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Re: LC53, a respectable random generator?

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Albert van der Horst wrote:
> It sounds like you have a whole machinery in place to tests rng's.
> Would you mind adding LC53 to the list?
> 
> \ Comma for clarity, not a double number.
> : LC53  -5 um* -333,333,333 + nip ;

Hm, wasn't Hugh's LC53

: lc53  -333333333 um* -5 um/mod drop ;

?  Don't make Hugh look more stupid than he actually is ;-).

The linear congruent random number generator in Gforth is a mod 2^n 
generator, which has the known (and pretty awful) weakness that the least n 
bits have a period of 2^n each.  LC53 does not have this particular 
weakness, because it uses a prime (2^32-5) as modulus.  In so far, there's 
nothing fundamentally wrong with LC53, other than linear congruent 
generators just can't be that good.

I took the opportunity to replace the standard random number generator in 
Gforth with one based on our new hash function, which uses a combination of 
multiplication, rotate, add, and xor as primitives.  This has a 128 bit 
state, and should survive stringent tests (SmallCrush already passed and 
RabbitFile on a 8MB sample, too).

-- 
Bernd Paysan
"If you want it done right, you have to do it yourself"
http://bernd-paysan.de/

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LC53, a respectable random generator? albert@spenarnc.xs4all.nl (Albert van der Horst) - 2013-11-23 16:25 +0000
  Re: LC53, a respectable random generator? hughaguilar96@yahoo.com - 2013-11-23 17:34 -0800
    Re: LC53, a respectable random generator? hughaguilar96@yahoo.com - 2013-11-23 19:03 -0800
    Re: LC53, a respectable random generator? albert@spenarnc.xs4all.nl (Albert van der Horst) - 2013-11-24 04:58 +0000
  Re: LC53, a respectable random generator? "Rod Pemberton" <dont_use_email@xnohavenotit.cnm> - 2013-11-24 04:57 -0500
    Re: LC53, a respectable random generator? albert@spenarnc.xs4all.nl (Albert van der Horst) - 2013-11-24 14:17 +0000
      Re: LC53, a respectable random generator? mhx@iae.nl - 2013-11-24 08:12 -0800
        Re: LC53, a respectable random generator? albert@spenarnc.xs4all.nl (Albert van der Horst) - 2013-11-24 16:46 +0000
        Re: LC53, a respectable random generator? Bernd Paysan <bernd.paysan@gmx.de> - 2013-11-24 23:53 +0100
          Re: LC53, a respectable random generator? mhx@iae.nl - 2013-11-24 15:41 -0800
            Re: LC53, a respectable random generator? hughaguilar96@yahoo.com - 2013-11-24 17:57 -0800
            Re: LC53, a respectable random generator? albert@spenarnc.xs4all.nl (Albert van der Horst) - 2013-11-25 19:32 +0000
              Re: LC53, a respectable random generator? mhx@iae.nl - 2013-11-25 14:22 -0800
              Re: LC53, a respectable random generator? Bernd Paysan <bernd.paysan@gmx.de> - 2013-11-26 00:20 +0100
                Re: LC53, a respectable random generator? albert@spenarnc.xs4all.nl (Albert van der Horst) - 2013-11-26 03:29 +0000
                Re: LC53, a respectable random generator? thomas.bartscher@gmail.com - 2013-11-25 23:08 -0800
                Re: LC53, a respectable random generator? hughaguilar96@yahoo.com - 2013-11-26 05:06 -0800
                Re: LC53, a respectable random generator? albert@spenarnc.xs4all.nl (Albert van der Horst) - 2013-11-26 14:03 +0000
                Re: LC53, a respectable random generator? Bernd Paysan <bernd.paysan@gmx.de> - 2013-11-26 21:59 +0100
                Re: LC53, a respectable random generator? thomas.bartscher@gmail.com - 2013-11-28 01:32 -0800
                Re: LC53, a respectable random generator? hughaguilar96@yahoo.com - 2013-11-25 19:43 -0800
              Re: LC53, a respectable random generator? hughaguilar96@yahoo.com - 2013-11-25 19:31 -0800
              Re: LC53, a respectable random generator? "Elizabeth D. Rather" <erather@forth.com> - 2013-11-25 19:24 -1000
                Re: LC53, a respectable random generator? hughaguilar96@yahoo.com - 2013-11-26 05:17 -0800
                Re: LC53, a respectable random generator? albert@spenarnc.xs4all.nl (Albert van der Horst) - 2013-11-26 14:21 +0000
                Re: LC53, a respectable random generator? hughaguilar96@yahoo.com - 2013-11-28 18:49 -0800
            Re: LC53, a respectable random generator? mhx@iae.nl - 2013-11-25 13:52 -0800
          Re: LC53, a respectable random generator? hughaguilar96@yahoo.com - 2013-11-24 18:03 -0800
          Re: LC53, a respectable random generator? Matthias Koch <matthias.koch@hot.uni-hannover.de> - 2013-11-25 13:41 +0100
            Re: LC53, a respectable random generator? mhx@iae.nl - 2013-11-25 10:23 -0800
              Re: LC53, a respectable random generator? Howerd <howerdo@yahoo.co.uk> - 2013-11-25 13:43 -0800
                Re: LC53, a respectable random generator? mhx@iae.nl - 2013-11-25 15:16 -0800
                Re: LC53, a respectable random generator? Howerd <howerdo@yahoo.co.uk> - 2013-11-26 13:38 -0800
                Re: LC53, a respectable random generator? hughaguilar96@yahoo.com - 2013-11-26 20:42 -0800
                Re: LC53, a respectable random generator? albert@spenarnc.xs4all.nl (Albert van der Horst) - 2013-11-27 11:46 +0000
                Re: LC53, a respectable random generator? hughaguilar96@yahoo.com - 2013-11-27 18:35 -0800
                Re: LC53, a respectable random generator? hughaguilar96@yahoo.com - 2013-11-26 21:41 -0800
                Re: LC53, a respectable random generator? Andrew Haley <andrew29@littlepinkcloud.invalid> - 2013-11-27 03:21 -0600
                Re: LC53, a respectable random generator? albert@spenarnc.xs4all.nl (Albert van der Horst) - 2013-11-27 15:37 +0000
                Re: LC53, a respectable random generator? Bernd Paysan <bernd.paysan@gmx.de> - 2013-11-27 23:01 +0100
                Re: LC53, a respectable random generator? albert@spenarnc.xs4all.nl (Albert van der Horst) - 2013-11-27 23:39 +0000
                Re: LC53, a respectable random generator? Andrew Haley <andrew29@littlepinkcloud.invalid> - 2013-11-28 05:41 -0600
                Re: LC53, a respectable random generator? albert@spenarnc.xs4all.nl (Albert van der Horst) - 2013-11-28 13:47 +0000
                Re: LC53, a respectable random generator? Andrew Haley <andrew29@littlepinkcloud.invalid> - 2013-11-28 09:10 -0600
                Re: LC53, a respectable random generator? Bernd Paysan <bernd.paysan@gmx.de> - 2013-11-28 16:22 +0100
                Re: LC53, a respectable random generator? Andrew Haley <andrew29@littlepinkcloud.invalid> - 2013-11-28 09:34 -0600
                Re: LC53, a respectable random generator? hughaguilar96@yahoo.com - 2013-11-28 18:39 -0800
                Re: LC53, a respectable random generator? albert@spenarnc.xs4all.nl (Albert van der Horst) - 2013-11-27 16:44 +0000
            Re: LC53, a respectable random generator? Bernd Paysan <bernd.paysan@gmx.de> - 2013-11-25 19:51 +0100
      Re: LC53, a respectable random generator? hughaguilar96@yahoo.com - 2013-11-24 11:13 -0800
        Re: LC53, a respectable random generator? Hans Bezemer <the.beez.speaks@gmail.com> - 2013-11-25 09:52 +0100
  Re: LC53, a respectable random generator? hughaguilar96@yahoo.com - 2013-11-24 13:07 -0800
    Re: LC53, a respectable random generator? albert@spenarnc.xs4all.nl (Albert van der Horst) - 2013-11-25 02:18 +0000
      Re: LC53, a respectable random generator? hughaguilar96@yahoo.com - 2013-11-24 19:36 -0800
  Re: LC53, a respectable random generator? "Ed" <invalid@invalid.com> - 2013-11-26 12:57 +1100
    Re: LC53, a respectable random generator? hughaguilar96@yahoo.com - 2013-11-26 21:25 -0800
    Re: LC53, a respectable random generator? albert@spenarnc.xs4all.nl (Albert van der Horst) - 2013-11-27 15:48 +0000
  Re: LC53, a respectable random generator? Mark Wills <markrobertwills@yahoo.co.uk> - 2013-11-27 01:10 -0800
    Re: LC53, a respectable random generator? Andrew Haley <andrew29@littlepinkcloud.invalid> - 2013-11-27 03:29 -0600
      Re: LC53, a respectable random generator? hughaguilar96@yahoo.com - 2013-11-27 19:49 -0800
        Re: LC53, a respectable random generator? Bernd Paysan <bernd.paysan@gmx.de> - 2013-11-28 15:57 +0100
          Re: LC53, a respectable random generator? hughaguilar96@yahoo.com - 2013-11-28 18:14 -0800

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