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Re: Random 64 bit number in stdc

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"Phil Carmody" wrote:

> "osmium" <r124c4u102@comcast.net> writes:
>> "Öö Tiib" wrote:
>> > It is often (I would agree with Phil that almost idiomatically) seeded
>> > with wrong things like 'time(0)' that Wikipedia's article mentions
>> > several times: "The Mersenne Twister is sensitive to poor 
>> > initialization
>> > and can take a long time to recover from a zero-excess initial state."
>>
>> Life is much too short to read this thread.  But do you guys realize that 
>> _A
>> Million Random Digits_ is available for a free download?  That would seem 
>> to
>> provide a decent seed.
>>
>> http://www.rand.org/pubs/monograph_reports/MR1418.html
>
> ARGH!!! I hope you're not trolling, as you've got a bite.
>
> Firstly, the method they used to generate those numbers is flawed.
> I think it's at least 50 bits short of the maximum possible entropy
> in such a stream. (See comp.compression from about 5-10 years ago.)
>
> Secondly, any randomly-generated stream of numbers, once written down,
> is no longer random. It's entirely predictable, just like the digits
> of pi.
>
> It's best to get out of the mindset of thinking about "random numbers"
> but to instead think about "random sources/generators".
>
> Is 9 a random number? You don't know whether it is or it isn't, as
> it's not a property of the number. If I told you how I generated it,
> then you would possibly be able to judge better whether it satisfies
> your desire for randomness or not.

Your thing about writing numbers down is branching into some area, 
philosophy or something, that I don't want to go. I am only interested in 
writing computer programs that work and do what someone wants done.  I will 
leave it to you to think about Schrödinger's cat and the other *really* 
important stuff.

I am not going to be shocked at a modest compression here or there.  I don't 
know the method used to create these digits but they have been around long 
enough - mid 60's?- to have been thoroughly critiqued.   I looked for 
critiques but instead I find _reviews_, all of the ones I looked at were by 
"civilians" trying to be funny.  The notion of random numbers makes an awful 
lot of people giggle.  If you have a link to factual reviews, please post 
them.  I do not consider "The method used was flawed..." to be a critique. 
I think that is called "bitching".

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Re: Random 64 bit number in stdc Tim Rentsch <txr@alumni.caltech.edu> - 2013-08-20 20:52 -0700
  Re: Random 64 bit number in stdc Phil Carmody <thefatphil_demunged@yahoo.co.uk> - 2013-08-23 11:42 +0300
    Re: Random 64 bit number in stdc James Kuyper <jameskuyper@verizon.net> - 2013-08-23 07:09 -0400
      Re: Random 64 bit number in stdc Phil Carmody <thefatphil_demunged@yahoo.co.uk> - 2013-08-23 17:55 +0300
        Re: Random 64 bit number in stdc James Kuyper <jameskuyper@verizon.net> - 2013-08-23 12:29 -0400
    Re: Random 64 bit number in stdc Keith Thompson <kst-u@mib.org> - 2013-08-23 08:32 -0700
      Re: Random 64 bit number in stdc Öö Tiib <ootiib@hot.ee> - 2013-08-23 09:32 -0700
        Re: Random 64 bit number in stdc glen herrmannsfeldt <gah@ugcs.caltech.edu> - 2013-08-23 17:47 +0000
        Re: Random 64 bit number in stdc Phil Carmody <thefatphil_demunged@yahoo.co.uk> - 2013-08-24 13:24 +0300
          Re: Random 64 bit number in stdc Keith Thompson <kst-u@mib.org> - 2013-08-24 15:27 -0700
        Re: Random 64 bit number in stdc "osmium" <r124c4u102@comcast.net> - 2013-08-25 19:05 -0500
          Re: Random 64 bit number in stdc Keith Thompson <kst-u@mib.org> - 2013-08-25 19:54 -0700
          Re: Random 64 bit number in stdc Phil Carmody <thefatphil_demunged@yahoo.co.uk> - 2013-08-27 17:14 +0300
            [OT] Re: Random 64 bit number in stdc Eric Sosman <esosman@comcast-dot-net.invalid> - 2013-08-27 10:52 -0400
              Re: [OT] Re: Random 64 bit number in stdc Phil Carmody <thefatphil_demunged@yahoo.co.uk> - 2013-08-27 18:43 +0300
                Re: [OT] Re: Random 64 bit number in stdc Eric Sosman <esosman@comcast-dot-net.invalid> - 2013-08-27 15:08 -0400
            Re: Random 64 bit number in stdc "osmium" <r124c4u102@comcast.net> - 2013-08-27 10:59 -0500
              Re: Random 64 bit number in stdc James Kuyper <jameskuyper@verizon.net> - 2013-08-27 12:27 -0400
                Re: Random 64 bit number in stdc "osmium" <r124c4u102@comcast.net> - 2013-08-27 13:27 -0500
                Re: Random 64 bit number in stdc James Kuyper <jameskuyper@verizon.net> - 2013-08-27 15:03 -0400
                Re: Random 64 bit number in stdc "osmium" <r124c4u102@comcast.net> - 2013-08-27 19:02 -0500
                Re: Random 64 bit number in stdc James Kuyper <jameskuyper@verizon.net> - 2013-08-27 22:14 -0400
                OT:Re: Random 64 bit number in stdc "osmium" <r124c4u102@comcast.net> - 2013-08-28 07:36 -0500
                Re: OT:Re: Random 64 bit number in stdc James Kuyper <jameskuyper@verizon.net> - 2013-08-28 11:14 -0400
                Re: OT:Re: Random 64 bit number in stdc "osmium" <r124c4u102@comcast.net> - 2013-08-28 10:59 -0500
                Re: OT:Re: Random 64 bit number in stdc James Kuyper <jameskuyper@verizon.net> - 2013-08-28 12:46 -0400
                Re: OT:Re: Random 64 bit number in stdc Phil Carmody <thefatphil_demunged@yahoo.co.uk> - 2013-08-28 21:13 +0300
                Re: OT:Re: Random 64 bit number in stdc James Kuyper <jameskuyper@verizon.net> - 2013-08-28 20:20 -0400
                Re: OT:Re: Random 64 bit number in stdc Ben Bacarisse <ben.usenet@bsb.me.uk> - 2013-08-28 18:07 +0100
                Re: Random 64 bit number in stdc Phil Carmody <thefatphil_demunged@yahoo.co.uk> - 2013-08-28 21:10 +0300
              Re: Random 64 bit number in stdc Phil Carmody <thefatphil_demunged@yahoo.co.uk> - 2013-08-28 21:08 +0300
            Re: Random 64 bit number in stdc Keith Thompson <kst-u@mib.org> - 2013-08-27 12:21 -0700
            Re: Random 64 bit number in stdc Ben Bacarisse <ben.usenet@bsb.me.uk> - 2013-08-28 04:07 +0100
    Re: Random 64 bit number in stdc Tim Rentsch <txr@alumni.caltech.edu> - 2013-08-24 13:38 -0700
      Re: Random 64 bit number in stdc Phil Carmody <thefatphil_demunged@yahoo.co.uk> - 2013-08-25 12:50 +0300
        Re: Random 64 bit number in stdc Tim Rentsch <txr@alumni.caltech.edu> - 2013-08-26 12:54 -0700
          Re: Random 64 bit number in stdc Chris DH <cdhorz@gmail.com> - 2013-08-26 17:05 -0700
            Re: Random 64 bit number in stdc Phil Carmody <thefatphil_demunged@yahoo.co.uk> - 2013-08-27 17:17 +0300
              Re: Random 64 bit number in stdc Chris DH <cdhorz@gmail.com> - 2013-08-27 08:33 -0700
            Re: Random 64 bit number in stdc Tim Rentsch <txr@alumni.caltech.edu> - 2013-08-27 14:02 -0700
              Re: Random 64 bit number in stdc Chris DH <cdhorz@gmail.com> - 2013-08-27 18:51 -0700
                Re: Random 64 bit number in stdc Tim Rentsch <txr@alumni.caltech.edu> - 2013-08-29 09:34 -0700
                Re: Random 64 bit number in stdc Chris DH <cdhorz@gmail.com> - 2013-08-29 17:06 -0700
                Re: Random 64 bit number in stdc Tim Rentsch <txr@alumni.caltech.edu> - 2013-08-31 16:52 -0700
                Re: Random 64 bit number in stdc Chris DH <cdhorz@gmail.com> - 2013-09-01 13:26 -0700
                Re: Random 64 bit number in stdc Keith Thompson <kst-u@mib.org> - 2013-09-01 14:08 -0700
                Re: Random 64 bit number in stdc Tim Rentsch <txr@alumni.caltech.edu> - 2013-09-02 12:41 -0700

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