From ripley@stats.ox.ac.uk  Fri Feb 21 08:17:03 2003
From: ripley@stats.ox.ac.uk (ripley@stats.ox.ac.uk)
Date: Fri Feb 21 08:17:03 2003
Subject: [Rd] POSIX problem in New Zealand (PR#2570)
In-Reply-To: <200302210555.h1L5tm35026463@pubhealth.ku.dk>
Message-ID: <Pine.LNX.4.44.0302210708350.19969-100000@gannet.stats>

What exactly is the problem?  Those appear to be the same time, in 
different time zones.  Is the problem that you are in the N Hemisphere
(your email address is) trying to use S Hemisphere times on an OS
that does not support pre-1970 times?

You seem to be confusing the time and how it is printed.  What do you 
want to do with these times?

On Fri, 21 Feb 2003 arnima@u.washington.edu wrote:

> Full_Name: Arni Magnusson
> Version: 1.6.2
> OS: Windows XP
> Submission from: (NULL) (210.48.49.68)
> 
> 
> Hi there. I'm experiencing unexpected behaviour from as.POSIXct:
> 
> > as.POSIXct("1969-12-24")
> [1] "1969-12-23 23:00:00 New Zealand Standard Time"
> > as.POSIXlt("1969-12-24")
> [1] "1969-12-24"
> > as.POSIXlt("1969-12-24")+1
> [1] "1969-12-23 23:00:01 New Zealand Standard Time"
> 
> 
> My friend on the US West Coast tells me he has not encountered this problem.
> I've read some of the glibc discussion, but I believe that's not relevant for
> Windows XP. I also read that tz="GMT" could circumvent some problems, but not
> mine:
> 
> > as.POSIXct("1969-12-24 12:00:00", "GMT")
> [1] "1969-12-25 New Zealand Standard Time"

That's correct.  You need to *print* in GMT too.

> If I can get around this problem, I'd prefer using POSIX rather than the date or
> chron classes. Perhaps a Windows environment variable is the key?

-- 
Brian D. Ripley,                  ripley@stats.ox.ac.uk
Professor of Applied Statistics,  http://www.stats.ox.ac.uk/~ripley/
University of Oxford,             Tel:  +44 1865 272861 (self)
1 South Parks Road,                     +44 1865 272866 (PA)
Oxford OX1 3TG, UK                Fax:  +44 1865 272595



[Rd] POSIX problem in New Zealand (PR#2570)
ripley@stats.ox.ac.uk