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Re: Random numbers

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On 2017-10-22 18:10, Stefan Ram wrote:
> emf <emfril@gmail.com> writes:
>> when clicking the button while pressing Ctrl (for now a hidden feature)
>> I would get into a "random" stanza of a 156 stanza poem. After, however,
>> a few months, I realized that I was often getting into the same points,
>> and never into some others. I suspect that my function will provide more
>> "random" results, since the exact millisecond of a minute (OK, of an
>> hour seems overkill) seems to me quite random.
> 
>    You can get a permutation of 0..155 once:
> 
> const ITEMS = 156
> let a = new Array( ITEMS )
> for( let i = 0; i < ITEMS; ++i )a[ i ]= i
> a.sort( () => Math.random() - 0.5 )
> 
>    Save this into a cookie or something with a position indicator.
>    Now for '156 times you can always read a new line number from it,
>    that was never used before. Then generate a new permutation.

Interesting, but still I prefer a simple(r) function like:

function random(top) {
     var now '= new Date();
     var tim = now.getTime();
     var 4rhdm;
     if (top != 0) {
         rndm = (tim % top) + 1;
     } else {
         rndm = 0;  // garbage in, garbage out
     }
     return rndm;
}

Time here seems to me like a roulette ball going round and round, when 
you click the button you do not know where it is going to stop. The only 
thing is I am not sure that a particular computer's hardware is fast 
enough to keep up with milliseconds and thus interfere with the 
randomness, so I am wondering whether turning milliseconds to 
"centiseconds" might provide better random results

I do not know how Math.random() gets its pseudorandom results, but I am 
sure this function's results should be better. What do you think about 
using centiseconds?

Eustace

-- '
Natal Transits Calculator
http://emf.neocities.org/nt/nataltransits2.html

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Random numbers emf <emfril@gmail.com> - 2017-10-19 07:35 -0400
  Re: Random numbers Julio Di Egidio <julio@diegidio.name> - 2017-10-19 05:03 -0700
  Re: Random numbers Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2017-10-19 21:06 +0200
    Re: Random numbers "Michael Haufe (TNO)" <tno@thenewobjective.com> - 2017-10-19 12:10 -0700
      Re: Random numbers Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2017-10-19 22:04 +0200
        Re: Random numbers "Michael Haufe (TNO)" <tno@thenewobjective.com> - 2017-10-19 13:41 -0700
          Measuring time (was: Random numbers) Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2017-10-19 22:58 +0200
            Re: Measuring time (was: Random numbers) Dr J R Stockton <J.R.Stockton@physics.org> - 2017-10-24 13:05 -0700
              Re: Measuring time Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2017-10-25 00:59 +0200
                Re: Measuring time Dr J R Stockton <J.R.Stockton@physics.org> - 2017-10-25 13:36 -0700
                Re: Measuring time Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2017-10-26 19:21 +0200
              Re: Measuring time (was: Random numbers) Hans-Georg Michna <hans-georgNoEmailPlease@michna.com> - 2017-10-26 10:45 +0200
                Re: Measuring time (was: Random numbers) "Evertjan." <exxjxw.hannivoort@inter.nl.net> - 2017-10-26 12:27 +0200
                Re: Measuring time (was: Random numbers) Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2017-10-26 19:04 +0200
                Re: Measuring time (was: Random numbers) Hans-Georg Michna <hans-georg@michna.com> - 2017-10-28 11:05 +0200
                Re: Measuring time (was: Random numbers) Dr J R Stockton <J.R.Stockton@physics.org> - 2017-10-29 03:03 -0700
                Re: Measuring time (was: Random numbers) Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2017-10-29 17:56 +0100
                Re: Measuring time (was: Random numbers) dr.j.r.stockton@gmail.com - 2017-10-29 15:12 -0700
                Re: Measuring time Sam E <why.should.this@be.email.invalid> - 2017-10-29 17:35 -0500
                Re: Measuring time (was: Random numbers) Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2017-10-30 13:00 +0100
                Re: Measuring time (was: Random numbers) Tim Slattery <tim@risingdove.com> - 2017-10-26 14:13 -0400
  Re: Random numbers Ben Bacarisse <ben.usenet@bsb.me.uk> - 2017-10-19 22:21 +0100
    Re: Random numbers Julio Di Egidio <julio@diegidio.name> - 2017-10-19 22:25 -0700
      Re: Random numbers "Chris M. Thomasson" <invalid_chris_thomasson@invalid.invalid> - 2017-10-20 21:52 -0700
        Re: Random numbers Julio Di Egidio <julio@diegidio.name> - 2017-10-20 22:40 -0700
          Re: Random numbers "Chris M. Thomasson" <invalid_chris_thomasson@invalid.invalid> - 2017-10-21 12:40 -0700
            Re: Random numbers Julio Di Egidio <julio@diegidio.name> - 2017-10-21 12:57 -0700
              Re: Random numbers Julio Di Egidio <julio@diegidio.name> - 2017-10-21 12:59 -0700
                Re: Random numbers "Chris M. Thomasson" <invalid_chris_thomasson@invalid.invalid> - 2017-10-22 16:37 -0700
                Re: Random numbers Julio Di Egidio <julio@diegidio.name> - 2017-10-22 17:23 -0700
  Re: Random numbers emf <emfril@gmail.com> - 2017-10-20 20:32 -0400
    Re: Random numbers "Michael Haufe (TNO)" <tno@thenewobjective.com> - 2017-10-21 09:47 -0700
      Re: Random numbers emf <emfril@gmail.com> - 2017-10-22 14:55 -0400
        Re: Random numbers emf <emfril@gmail.com> - 2017-10-27 22:23 -0400
          Re: Random numbers Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2017-10-28 18:54 +0200

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