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Re: Measuring time

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Dr J R Stockton wrote:

> On Thursday, October 19, 2017 at 9:58:26 PM UTC+1, Thomas 'PointedEars'
> Lahn wrote:

Attribution line, not attribution novel.

>  > Apropos, it had just occurred to me (when reading that the first time
>  > the
>> on-board cesium clocks of the GPS NTS-2 satellite were tested was on “day
>> 190, 1977”) that you can obtain the date for day N of year Y using
>> 
>>   new Date(Y, 0, N)
> 
> The likelihood of that is fairly obvious on considering
> 
> ECMA-262-1, Jun 1997, 15.9.1.12 MakeDay(year, month, date), list entry 1
> or
> ECMA-262-7, Jun 2016, 20.3.1.13 MakeDay (year, month, date), list entry 1
> or I suppose the corresponding parts of all other ECMA-262.

(You are preaching to the choir.)  I thought that to be obvious.
 
> IIRC, new Date(Y, 0, N) fails for years 0 to 99;

It fails for those years in V8 JavaScript 5.7.492.63 in Chromium 
57.0.2987.98 on Debian/Devuan GNU+Linux in that they are considered
the years 1900 to 1999 CE instead (also see below):

| -> new Date(99, 0, 1)
| <- Fri Jan 01 1999 00:00:00 GMT+0100 (CET)

However, while “new Date(0, 0, 1)” cannot be used to produce January 1,
1 BCE according to the Proleptic Gregorian calendar, it is apparently 
possible to do that in another way:

| -> var d = new Date(0, 0, 1); console.log(d); d.setFullYear(0);
|    console.log(d);
| Mon Jan 01 1900 00:00:00 GMT+0100 (CET)
| Sat Jan 01    0 00:00:00 GMT+0100 (CET)

<https://en.wikipedia.org/wiki/1_BC> says that it was a Saturday indeed.

> and MD is wrong for most of Year 0.

That is a matter of interpretation or, if understood as specified, it does 
not appear to be the case in that implementation (see above).  According to 
Wikipedia, 1999-01-01 CE *was* a Monday indeed:

<https://en.wikipedia.org/wiki/January_1900#January_1.2C_1900_.28Monday.29>

Please clarify, or cite evidence to support, your assumption.

-- 
PointedEars
FAQ: <http://PointedEars.de/faq> | <http://PointedEars.de/es-matrix>
<https://github.com/PointedEars> | <http://PointedEars.de/wsvn/>
Twitter: @PointedEars2 | Please do not cc me./Bitte keine Kopien per E-Mail.

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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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