:38 ` Michael Press
2011-04-29 22:45 ` Seebs
2011-04-30 4:36 ` Randy Brukardt
2011-04-29 22:43 ` Seebs
2011-04-29 9:43 ` robin
2011-05-01 15:31 ` Thad Smith
2011-05-01 19:58 ` Ian Collins
2011-05-02 0:01 ` James Kuyper
2011-05-02 0:42 ` Ian Collins
2011-05-02 2:34 ` James Kuyper
2011-05-02 2:50 ` glen herrmannsfeldt
2011-05-02 4:21 ` Thad Smith
2011-05-02 7:31 ` nmm1
2011-05-23 4:18 ` robin
2011-05-23 7:20 ` robin
2011-05-23 6:52 ` robin
2011-05-23 6:52 ` robin
2011-05-23 6:52 ` robin
2011-05-23 6:53 ` robin
2011-05-23 7:16 ` Georg Bauhaus
2011-06-28 7:19 ` robin
2011-06-28 8:44 ` Vinzent Hoefler
2011-06-28 9:19 ` Chris H
2011-06-28 9:14 ` Georg Bauhaus
2011-06-28 11:59 ` robin
2011-06-28 12:16 ` Chris H
2011-06-28 15:44 ` Peter Flass
2011-06-28 12:33 ` James Kuyper
2011-06-28 13:53 ` Georg Bauhaus
2011-06-28 22:39 ` Brian Salter-Duke
2011-06-28 12:32 ` James Kuyper
2011-06-28 13:03 ` Chris H
2011-06-28 14:25 ` James Kuyper
2011-06-28 15:01 ` Chris H
2011-06-29 0:20 ` James Kuyper
2011-06-29 8:38 ` Michael Press
2011-06-28 16:04 ` Joe Pfeiffer
2011-06-28 16:36 ` Chris H
2011-06-28 16:51 ` Joe Pfeiffer
2011-06-29 0:27 ` James Kuyper
2011-06-29 1:00 ` Joe Pfeiffer
2011-06-29 16:48 ` Phil Carmody
2011-06-28 16:52 ` Joe Pfeiffer
2011-06-28 17:06 ` David Bernier
2011-06-28 21:11 ` Gib Bogle
2011-06-29 4:47 ` Mart van de Wege
2011-07-02 6:49 ` Gib Bogle
2011-07-02 15:59 ` Mart van de Wege
2011-07-02 21:57 ` Gib Bogle
2011-06-29 7:36 ` nmm1
2011-06-29 9:58 ` Georg Bauhaus
[not found] <a82cebe3-cdb9-48af-8080-bca935eeb9b1@l14g2000yql.googlegroups.com>
2010-07-25 0:49 ` Gene
2010-07-26 2:50 ` robin
2010-07-27 5:46 ` robin
2010-07-30 10:46 ` Uno
2010-08-03 10:41 ` robin
2010-08-03 17:15 ` James Waldby
2010-08-03 17:35 ` Dann Corbit
2010-08-03 20:34 ` Peter Flass
2010-08-04 4:20 ` Uno
2010-08-04 8:31 ` robin
2010-08-04 7:56 ` robin
2010-08-05 21:07 ` Uno
2010-08-06 10:11 ` robin
2010-08-09 14:52 ` mecej4
[not found] ` <i2fir2$op4$1@speranza.aioe.org>
2010-07-27 10:19 ` robin
2010-07-30 8:33 ` Uno
replies disabled
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox