library(chron) Lines <- " ID Target Actual Date Time 1 2030 0 -57.0 12/20/08 17:03:00 2 2030 90 90.0 12/20/08 18:41:00 3 2030 45 43.8 12/21/08 14:36:00 4 2030 0 -23.8 12/21/08 19:30:00 5 2030 90 90.2 12/21/08 21:48:00 6 2030 45 48.6 12/22/08 13:02:00"
DF <- read.table(textConnection(Lines), header = TRUE, as.is = TRUE) dt <- chron(DF$Date, DF$Time) DF$pdate <- format(as.Date(dt)) DF$ptime <- format(dt - dates(dt)) This gives: > DF ID Target Actual Date Time pdate ptime 1 2030 0 -57.0 12/20/08 17:03:00 2008-12-20 17:03:00 2 2030 90 90.0 12/20/08 18:41:00 2008-12-20 18:41:00 3 2030 45 43.8 12/21/08 14:36:00 2008-12-21 14:36:00 4 2030 0 -23.8 12/21/08 19:30:00 2008-12-21 19:30:00 5 2030 90 90.2 12/21/08 21:48:00 2008-12-21 21:48:00 6 2030 45 48.6 12/22/08 13:02:00 2008-12-22 13:02:00 See R News 4/1 for info on dates. Also, why do you want to store formatted dates in the first place? On Sat, Mar 14, 2009 at 8:52 AM, Aimin Yan <aim...@iastate.edu> wrote: > I have a data set like this: > >> head(FormatedData) > ID Target Actual Date Time > 1 2030 0 -57.0 12/20/08 17:03:00 > 2 2030 90 90.0 12/20/08 18:41:00 > 3 2030 45 43.8 12/21/08 14:36:00 > 4 2030 0 -23.8 12/21/08 19:30:00 > 5 2030 90 90.2 12/21/08 21:48:00 > 6 2030 45 48.6 12/22/08 13:02:00 > > I wan to convert the format of Date and Time, so I did this: > > pdate <- as.POSIXct(strptime(FormatedData$Date,"%m/%d/%Y")) > ptime <- as.POSIXct(strptime(FormatedData$Time,"%H:%M:%S")) > > but I get the following format: > >> head(NewFormatedData) > ID Target Actual Date Time pdate ptime > 1 2030 0 -57.0 12/20/08 17:03:00 8-12-20 2009-03-14 17:03:00 > 2 2030 90 90.0 12/20/08 18:41:00 8-12-20 2009-03-14 18:41:00 > 3 2030 45 43.8 12/21/08 14:36:00 8-12-21 2009-03-14 14:36:00 > 4 2030 0 -23.8 12/21/08 19:30:00 8-12-21 2009-03-14 19:30:00 > 5 2030 90 90.2 12/21/08 21:48:00 8-12-21 2009-03-14 21:48:00 > 6 2030 45 48.6 12/22/08 13:02:00 8-12-22 2009-03-14 13:02:00 > > in ptime, it includes the current date, I don't want this, > actually, I want to have the following formats: > > ID Target Actual Date Time pdate ptime > 1 2030 0 -57.0 12/20/08 17:03:00 2008-12-20 17:03:00 > 2 2030 90 90.0 12/20/08 18:41:00 2008-12-20 18:41:00 > 3 2030 45 43.8 12/21/08 14:36:00 2008-12-21 14:36:00 > 4 2030 0 -23.8 12/21/08 19:30:00 2008-12-21 19:30:00 > 5 2030 90 90.2 12/21/08 21:48:00 2008-12-21 21:48:00 > 6 2030 45 48.6 12/22/08 13:02:00 2008-12-22 13:02:00 > > Does anyone know how to do these? > > ______________________________________________ > 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. > ______________________________________________ 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.