 Check out the bookstore at IRBS.com |
|
|
|
|||||
|
||||||
Subject: Re: Noon (was Sexagesimal)
From: Dan Allen (danallen46@XXX.XXX)
Date: Tue Feb 19 2002 - 14:22:29 EST
These are all just agreed upon conventions. Some US government website
I was at recently said that 12:00:00 AM (midnight) belongs to the day
just starting, so a day ends at 11:59:59 PM, the second before midnight.
Since the PM becomes AM at 12:00:00 AM (0000), then the corresponding
flip from AM to PM occurs at 12:00:00 PM (1200). So Noon is PM.
Actually, the instant of noon of course is neither AM or PM because of
the definitions: Ante Meridian and Post Meridian, and Noon is Meridian
itself.
Thinking about this reminds me of the "off-by-one" programming
errors that cause us to always stop and think carefully when running
through an array with an index...
Dan
-----Original Message-----
From: Navigation Mailing List
[mailto:NAVIGATION-L@XXX.XXX]On Behalf Of Lu Abel
Sent: Tuesday, February 19, 2002 10:13 AM
To: NAVIGATION-L@XXX.XXX
Subject: Re: Sexagesimal (was Newbie - Variation..)
Hey, while we're at it, why don't we debate 0000 vs 2400?
And, for a more esoteric question, does midnight belong to the earlier or
later of the days it separates?
But, wait, there's more! Is noon 12AM or 12PM? What about midnight?
All but the first are very important to me in programming my VCR when I
want to record a program starting at midnight. Have not yet been able to
fathom the mind of the Japanese VCR designer, so I just program the damn
thing to start at 12:01 AM, on that there is at least universal agreement
as to time and day. ;-)
Lu Abel
At 11:08 AM 2/17/2002 -0800, you wrote:
>OK, Brian and Trevor, looks like we're going to have to bring in the Olympic
>figure skating judges to sort this one out. I'm learning so much from all
>you guys, and the drama and good-natured(?) ribbing certainly add a little
>spice to the experience. I love this list. Jim (snowbound in the North
>Cascades) Laskey
>
>|
>|
>|Brian Whatcott wrote:
>|
>|> Actually, it is not quite correct to suppose one can strictly refer to
>|> 0 degrees AND 360 degrees.
>|
>|Of course. But we can strictly refer to both zero degrees and
>|359.99999.....
>|
>|Truncating at either 1 or 359 degrees would loose one 360th of the
>|circle. A small and academic point, perhaps, but one that even a
>|non-mathematical biologist can understand.
>|
>|
>|Trevor Kenchington
>|
>|
>|--
>|Trevor J. Kenchington PhD Gadus@XXX.XXX
>|Gadus Associates, Office(902) 889-9250
>|R.R.#1, Musquodoboit Harbour, Fax (902) 889-9251
>|Nova Scotia B0J 2L0, CANADA Home (902) 889-3555
>|
>| Science Serving the Fisheries
>| http://home.istar.ca/~gadus
|