# [conspire] Calculating iCal dates

Tony Godshall tony at of.net
Thu Jul 30 17:27:33 PDT 2009

```>> BEGIN:VEVENT
>> UID:20090805T020000Z-58d96332c8cd1797ff3ec39c35f8ac63 at lugod.org
>> DTSTART:20090805T020000Z
>> DTEND:20090805T040000Z
>> SUMMARY:LUGOD social gathering. -- http://www.lugod.org/meeting/
>> END:VEVENT
>
> So this event begins at 2 a.m. and ends at 4 a.m.? It's mainly this part of
> the timestamp which is causing me problems:

Z = zulu time?

We are at GMT-8 most of the year and, what, GMT-7 in the summer?

2+24-8=18 = 6PM Pacific Std
2+24-7=18 = 7PM Pacific Std

Google Calendar shows it as 7-9 pm, so I think that's it.

Oh, and it's Aug 4, not Aug 5!  Since we crossed midnight!

Then again, I could actually bother to read the spec.

> BEGIN:VEVENT
> ...
> DTSTART;TZID=US/Pacific:20090811T013000Z
> DTEND;TZID=US/Pacific:20090811T040000Z
> ...
> END:VEVENT
>
> Same result if I leave out the timezone part. The event is supposed to be
> from 6:30 - 9:00 p.m.

0130 GMT would thus be 1830 Pacific (GMT-7).  0130-0700 is 1830 the prior day

Tony

```