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Re: Fair, truly random random number generator

From "Osmium" <r124c4u102@comcast.net>
Newsgroups comp.lang.c
Subject Re: Fair, truly random random number generator
Date 2016-10-30 11:07 -0600
Message-ID <e7mnm9F28igU1@mid.individual.net> (permalink)
References <nuvgeh$2fm$1@dont-email.me> <37481339-6cc2-4bef-b550-4c868b3159d2@googlegroups.com> <nv2ea3$99s$2@dont-email.me> <nv566b$se1$1@dont-email.me>

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"David Brown" wrote:

> On 29/10/16 17:13, Mr. Man-wai Chang wrote:
>> On 28/10/2016 10:14 PM, Rick C. Hodgin wrote:
>>> Several CPU manufacturers have introduced hardware which generates truly
>>> random sequences based on internal circuits which monitor heat radiation
>>> ...
>>> Others CPU manufacturers have done similarly.
>>
>> Intel CPU?
>>
>>> If you really want a true random number generator locally, you can buy
>>> add-on boards which provide that functionality through an API call:
>>> http://www.idquantique.com/random-number-generation/quantis-random-number-generator/
>>>
>>
>> NO plan to invest in hardware solution.
>>
>> I just want to play my MP3 songs in shuffle mode. I noticed that most
>> shuffling algorithms are not random enough, as I could hear a pattern
>> being repeated. :)
>>
>
> It depends on what you mean by "a pattern being repeated".  Suppose you 
> have a dozen songs, shuffled randomly, which you listen to.  Then you 
> shuffle them again, and listen again.  Then you notice that a particular 
> pair of songs follow each other, just as they did in the previous set. A 
> pattern!
>
> In fact, even if the shuffling was perfectly random, you are going to get 
> such pairs.  I haven't bothered doing the maths, but my guess is the 
> chances are millions to one against you /not/ having such pairs with a 
> dozen songs in your mix.  If you have a few dozen songs on your list, you 
> are going to get runs of three or more matches on a regular basis.
>
> So if a shuffle algorithm is /not/ producing such combinations, it is a 
> strong sign that it is not actually very random.

If I were to write a shuffle program such as the one being discussed, I 
would take pains to make sure it *was not* random. If the average citizen 
hears song A followed by song A, he is going to be annoyed. Might as well 
fix it now rather than a post-release "fix".

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Fair, truly random random number generator "Mr. Man-wai Chang" <toylet.toylet@gmail.com> - 2016-10-28 20:31 +0800
  Re: Fair, truly random random number generator "Osmium" <r124c4u102@comcast.net> - 2016-10-28 07:48 -0500
    Re: Fair, truly random random number generator "Mr. Man-wai Chang" <toylet.toylet@gmail.com> - 2016-10-28 21:07 +0800
      Re: Fair, truly random random number generator Richard Heathfield <rjh@cpax.org.uk> - 2016-10-28 14:21 +0100
        Re: Fair, truly random random number generator Gareth Owen <gwowen@gmail.com> - 2016-10-28 16:22 +0100
          Re: Fair, truly random random number generator Richard Heathfield <rjh@cpax.org.uk> - 2016-10-28 16:30 +0100
            Re: Fair, truly random random number generator Gareth Owen <gwowen@gmail.com> - 2016-10-28 16:32 +0100
        Re: Fair, truly random random number generator "Mr. Man-wai Chang" <toylet.toylet@gmail.com> - 2016-10-29 23:11 +0800
          Re: Fair, truly random random number generator Richard Heathfield <rjh@cpax.org.uk> - 2016-10-31 11:17 +0000
            Re: Fair, truly random random number generator "Mr. Man-wai Chang" <toylet.toylet@gmail.com> - 2016-10-31 20:14 +0800
              Re: Fair, truly random random number generator Melzzzzz <Melzzzzz@zzzzz.com> - 2016-10-31 12:32 +0000
                Re: Fair, truly random random number generator Richard Heathfield <rjh@cpax.org.uk> - 2016-10-31 12:48 +0000
                Re: Fair, truly random random number generator "Mr. Man-wai Chang" <toylet.toylet@gmail.com> - 2016-11-01 15:30 +0800
              Re: Fair, truly random random number generator Richard Heathfield <rjh@cpax.org.uk> - 2016-10-31 12:47 +0000
      Re: Fair, truly random random number generator "Osmium" <r124c4u102@comcast.net> - 2016-10-28 09:32 -0500
  Re: Fair, truly random random number generator "Rick C. Hodgin" <rick.c.hodgin@gmail.com> - 2016-10-28 07:14 -0700
    Re: Fair, truly random random number generator "Chris M. Thomasson" <invalid@invalid.invalid> - 2016-10-28 18:07 -0700
      Re: Fair, truly random random number generator "Chris M. Thomasson" <invalid@invalid.invalid> - 2016-11-01 17:45 -0700
        Re: Fair, truly random random number generator "Rick C. Hodgin" <rick.c.hodgin@gmail.com> - 2016-11-01 18:57 -0700
          Re: Fair, truly random random number generator David Brown <david.brown@hesbynett.no> - 2016-11-02 10:06 +0100
            Re: Fair, truly random random number generator "Osmium" <r124c4u102@comcast.net> - 2016-11-02 04:46 -0600
            Re: Fair, truly random random number generator "Rick C. Hodgin" <rick.c.hodgin@gmail.com> - 2016-11-02 05:06 -0700
              Re: Fair, truly random random number generator David Brown <david.brown@hesbynett.no> - 2016-11-02 13:43 +0100
                Re: Fair, truly random random number generator "Rick C. Hodgin" <rick.c.hodgin@gmail.com> - 2016-11-02 06:02 -0700
                Re: Fair, truly random random number generator David Brown <david.brown@hesbynett.no> - 2016-11-02 16:08 +0100
                Re: Fair, truly random random number generator "Rick C. Hodgin" <rick.c.hodgin@gmail.com> - 2016-11-02 08:21 -0700
              Re: Fair, truly random random number generator Mark Storkamp <mstorkamp@yahoo.com> - 2016-11-02 08:20 -0500
          Re: Fair, truly random random number generator "Chris M. Thomasson" <invalid@invalid.invalid> - 2016-11-03 17:56 -0700
            Re: Fair, truly random random number generator Keith Thompson <kst-u@mib.org> - 2016-11-03 18:16 -0700
              Re: Fair, truly random random number generator "Chris M. Thomasson" <invalid@invalid.invalid> - 2016-11-03 18:48 -0700
              Re: Fair, truly random random number generator supercat@casperkitty.com - 2016-11-04 09:17 -0700
              Re: Fair, truly random random number generator raltbos@xs4all.nl (Richard Bos) - 2016-11-04 17:59 +0000
                Re: Fair, truly random random number generator Keith Thompson <kst-u@mib.org> - 2016-11-04 11:55 -0700
                Re: Fair, truly random random number generator "Chris M. Thomasson" <invalid@invalid.invalid> - 2016-11-04 12:43 -0700
                Re: Fair, truly random random number generator "Chris M. Thomasson" <invalid@invalid.invalid> - 2016-11-04 12:40 -0700
            Re: Fair, truly random random number generator "Rick C. Hodgin" <rick.c.hodgin@gmail.com> - 2016-11-04 12:49 -0700
              Re: Fair, truly random random number generator "Chris M. Thomasson" <invalid@invalid.invalid> - 2016-11-04 13:23 -0700
                Re: Fair, truly random random number generator "Rick C. Hodgin" <rick.c.hodgin@gmail.com> - 2016-11-04 13:32 -0700
                Re: Fair, truly random random number generator ImperiusDamian <damianblack.wolf@gmail.com> - 2016-11-05 18:48 -0400
                Re: Fair, truly random random number generator "Rick C. Hodgin" <rick.c.hodgin@gmail.com> - 2016-11-05 16:03 -0700
                Re: Fair, truly random random number generator "Chris M. Thomasson" <invalid@invalid.invalid> - 2016-11-05 16:50 -0700
                Re: Fair, truly random random number generator ImperiusDamian <damianblack.wolf@gmail.com> - 2016-11-05 19:52 -0400
                Re: Fair, truly random random number generator "Rick C. Hodgin" <rick.c.hodgin@gmail.com> - 2016-11-05 17:06 -0700
    Re: Fair, truly random random number generator "Mr. Man-wai Chang" <toylet.toylet@gmail.com> - 2016-10-29 23:13 +0800
      Re: Fair, truly random random number generator Lew Pitcher <lew.pitcher@digitalfreehold.ca> - 2016-10-29 12:12 -0400
        Re: Fair, truly random random number generator "Mr. Man-wai Chang" <toylet.toylet@gmail.com> - 2016-10-30 00:22 +0800
        Re: Fair, truly random random number generator Lew Pitcher <lew.pitcher@digitalfreehold.ca> - 2016-10-29 12:26 -0400
        Re: Fair, truly random random number generator supercat@casperkitty.com - 2016-10-29 09:44 -0700
          Re: Fair, truly random random number generator Tim Rentsch <txr@alumni.caltech.edu> - 2016-11-01 08:13 -0700
            Re: Fair, truly random random number generator supercat@casperkitty.com - 2016-11-01 08:31 -0700
              Re: Fair, truly random random number generator Tim Rentsch <txr@alumni.caltech.edu> - 2016-11-02 12:58 -0700
      Re: Fair, truly random random number generator "James R. Kuyper" <jameskuyper@verizon.net> - 2016-10-29 12:37 -0400
      Re: Fair, truly random random number generator Keith Thompson <kst-u@mib.org> - 2016-10-29 11:57 -0700
      Re: Fair, truly random random number generator David Brown <david.brown@hesbynett.no> - 2016-10-30 17:13 +0100
        Re: Fair, truly random random number generator "Osmium" <r124c4u102@comcast.net> - 2016-10-30 11:07 -0600
          Re: Fair, truly random random number generator supercat@casperkitty.com - 2016-10-30 12:20 -0700
      Re: Fair, truly random random number generator Richard Heathfield <rjh@cpax.org.uk> - 2016-10-31 11:18 +0000
      Re: Fair, truly random random number generator Ed Prochak <edprochak@gmail.com> - 2016-11-03 10:39 -0700
        Re: Fair, truly random random number generator "Rick C. Hodgin" <rick.c.hodgin@gmail.com> - 2016-11-03 11:13 -0700
          [OT] gigawatts = gigaseconds correlation? "Mr. Man-wai Chang" <toylet.toylet@gmail.com> - 2016-11-04 02:36 +0800
            Re: [OT] gigawatts = gigaseconds correlation? "Rick C. Hodgin" <rick.c.hodgin@gmail.com> - 2016-11-03 12:07 -0700
              Re: [OT] gigawatts = gigaseconds correlation? "Mr. Man-wai Chang" <toylet.toylet@gmail.com> - 2016-11-04 12:02 +0800
          Re: Fair, truly random random number generator gazelle@shell.xmission.com (Kenny McCormack) - 2016-11-03 19:56 +0000
          Re: Fair, truly random random number generator "Rick C. Hodgin" <rick.c.hodgin@gmail.com> - 2016-11-03 16:21 -0700
  Re: Fair, truly random random number generator luser droog <luser.droog@gmail.com> - 2016-10-29 14:49 -0700
    Re: Fair, truly random random number generator jameskuyper@verizon.net - 2016-10-29 15:29 -0700
  Re: Fair, truly random random number generator Quadibloc <jsavard@ecn.ab.ca> - 2016-10-29 19:09 -0700
  Thank you all for the replies! "Mr. Man-wai Chang" <toylet.toylet@gmail.com> - 2016-10-31 18:42 +0800

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