Re: Time Pedantry (was Re: [SLUG] Which bank doesn't use Linux servers?)
On Thursday 15 April 2010 13:35:13 Adam Kennedy wrote: > And the next thing you know, > incrementing by a day involves half a CPU second because you need to > run a physical model of the orbit of the moon to work out if you are > at a month boundary. If you're trying to deal with that calendar, even that won't work since it is based on the physical sighting of the crescent after the new moon (if it's overcast at sundown, no new month for you). Even absent that you would have to have a latitude and longitude to figure out if the crescent was visible at sundown at the particular location. I once suggested it might be more cost effective to arrange to paint the moon black so that calendar was no longer able to be used. -- SLUG - Sydney Linux User's Group Mailing List - http://slug.org.au/ Subscription info and FAQs: http://slug.org.au/faq/mailinglists.html
Re: Time Pedantry (was Re: [SLUG] Which bank doesn't use Linux servers?)
Of course, that brings up the issue of WHAT day it is, and the need to cleanly support non-gregorian calendars. And the next thing you know, incrementing by a day involves half a CPU second because you need to run a physical model of the orbit of the moon to work out if you are at a month boundary. Adam K On 1 April 2010 16:11, Peter Hardy wrote: > None of this would be a problem if we'd just switch to decimal time in a > single timezone and call it a day. -- SLUG - Sydney Linux User's Group Mailing List - http://slug.org.au/ Subscription info and FAQs: http://slug.org.au/faq/mailinglists.html
Re: Time Pedantry (was Re: [SLUG] Which bank doesn't use Linux servers?)
On 1 April 2010 17:11, Peter Hardy wrote: > None of this would be a problem if we'd just switch to decimal time in a > single timezone and call it a day. http://en.wikipedia.org/wiki/Swatch_Internet_Time -- SLUG - Sydney Linux User's Group Mailing List - http://slug.org.au/ Subscription info and FAQs: http://slug.org.au/faq/mailinglists.html
Re: Time Pedantry (was Re: [SLUG] Which bank doesn't use Linux servers?)
On 1 April 2010 16:56, Daniel Pittman wrote: > Nick Andrew writes: >> On Thu, Apr 01, 2010 at 03:39:00PM +1100, Daniel Pittman wrote: >> >>> If it was my call, I would probably do the same thing. Way too many >>> developers get simple things like "this day has no 2:30AM" or "this day has >>> two 2:00AMs" wrong. >> >> That's why Daylight Savings is fundamentally evil. Too much time data is >> stored in non-canonical formats. > > ...but the real question is if we love or hate the GMT/UTC difference, and > 23:59:61? *cough* :60 *cough* > > Daniel > > Also, do we hate the earthquake that changed the length of the day for messing > with our time-keeping? > http://www.sciencedaily.com/releases/2010/03/100302084522.htm Yes. > (And, finally, for anyone who really wants to despair at the whole thing, > I give you "The Long, Painful History of Time", which is the best write-up > I know of about the engineering difficulties of the topic: > http://naggum.no/lugm-time.html > ) I for one am glad such pages exist. I wish the inventors of time_t had read it. -- SLUG - Sydney Linux User's Group Mailing List - http://slug.org.au/ Subscription info and FAQs: http://slug.org.au/faq/mailinglists.html
Re: Time Pedantry (was Re: [SLUG] Which bank doesn't use Linux servers?)
On Thu, 2010-04-01 at 16:56 +1100, Daniel Pittman wrote: > ...but the real question is if we love or hate the GMT/UTC difference, and > 23:59:61? > > Daniel > > Also, do we hate the earthquake that changed the length of the day for messing > with our time-keeping? > http://www.sciencedaily.com/releases/2010/03/100302084522.htm > > (And, finally, for anyone who really wants to despair at the whole thing, > I give you "The Long, Painful History of Time", which is the best write-up > I know of about the engineering difficulties of the topic: > http://naggum.no/lugm-time.html > ) None of this would be a problem if we'd just switch to decimal time in a single timezone and call it a day. -- Pete -- SLUG - Sydney Linux User's Group Mailing List - http://slug.org.au/ Subscription info and FAQs: http://slug.org.au/faq/mailinglists.html
Time Pedantry (was Re: [SLUG] Which bank doesn't use Linux servers?)
Nick Andrew writes: > On Thu, Apr 01, 2010 at 03:39:00PM +1100, Daniel Pittman wrote: > >> If it was my call, I would probably do the same thing. Way too many >> developers get simple things like "this day has no 2:30AM" or "this day has >> two 2:00AMs" wrong. > > That's why Daylight Savings is fundamentally evil. Too much time data is > stored in non-canonical formats. ...but the real question is if we love or hate the GMT/UTC difference, and 23:59:61? Daniel Also, do we hate the earthquake that changed the length of the day for messing with our time-keeping? http://www.sciencedaily.com/releases/2010/03/100302084522.htm (And, finally, for anyone who really wants to despair at the whole thing, I give you "The Long, Painful History of Time", which is the best write-up I know of about the engineering difficulties of the topic: http://naggum.no/lugm-time.html ) -- ✣ Daniel Pittman✉ dan...@rimspace.net☎ +61 401 155 707 ♽ made with 100 percent post-consumer electrons -- SLUG - Sydney Linux User's Group Mailing List - http://slug.org.au/ Subscription info and FAQs: http://slug.org.au/faq/mailinglists.html