Does a day start at 1:00 AM everwhere?
mpetrides at earthlink.net
Fri Oct 27 11:34:26 EDT 2006
make that 2010 not 20010 :-)
On Oct 27, 2006, at 10:20 AM, Marian Petrides wrote:
> While we are on the topic of dates, I've been thinking about
> creating a "countdown" calendar, clocking the number of days
> remaining between today's date and some future date (March 31,
> 20010 specifically). Any tips on how I can do this? Do I have to
> convert dates into seconds in order to subtract one from the
> other? Thanks.
> On Oct 27, 2006, at 9:49 AM, Ken Ray wrote:
>> On 10/27/06 7:52 AM, "Mark Powell" <mark_powell at symantec.com> wrote:
>>> I have a user-specified date. I want to convert it to seconds and
>>> factor in 86400 to establish the range of seconds for that date,
>>> so that
>>> I can compare a file's creation date to determine whether that
>>> file was
>>> created on that specified day. The problem is I am not sure what is
>>> used as the starting point for a date's seconds counter. At 6:42
>>> morning, I ran this:
>>> put the short date into theDate
>>> convert theDate to seconds
>>> put ((the seconds - theDate) / 3600)
>>> and got 4.710556, which suggests that a date starts at 1:00 AM
>>> and not
>>> midnight. Is this accurate? And more importantly, is this the
>>> way the
>>> computation would be handled on any client machine anywhere?
>> Welcome to the wonderful world of dates in Revolution!
>> Seriously - Many of us have struggled with date arithmetic in Rev
>> as it
>> relates to other parts of the world. The short answer is "no", it
>> is not
>> always 1:00 AM everywhere when you convert a date to seconds and
>> back again.
>> In fact for me, I get 2:00 AM.
>> Date conversions give you different results depending on a number of
>> factors: is Daylight Saving Time (DST) or Summer Hours currently
>> observed? What hemisphere are you on? Are you looking at a date
>> that is
>> "across" a DST boundary (such as the current date being in March
>> and you're
>> looking at a date in May, which is across the DST "boundary" in
>> I wish it were easier, but it's not... in your *specific*
>> though, if you're just trying to compare one date to another, you
>> can strip
>> off the time from the file creation date, and then convert the
>> date and the date from the file creation to seconds and compare -
>> should be the same:
>> put fld "UserDate" into tUserDate
>> put fld "FileCreationDateTime" into tFileDateTime
>> put word 1 of tFileDateTime into tFileDate
>> -- assumes a datetime where the date and time are separate by a
>> convert tUserDate to seconds
>> convert tFileDate to seconds
>> if tUserDate = tFileDate then
>> answer "Same day"
>> answer "Different day"
>> end if
>> Will this work for you?
>> Ken Ray
>> Sons of Thunder Software, Inc.
>> Web site: http://www.sonsothunder.com/
>> Email: kray at sonsothunder.com
>> use-revolution mailing list
>> use-revolution at lists.runrev.com
>> Please visit this url to subscribe, unsubscribe and manage your
>> subscription preferences:
> use-revolution mailing list
> use-revolution at lists.runrev.com
> Please visit this url to subscribe, unsubscribe and manage your
> subscription preferences:
More information about the use-livecode