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one more help please how to convert GMT to central time?

Posted: Tue Sep 25, 2007 10:52 am
by tini
What is GMT?
and how can GMT convert to central time?
could someone please help.
Thanks
:oops:

Posted: Tue Sep 25, 2007 12:33 pm
by chulett
Something like that I would simply Google for. GMT is 'Greenwich Mean Time' and is basically the zero point for all timezone offsets. 'Central' is defined as GMT-6 so you subtract six hours from GMT to get Central.

And then there's Daylight Saving Time...

Posted: Tue Sep 25, 2007 5:18 pm
by ray.wurlod
And then there's your assumption that tini is in the USA...
:wink:

Australia also has Central Time, defined as GMT +8.5 hours (some of it goes onto daylight saving in the Southern summer, some of it does not).

There are some SDK Transforms for converting GMT, if my memory serves me correctly. You can also use System(99), which returns the number of seconds since midnight GMT on 1970-01-01 and Oconv(thedate, "DZ") to return the time zone, and make some formula based upon these.

The switch to and from daylight saving is never easy, particularly in those countries that move it around for political convenience or otherwise manage it in a non-uniform fashion.

Posted: Tue Sep 25, 2007 7:03 pm
by chulett
ray.wurlod wrote:And then there's your assumption that tini is in the USA... :wink:
Well, yah... duh, isn't everyone? :wink:

In my defense, I popped open my Windows Time Zone dialog on my PC and pulled down the entire list of time zones. There was only one labelled as Central, so thought the assumption was safe. Unfortunately, it has no "+8.5" entry but does show "+8.0" as "Perth". FWIW.

Posted: Tue Sep 25, 2007 11:23 pm
by ray.wurlod
I checked mine, and it's showing GMT +09:30 (which is actually correct at the moment).

Posted: Sun Sep 30, 2007 9:25 pm
by tini
Thank you for all your help but I really don't get it. :oops: :oops: :oops:
so I should take
GMT - 6 right?

and then how do I handle Daylight saving time? like Chulett said?

Hi, ray.wurlod.
What do you mean by GMT +09:30 (which is actually correct at the moment).?
Could you explain more please :( :(
Thanks
tini

Posted: Sun Sep 30, 2007 9:27 pm
by ray.wurlod
What I meant was that Central time in Australia is currently 9h30 ahead of GMT.

This has nothing whatsoever to do with the Central time zone in the USA.

Posted: Sun Sep 30, 2007 11:02 pm
by tini
Thanks ray.wurload.
Sorry Iam asking so much

Posted: Mon Oct 01, 2007 12:45 am
by ray.wurlod
But you never did get an answer about daylight saving time. Nor is there a ready answer. You could interrogate the system's time zone setting, and trust that it has been set correctly. You could rely on the legislation about the changeover dates, but these may change in future (they are changing this coming summer in some states in Australia, for example).

Posted: Tue Oct 23, 2007 11:46 pm
by tini
If the input is
Char 14 (20060911150001) but it's represent of GMT time.
How do I convert it to Central time? at this point I don't care about Daylight Savings.

What I did is I take I convert to (StringToTimeStamp - 5) but it didn't work. :oops: :cry:

Please help.
Thanks

Posted: Wed Oct 24, 2007 12:24 am
by ArndW
The -5 you used subtracted 5 seconds from the TimeStamp; you need to subtract (5*60*60) from the timestamp.