We should start preparing panicky press releases. This could be another Y2K boom if we play it right.

Hi,

As the Daylight Savings Time varies quite radically within the United States (let alone elsewhere), a lookup table for applications is probably a good idea anyways regardless of the new law. A related note: I prefer to have the database systems running on UTC time and let the client application handle the conversion to the appropriate time zone.

use Time::Local;
my $time = timelocal(0,0,12, (localtime)[3,4,5]);
[download]

I'm sorry, I don't understand. What is a "neutral" time?

A "neutral" time is an hour of the day that will not cause you skip or double a day when going over a daylight savings time boundary.

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Jeff japhy Pinyan, P.L., P.M., P.O.D, X.S.: Perl, regex, and perl hacker
How can we ever be the sold short or the cheated, we who for every service have long ago been overpaid? ~~ Meister Eckhart

Hi,

When dealing with a small set of time zones (Eastern through Pacific for example) one can drop the hours to determine the number of days between two datetimes.

2:05pm would become 12 noon. 1am would become 12 noon. So the # of days between 05:02 Aug 4, 2005 and 10:08pm Aug 10, 2005 is 6 days not 6.xxx days

The granularity is a day so a small number of calculations in this manner would provide fairly accurate # of days. With a large number of calcuations, the truncating of the hours will start to become an issue.

It's a quick and dirty hack that is often sufficient for many things. We often will drop the hours when we count back in our heads.

Jason L. Froebe

Team Sybase member

No one has seen what you have seen, and until that happens, we're all going to think that you're nuts. - Jack O'Neil, Stargate SG-1

The one thing I keep thinking about is calculations of elapsed time between two dates, esp if the older date is pre 1987 DST changes and the second date is post 2007 changes and one of those are not in GMT.

Hi,

Thanks :) I grew up knowing it with the extra s. You are correct and to our credit, many text books list it one way or the other. (in some cases, it will be listed with the extra s in one section and without in another.

Thanks for letting us know the correct spelling. I definitely ++ your post :)

Jason L. Froebe

Team Sybase member

No one has seen what you have seen, and until that happens, we're all going to think that you're nuts. - Jack O'Neil, Stargate SG-1

To further my reputation for inserting tangential trivia instead of just answering a question, let me mention that it is Daylight Saving Time, not Savings.

Well if you're going to be picky, surely a compound preposed adjective should have a hyphen in it:

• "daylight-saving time" parses as "time with daylight saving", which is presumably what is intended.
• "daylight saving time" parses as "saving time with daylight". I've no idea what "saving time" is (as a noun), but perhaps it's something to do with that bank you mentioned ...

To put it in Perl terms: adjectives are right-associative.

Smylers

Or to be even more picky, the use of a hyphen is only appropriate when a non-adjective forms part of a compound adjective. The normal but less readable way of denoting two or more adjectives is to use a comma between adjectives. This example, using non-adjectives in the mix, shows where a hyphen is required, where a comma is required and where neither is required (where an adverb describes the adjective):

Really picky, showing-the-commas, daylight-saving time.

-S

One world, one people

To be absolutely picky: any proper noun is only properly spelled and pronounced when it is spelled and pronounced the way that the owner wants it spelled and pronounced. Thus, grammar has nothing to do with it.

To put it in Perl terms: Global symbol "Daylight Savings Time" requires explicit package name. Execution aborted due to compilation errors.

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