Hello I have this little dataset, my goal is create one column in the data.frame with between the diference DataTime and Duration. I'm using the next code to make do this
TIME_STAMP SESSIONTIME Time TimeStart 1162343932 8320 2006-10-31 19:01:34 2006-10-31 16:42:54 1162343215 592 2006-10-31 19:02:04 2006-10-31 18:52:12 1162341465 11875 2006-10-31 19:02:27 2006-10-31 15:44:32 1162339324 118 2006-10-31 19:03:01 2006-10-31 19:03:03 1162339381 2 Dataset$Time<-as.POSIXlt(TIME_STAMP, origin="1970-01-01", tz="America/New_York") temp1<-Dataset$Time-Dataset$SESSIONTIME Dataset$TimeStart<-as.POSIXlt(temp1, origin="1970-01-01", tz="America/New_York") I don't understand why changed the data in column TimeStar on 4 register Thanks -- View this message in context: http://r.789695.n4.nabble.com/Subtract-Date-Between-columns-tp4474466p4474466.html Sent from the R help mailing list archive at Nabble.com. ______________________________________________ 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.