New SICP study group.

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inimino

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Oct 28, 2009, 2:44:08 PM10/28/09
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Just a heads-up to those still on this list, there is a new
group working through SICP, meeting on IRC every day and
doing two exercises. They are currently up to Exercise 1.34
and have some good momentum going. If anyone wants to join
the new group, this is a good time to do it.

The group meets in ##club-classroom on freenode at 1900Z
every day.

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http://inimino.org/~inimino/blog/

Matthew Forr

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Oct 29, 2009, 9:50:00 AM10/29/09
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So by 1900z time you mean 2pm Eastern time?

inimino

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Oct 29, 2009, 12:10:09 PM10/29/09
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Matthew Forr wrote:
> So by 1900z time you mean 2pm Eastern time?

No, currently "Eastern time" means EDT, so that would
be 3 PM, unless you live in a state (or part of a state)
that doesn't use DST.

You can see what this is in your local time zone here:

http://www.timeanddate.com/worldclock/fixedtime.html?month=10&day=29&year=2009&hour=19&min=0&sec=0

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http://inimino.org/~inimino/blog/

Pas Besoin

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Oct 29, 2009, 12:48:50 PM10/29/09
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If I recall correctly -- but I may be wrong -- we are in that
transition period where (most of) Western Europe has moved back to
standard time but the U.S. is still on daylight savings time. Thus
the 4 hour difference between Greenwich (~= Zulu (Z)) and Eastern.
The U.S. moves back to standard time this coming Saturday night /
Sunday morning, at which point the difference between Greenwich and
Eastern will return to 5 hours.

inimino

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Oct 29, 2009, 1:57:04 PM10/29/09
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Pas Besoin wrote:
> If I recall correctly -- but I may be wrong -- we are in that
> transition period where (most of) Western Europe has moved back to
> standard time but the U.S. is still on daylight savings time.

"Z" refers to UTC (or the older GMT), which is constant and does
not observe any summer time or any other political seasonal
adjustments. So the US still being on DST is relevant to the
difference between US Eastern time and UTC (or Z), but whether
Western Europe is on summer time is not relevant. (In other
words, GMT is not necessarily the current time in Greenwich).

> Thus
> the 4 hour difference between Greenwich (~= Zulu (Z)) and Eastern.
> The U.S. moves back to standard time this coming Saturday night /
> Sunday morning, at which point the difference between Greenwich and
> Eastern will return to 5 hours.

The new group has some people in and some out of the US, so what
they decide to do with the DST change remains to be seen. :-)

Pas Besoin

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Oct 29, 2009, 2:07:01 PM10/29/09
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I was a little fuzzy on that point, but in a hurry and hoping to get
the gist across. There is a short period of time in the fall where
Europe has moved back to standard time but the U.S. has not. Leaving
aside Greenwich and UTC (although I did mean ~= to mean approximately
equal, but was still not right about whether Greenwich would reflect
DST or not), during that time, someone comparing a clock on the pub
wall in England to one in a bar in New York will see 4 hours'
difference. (So when the pub closes, hop a quick flight to NYC and
maybe you can make last call. ;-)

Sorry for any confusion/misinformation on my part.
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