bug in inets or erlang!

Jouni Rynö <>
Wed Nov 30 11:00:28 CET 2005


On Wed, 2005-11-30 at 10:07 +0100, Ulf Wiger (AL/EAB) wrote:
> I agree that, given the type of input argument, it's
> not obvious why this function should stop working 
> before some arbitrary point in time - if it's not 
> the beginning of time, but I assume that would be
> {{0,0,0},{0,0,0}}.
> 

There's no year zero in the time system we are using, only -2, -1, 1,
2 ... 
 
> OTOH, Coordinated Universal Time (UTC) didn't 
> exist before 1972, so what would be a correct 
> return value before then?
> 
> Also time zones haven't always looked the same.
> The U.S. introduced four time zones on Nov. 18,
> 1883. So chances are that any conversion from 
> UTC to localtime given very old dates would have
> to operate on timezone definitions that didn't 
> exist at the time. What, then, is the significance
> of the result?
> 
> /Uffe 

And before that towns used their own local time ...

One could use julian data, but event that goes a limited amount of time
to the past. Fortunately, not so far, that the drifting of the
continents is not significant ...

"Julian Day or Julian Date is a continuous count of days and fractions,
started in January 1st 4713 BC (-4712 in the astronomical almanac) at
Greenwich mean noon (12 UT)"


Jouni
-- 

  Jouni Rynö                            mailto://Jouni.Ryno@fmi.fi/
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