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Re: Random numbers

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emf wrote:

> The discussion was quite interesting and it gave me leads to pursue. But 
> here is a more specific question: would the following function provide 
> *more* random results than the Math.random()?
> 
> // returns a random number from 1 to top
> function random(top) {
>      var now = new Date();
>      var hh = now.getHouera();
>      var mm = now.getMinutes();
>      var ss = now.getSeconds();
>      var ms = now.getMilliseconds();
>      var tim = (hh * 1440000) + (mm * 60000) + (ss * 1000) +  ms;
>      var rndm = (tim % top) + 1;
>      return rndm;
> }

Given that Math.random is implementation dependent [1] it's possible for one to create a better one, but yours is broken.

random(1) => 1
random(0) => NaN

If you wan't something reasonable, I'd suggest this as an exercise:

<https://en.wikipedia.org/wiki/Linear_congruential_generator>

[1] <https://tc39.github.io/ecma262/#sec-math.random>

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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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