On Wed, 03 Jul 2013, Ye Lin <ye...@lbl.gov> writes: > Hey All, > > I want to standardize my timestamp which is formatted as hh:mm:ss > > My data looks like this: > > Date Time > 01/01/2013 00:09:01 > 01/02/2013 00:10:14 > 01/03/2013 00:11:27 > 01/04/2013 00:12:40 > 01/05/2013 00:13:53 > 01/06/2013 00:15:06 > 01/07/2013 00:16:19 > 01/08/2013 00:17:32 > 01/09/2013 00:18:45 > 01/10/2013 00:19:58 > > Dataset <- structure(list(Date = c("01/01/2013", "01/02/2013", > "01/03/2013", > "01/04/2013", "01/05/2013", "01/06/2013", "01/07/2013", "01/08/2013", > "01/09/2013", "01/10/2013"), Time = c("00:09:01", "00:10:14", > "00:11:27", "00:12:40", "00:13:53", "00:15:06", "00:16:19", "00:17:32", > "00:18:45", "00:19:58")), .Names = c("Date", "Time"), class = "data.frame", > row.names = c(NA, > -10L)) > > I would like to change all the records in "Time" column uniformed as > hh:mm:00, then the output would be this: > > Date Time > 01/01/2013 00:09:00 > 01/02/2013 00:10:00 > 01/03/2013 00:11:00 > 01/04/2013 00:12:00 > 01/05/2013 00:13:00 > 01/06/2013 00:15:00 > 01/07/2013 00:16:00 > 01/08/2013 00:17:00 > 01/09/2013 00:18:00 > 01/10/2013 00:19:00 > > Thanks for your help!
Since your dates and times are character vectors, you can do this: substr(Dataset$Time, 7, 8) <- "00" If you want to treat them as actual dates and times, you need to convert them into one of R's date/time classes (see ?DateTimeClasses): timestamp <- as.POSIXlt(paste(Dataset$Date, Dataset$Time), format = "%m/%d/%Y %H:%M:%S") timestamp$sec ## [1] 1 14 27 40 53 6 19 32 45 58 timestamp$sec <- 0 > > [[alternative HTML version deleted]] > Please send only plain-text mails to this list. -- Enrico Schumann Lucerne, Switzerland http://enricoschumann.net ______________________________________________ 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.