Read this from the as.POSIXct help page more carefully:
"Usage
as.POSIXct(x, tz = "", ...)"
"tz
A timezone specification to be used for the conversion, if one is
required. System-specific (see time zones), but "" is the current
timezone, and "GMT" is UTC (Universal Time, Coordinated)."
--
David Winsemius
On Mar 14, 2009, at 9:52 AM, Neotropical bat risk assessments wrote:
I am working with time-date data to plot temporal activity.
I would like to create a "template" to repeat the date and time for
all potential data sets that may have differing time zone origins.
Reading the > ?strptime help section I note that time zone is a
variable to add.
Looking at the output of a sample data set
Species Location Date Time
1 Sppaaa One 1/13/2009 17:00
2 Sppaaa One 1/13/2009 18:00
3 Sppaaa One 1/13/2009 19:00
4 Sppaaa One 1/13/2009 20:00
5 Sppaaa One 1/13/2009 21:00...
in order to understand how R is handling this and using:
> All$Time <- as.POSIXct(strptime(as.character(d$Time), "%H:%M"))
> All$Time
[1] "2009-03-14 17:00:00 CST" "2009-03-14 18:00:00 CST"
[3] "2009-03-14 19:00:00 CST" "2009-03-14 20:00:00 CST"
[5] "2009-03-14 21:00:00 CST" "2009-03-14 22:00:00 CST"
It appears that the default is using CST and this is I assume based
on my system setting for my PC time.
Is there a way to NOT have it do this as the data I am processing
are from a different time zone.
Tnx
Bruce
David Winsemius, MD
Heritage Laboratories
West Hartford, CT
______________________________________________
R-help@r-project.org mailing list
https://stat.ethz.ch/mailman/listinfo/r-help
PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.
