Daylight Savings Time



#2

Three cheers for the 200LX !!! It flawlessly changed the US timezones.

For the unaware readers (and also current & future 200LX users) reading this:

You should have updated your file C:\_DAT\TIMEZONE.DAT with

Northern
3:8-14 6 1:00
11:1-7 6 0:00

http://isc.sans.org/diary.html?storyid=5971

Best regards,

Peter A. Gebhardt


#3

I suppose it should be possible for me to write a program to do that in the 48GX, too.


#4

Here is my version of DST for a 48G. It's part of another program, but you can reformat the code to your needs.

Pgm 'EDST' sets DST global to 1 or 0 for Daylight Savings
---------------------------------------------------------
«
-> m d y «
y 100 / IP @century on stack
y 100 MOD DUP @ yy on stack twice
4 / IP + SWAP 4 MOD 5 * + 7 MOD 30 SWAP - @ Last Sunday April
DUP 22 - 7 MOD 1 + @ First Sunday April
10 + DUP 14 IF < THEN 7 - END @ Second Sunday March
SWAP 5 + DUP 31 > «7 -» IFT @ Last Saturday October
-> b e «
m 100 * d + DUP 300 b + >= SWAP 1000 e + <= AND 'DST' STO
» » »

In program EDST:
Daylight Savings originally started on the last Sunday in April.
Then it was moved to the first Sunday in April.
Than it was moved again the second Sunday in March.
It was easier for me each time to just adust the previously
calculated date.


#5

Well, I should have previewed that. It didn't honor my new_lines, But, how do I force them?

#6

Pgm 'EDST' sets DST global to 1 or 0 for Daylight Savings --------------------------------------------------------- 
« -> m d y
« y 100 / IP @century on stack
y 100 MOD DUP @ yy on stack twice
4 / IP + SWAP 4 MOD 5 * + 7 MOD 30 SWAP - @ Last Sunday April
DUP 22 - 7 MOD 1 + @ First Sunday April
10 + DUP 14 IF < THEN 7 - END @ Second Sunday March
SWAP 5 + DUP 31 > «7 -» IFT @ Last Saturday October
-> b e « m 100 * d + DUP 300 b + >= SWAP 1000 e + <= AND 'DST' STO » » »

Thanks!

P.S. you use [pre] before, and [/pre] to end the line editor

Edited: 8 Mar 2009, 8:47 p.m.

#7

Quote:
In program EDST: Daylight Savings...

First, several clarifications:

1. In the US, the term is Daylight Saving Time (not "Savings").

2. DST in the Eastern Time Zone is abbreviated "EDT". "EDST" would cause ambiguity with Standard Time (EST), and looks like a typo, since "D" and "S" are adjacent to each other on the standard keyboard.


The calendar extension of Daylight Saving Time several years ago in the US was largely a gimmick, as far as I'm concerned -- a so-called "energy-saving" measure that doesn't require any real sacrifice or commitment to save energy.

From Winter 1940-July 1945 during WWII, Great Britain observed year-round "Summer Time" DST, and a 2-hour-advanced British Double Summer Time during the summers. This actually made sense, as a significant proportion of electrical load was incandescent lighting, and the advanced clock helped to better match daylight hours to people's waking hours. This also lessened the impact of summer blackouts intended to discourage nighttime air raids.

In the US, however, the average climate is considerably warmer. In this era, lighting typically is efficient fluorescent and a significant proportion of electrical load is air conditioning -- both at home and in the workplace or school. In the heart of summer, keeping people awake and active during the warmer evening hours, instead of the cooler morning hours, does not necessarily save energy. This is why hot-climate Arizona (outside of Navajo Nation) does not observe DST.

-- KS


Edited: 9 Mar 2009, 4:00 p.m. after one or more responses were posted


#8

It is my recollection that in the U.S., originally (1950's) it was not about energy saving, but rather recreation.

Supposedly the "blue collar" workers all got off work at 4:00 pm, and during the summer months they would all make use of the extra hour of daylight on a weekday afternoon to go fishing or play pick-up baseball.

Well, now, thanks to "free trade", and Sam Walton, we no longer have any blue collar workers, and since Karl has just proven that it really doesn't save any energy, maybe we can do away with the d**n thing.

Right.


#9

Quote:
... it was not about energy saving, but rather recreation. ...

As I remember it from rural Minnesota in the 1940's and later the townspeople loved it for the recreation but the farmers hated it. The farmers talked about standard time as "God's time".

Palmer


#10

I never understood the "farmer argument." Can't a farmer can get up any time he wants to tend to his fields, and go to bed whenever he wants, regardless of what the clock says?


#11

A good friend of mine is a farmer. Your right in that he'll start work at daylight, regardless of what the clock says. He says the problem the farmer's have (or at least he has) with daylight savings time is that the farm machinery/repair/parts suppliers close earlier. So if he has problems with his equipment in the field and the parts house is closed, he may loose several hours of daylight work since he can't get the parts for repair.

I'm originally from Indiana, where over the years we have had several implementarions of daylight savings time. In high school, we lived right on the boarder between two time zones. At home, we were on daylight savings time, while the high school I atended was on standard time. So it was important to state which time reference whenever you set up a meeting time. We took to refering to daylight savings time as "Fast Time" and standard time as "Slow Time". So we'd say, I'll meet you on Wednesday morning at 9 Fast Time or 9 Slow Time. That way there never was a problem knowing which time a person was referring to.

I remember a period in the 70's, where the county I was living in decided to dictate the "Official" time for the county. They chose Standard Time. But the county was next to a large city in the neighboring State that was on daylight savings time. Since a large majority of the people in the county worked in the neighboring city, the county ended up placing an "Official Clock" in the courthouse that displayed the official time. But every one, including the court house emplyees use Daylight Savings Time as their standard clocks. Sounds confusing, but it's really not. As long as everyone uinderstands each other, then there's no confusion.

Bill


#12

Bill,
Thanks for your comments.

Quote:
He says the problem the farmer's have (or at least he has) with daylight savings time is that the farm machinery/repair/parts suppliers close earlier. So if he has problems with his equipment in the field and the parts house is closed, he may loose several hours of daylight work since he can't get the parts for repair.

I can see that, but, I would expect that such businesses would adjust their operating hours to accommodate their customers and stay open an hour later as soon as DST kicks in. Of course, if everyone just adjusted when they did things relative to the clock instead of adjusting the clock relative to the sun, that would eliminate the need for DST in the first place.

Quote:
I'm originally from Indiana, where over the years we have had several implementarions of daylight savings time.

I live in a state that neighbors Indiana and have observed Indiana's DST trials over the years. They recently adopted DST on a more-or-less statewide basis. In my opinion, they should have then gone into the Central Time zone where they belong geographically. Since time zones should theoretically be 15 degrees wide, the US Eastern time zone (GMT-5) should extend from 67.5 to 82.5 degrees west longitude, with adjustments as needed for political and social boundaries. Those adjustments are of course not trivial, especially for a state that may span the mathematical border. The Ohio/Indiana border is at 84.8 degrees West longitude, and all of Indiana is west of this line, so it would make a fine political and social boundary. I think they preferred the eastern time zone for social/financial/business reasons, i.e., to be aligned with the east coast.

Just my observations and opinions, no offense to any Hoosiers!


...


#13

Hi Jeff,


Quote:
In my opinion, they should have then gone into the Central Time zone where they belong geographically.


Quote:
I think they preferred the eastern time zone for social/financial/business reasons, i.e., to be aligned with the east coast.

Exactly - well actually more to be aligned with the neighboring large city in adjacent state. There's two main areas - the 60 mile region around Cincinnatti, Ohio; and the 60 mile region around Louisville, KY. A large percentage of people in each of those areas work/compute to the big city. So it makes sense for them to be on the same time zone as where they work and do most of their shopping. Over the years, I lived in both of those areas.

But I always get amused when people mention Indiana's time zones. As long as you remember "Fast Time" versus "Slow Time", you'll do okay. :)

Bill


#14

Quote:
people in each of those areas work/compute to the big city.

Wrong word, but correct for this forum ;-)

I just watched The West Wing episode "24 Hours in America". Josh, Tobey and Donna are left behind by the presidential motorcade in Indiana (!) and miss the train because they unknowingly crossed over to a different time zone. They didn't know about slow and fast time...

#15

Quote:
I can see that, but, I would expect that such businesses would adjust their operating hours to accommodate their customers and stay open an hour later as soon as DST kicks in.

That sounds reasonable but as I remember it that wasn't always the way it happened.

Back in the olden days the primary problem occurred on Saturday night when the farm families came to town to do their weekly shopping and the stores stayed open until 9 PM. But with DST and a 9 PM closing a farmer who worked from sunup to sundown couldn't get his family to town in time to shop. The farmers asked for a 10 PM closing but the townspeople didn't always want to comply.

One year one town tried to stay with 9 PM closing when a nearby town changed to closing at 10 PM. Guess where the farmers shopped. In a short time the town with the 9 PM closing changed it to 10 PM. "The customer is always right!"

Palmer

#16

Karl,

Quote:
1. In the US, the term is Daylight Saving Time (not "Savings").

I'm in the finance business - you know ;-))

Best regards,

Peter A. Gebhardt

#17

For me DST (living n Europe) is wonderful. Why? Easy: During DST, when coming home from work, I have one additional hour of light for my outdoor activities: walking, trekking and photography.

That's why I would like to have DST during the whole year, or, for ordinary people the ordinary working hours should be 6h to 16h instead of 8h to 18h.


#18

Bingo. See my post above.


#19

For my understanding, Patrick was voting for having DST all year, and you, Martin, were voting for dropping it. Bingo?? I vote for Patrick ;-)


#20

Perhaps my response was too terse. I was saying "bingo" to Patrick's verification of the reason for DST, i.e. recreation...


#21

Exactly: recreation.

Or we must get out of the bed at 4 am, do our recreations, then go to work at 8am and when being back from work some more recreations ...

But I prefer to do my recreations AFTER work ;).

That's why it would be nice if our work times could be adapted. But in my case the students would not be happy if school started at 4am ...

Edited: 10 Mar 2009, 2:32 p.m.


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