This works perfect, thank you very much Rui! On Fri, Oct 12, 2012 at 1:35 PM, Rui Barradas <ruipbarra...@sapo.pt> wrote:
> Hello, > > Try the following. > > > dat <- read.table(text=" > > ID group Start_date Time_of_experiment Time_of_end > 1 20209 4 02/02/2009 12:38:00 > 26 30209 3 03/02/2009 12:40:00 13:32:00 > 27 31609 4 03/16/2009 11:28:00 12:26:00 > 28 40609 4 04/06/2009 11:17:00 > 53 42709 4 04/27/2009 11:15:00 9:30:00 > 76 51109 3 05/11/2009 11:51:00 > 101 51809 1 05/18/2009 12:28:00 > 126 62209 3 06/22/2009 11:31:00 > 150 71309 4 07/13/2009 12:12:00 13:37:00 > 173 81009 4 08/10/2009 11:32:00 20:52:00 > ", header=TRUE, fill=TRUE) > str(dat) > > dat$start_time <- with(dat, paste(Start_date, Time_of_experiment)) > dat$Start_of_Experiment <- > as.POSIXct(strptime(dat$start_**time, "%m/%d/%Y %H:%M:%S")) > > #--- Create End_of_Experiment > idx <- dat$Time_of_end != '' > dat$End_of_Experiment <- dat$Start_of_Experiment + 48*60*60 > dat$End_of_Experiment[idx] <- > as.POSIXct(strptime(paste(dat$**Start_date, dat$Time_of_end)[idx], > "%m/%d/%Y %H:%M:%S")) > dat > > > Hope this helps, > > Rui Barradas > Em 12-10-2012 18:59, Charles Determan Jr escreveu: > >> Greetings, >> >> My data set has dates and times that I am working with. Some of the times >> in Time_of_end are blank. This is supposed to dictate that the particular >> experiment lasted 48 hours. I would like to add 48 hours to the start >> Start_of_Experiment for another column as End_of_Experiment including both >> the ones with 48 added and those with early times. I was thinking >> something with a conditional statement but I can't seem to figure out what >> code to use. Any insight would be appreciated. Let me know if there is >> anything else you need. Thanks for your time. >> >> I have Start_of_Experiment in POSIX format for time calculations from the >> following: >> >> data$Start_of_Experiment=as.**POSIXct(strptime(data$start_**time, >> "%m/%d/%Y >> %H:%M:%S")) >> >> Here is a subset of my data. >> >> ID group Start_date Time_of_experiment Time_of_end >> 1 20209 4 02/02/2009 12:38:00 >> 26 30209 3 03/02/2009 12:40:00 13:32:00 >> 27 31609 4 03/16/2009 11:28:00 12:26:00 >> 28 40609 4 04/06/2009 11:17:00 >> 53 42709 4 04/27/2009 11:15:00 9:30:00 >> 76 51109 3 05/11/2009 11:51:00 >> 101 51809 1 05/18/2009 12:28:00 >> 126 62209 3 06/22/2009 11:31:00 >> 150 71309 4 07/13/2009 12:12:00 13:37:00 >> 173 81009 4 08/10/2009 11:32:00 20:52:00 >> Start_of_Experiment >> 1 2009-02-02 12:38:00 >> 26 2009-03-02 12:40:00 >> 27 2009-03-16 11:28:00 >> 28 2009-04-06 11:17:00 >> 53 2009-04-27 11:15:00 >> 76 2009-05-11 11:51:00 >> 101 2009-05-18 12:28:00 >> 126 2009-06-22 11:31:00 >> 150 2009-07-13 12:12:00 >> 173 2009-08-10 11:32:00 >> >> [[alternative HTML version deleted]] >> >> ______________________________**________________ >> R-help@r-project.org mailing list >> https://stat.ethz.ch/mailman/**listinfo/r-help<https://stat.ethz.ch/mailman/listinfo/r-help> >> PLEASE do read the posting guide http://www.R-project.org/** >> posting-guide.html <http://www.R-project.org/posting-guide.html> >> and provide commented, minimal, self-contained, reproducible code. >> > > [[alternative HTML version deleted]] ______________________________________________ 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.
