Re: Text modes show military times. How do I change it to 12 hours



On 28/11/11 19:42, John Hasler wrote:
unruh writes:
You really should think while you read. 12:30 is after noon (noon
being 12:00) Post Meridian. But it is labeled as AM. because it is 30
minutes after 12:00 noon which by convention is 12:00 AM.

12:00 noon is neither AM nor PM. It is the meridian: what AM is ante

12:00 noon refers to the minute that starts exactly at midday, and runs up to but not including the point of time 1 minute after midday. This minute is all /after/ midday, thus it is unambiguously called 12:00 PM.

and PM is post. PM is straightforward: it is hours since noon. Thus
12:30PM is silly but unambiguous: 12.5 hours after noon or 1/2 hour
after midnight. AM cannot be hours before noon, though, or midnight
would be followed one hour later by 11:00AM. Thus it must be hours into
the twelve-hour ante meridian period so that 1:00AM is indeed the weeest
hour of the morning. 12:30AM then is 12.5 hours into the ante meridian
period or 1/2 hour after noon: again silly but unambiguous.


Silly, and wrong. 12:30 am is shortly after midnight.

But the very fact that people can get this so badly wrong shows why the 24 clock is a better system.

<http://en.wikipedia.org/wiki/12_hour_clock>


Perhaps we should go back to doing what the astronomers still do and
increment the day number at noon.

Better yet, Let's use a numbered stream of TAI seconds since the big
bang and be rid of all the geocentric nonsense.

.



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