[Numpy-discussion] timezones and datetime64

Francesc Alted francesc@continuum...
Thu Apr 4 09:37:45 CDT 2013


On 4/4/13 1:52 AM, Chris Barker - NOAA Federal wrote:
> Thanks all for taking an interest. I need to think a bot more about
> the options before commenting more, but:
>
> while we're at it:
>
> It seems very odd to me that datetime64 supports different units
> (right down to  attosecond) but not different epochs. How can it
> possible be useful to use nanoseconds, etc, but only right around
> 1970? For that matter, why all the units at all? I can see the need
> for nanosecond resolution, but not without changing the epoch -- so if
> the epoch is fixed, why bother with different units?
<snip>

When Ivan and me were discussing that, I remember us deciding that such 
a small units would be useful mainly for the timedelta datatype, which 
is a relative, not absolute time.  We did not want to make short for 
very precise time measurements, and this is why we decided to go with 
attoseconds.

-- 
Francesc Alted



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