Re: Time confusion?

[Vic Norton]

I don't think the problem has anything to do with time zones, Paul. The line

   octave> strptime('23-Feb-04', "%e-%b-%y")

produces a time structure with

   mday = 23
   mon = 1
   wday = 0
   year = 104

The weekday here corresponds to Sunday, and there was no Sunday, 
February 24, 2004.


There is really nothing special about '23-Feb-04'. Right now it is 
Thursday, March 11, 2004 here and Friday, March 12, 2004 in New 
Zealand. No matter, wday = 0 for either

   octave> strptime('11-Mar-04', "%e-%b-%y")

or

   octave> strptime('12-Mar-04', "%e-%b-%y")

Everyday is Sunday to strptime. It must be retired.


It does appears that you can always get the correct (local) time 
structure from the composite function localtime(mktime(strptime())). 
Thus

   octave> localtime(mktime(strptime('11-Mar-04', "%e-%b-%y")))

produces the correct

   ans =
   {
     hour = 0
     isdst = 0
     mday = 11
     min = 0
     mon = 2
     sec = 0
     usec = 0
     wday = 4
     yday = 70
     year = 104
     zone = EST
   }

whereas

   octave> strptime('11-Mar-04', "%e-%b-%y")

produces the impossible

   ans =
   {
     hour = 0
     isdst = 0
     mday = 11
     min = 0
     mon = 2
     sec = 0
     usec = 0
     wday = 0
     yday = 0
     year = 104
     zone =
   }


As you will notice strptime produces no time zone at all on my 
Octave, version 2.1.50.


Regards,

Vic


At 7:09 PM -0500 3/10/04, Paul Kienzle wrote:
>  On Mar 10, 2004, at 11:45 AM, Vic Norton wrote:
> >  Start with the date 23-Feb-04. That was a Monday. Do strptime to 
> > get a TM_STRUCT and then do strftime to that. This changes the day. 
> > Now 23-Feb-04 is Sunday.
>
>  It can if it is in a different time zone.  E.g., start at 12:00AM 
> on Monday, no time
>  zone specified.  Set zone to EST.   If your time zone is CST, 
> 12:00AM on Monday
>  in EST is really 11:00PM on Monday in CST.
>
>  print out the full date and time, including time zone, on 
> tm_struct1 and tm_struct2.
>
>         strftime ("%r (%Z) %A %e %B %Y",tm)
>
>  Paul Kienzle
>  address@hidden
>
>
>
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--
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|  Vic Norton      2002 CapoNord   HSTA 5992  DOD 43403
| (419)353-8399    1997 KLR650     STOC 037   AMA 594102
*------* http://vic.norton.name/moto



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