Re: [R] isdst

From: Prof Brian Ripley <ripley_at_stats.ox.ac.uk>
Date: Fri 07 Oct 2005 - 03:05:48 EST

On Thu, 6 Oct 2005, Omar Lakkis wrote:

> Can someone, please, explain the difference is results below (notice
> the isdst value)

Timezones. (That is carefully documented on the help page for as.POSIXlt.)

>> unlist(as.POSIXlt('2005-7-1'))

> sec min hour mday mon year wday yday isdst
> 0 0 0 1 6 105 5 181 1
This is midnight on 2005-07-01 in your timezone, which presumably does
have DST and it was in force then.
>> unlist(as.POSIXlt(as.Date('2005-7-1')))

> sec min hour mday mon year wday yday isdst
> 0 0 0 1 6 105 5 181 0
This is midnight on 2005-07-01 in UTC (which does not have DST). -- 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 ______________________________________________
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https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html Received on Fri Oct 07 03:19:07 2005

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