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Re: Will Math.random return 0.0?

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On Sat, 16 Jul 2016 16:12:30 -0400, Eric Sosman wrote:

> On 7/16/2016 3:39 PM, Martin Gregorie wrote:
>> [...]
>> Meanwhile, your original code had been running for a while before I
>> developed and played with my extended version and has currently used
>> 100.5 minutes of MPU time, which is close to 1 hour 40 since its using
>> between 99 and 100% of the available CPU time from one of the two
>> cores. This is running on a laptop powered by a 1.6 GHz Core Duo with
>> 3GB of RAM and running Fedora 23 Linux.
>>
>> My billion sample run took 132 seconds to run, or 7.6 million samples
>> were generated and analysed per second.
>>
>> I'll leave your code running to see if it stops any time thus evening.
> 
>      Back of the envelope: 2^53 possible numerators (maybe), one of
> which is all zero.  7.6 million ~= 2^23 samples per second.  Time to
> cycle through all numerators ~= 2^(53-23) ~= 1E9 seconds, which is just
> about thirty-four years.  Maybe only half that if we leave out the
> analysis, so you should have a definite conclusion by 2033 or so.
> And maybe you'll only need to get half way through the full cycle to hit
> pay dirt, so I'll pencil you in for, um, 2025.

Fair enough. Since its 100% use of one core isn't interfering with 
anything else this laptop is doing or eating the battery faster than the 
charger is filling it, I'll leave it running to see if I get lucky.


-- 
martin@   | Martin Gregorie
gregorie. | Essex, UK
org       |

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Re: Will Math.random return 0.0? Martin Gregorie <martin@address-in-sig.invalid> - 2016-07-16 19:39 +0000
  Re: Will Math.random return 0.0? Eric Sosman <esosman@comcast-dot-net.invalid> - 2016-07-16 16:12 -0400
    Re: Will Math.random return 0.0? Martin Gregorie <martin@address-in-sig.invalid> - 2016-07-16 20:32 +0000
      Re: Will Math.random return 0.0? Martin Gregorie <martin@address-in-sig.invalid> - 2016-07-17 08:00 +0000
    Re: Will Math.random return 0.0? Arne Vajhøj <arne@vajhoej.dk> - 2016-07-16 16:47 -0400
    Re: Will Math.random return 0.0? Marcel Mueller <news.5.maazl@spamgourmet.org> - 2016-07-17 01:03 +0200

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