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Re: Noon (was Sexagesimal)
From: Dan Allen
Date: 2002 Feb 19, 11:22 -0800
From: Dan Allen
Date: 2002 Feb 19, 11:22 -0800
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@LISTSERV.WEBKAHUNA.COM]On Behalf Of Lu Abel Sent: Tuesday, February 19, 2002 10:13 AM To: NAVIGATION-L@LISTSERV.WEBKAHUNA.COM 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@iStar.ca >|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