Hi Rui, thanks for the quick fix. I am still wrapping my mind around your expression, but unfortunately it doesn't quite give me what I want. You are calculating differences between the start times. However, I would like to know the 'idle' periods between the events, ie the time between the end of one event and the beginning of the next (but only for the events that start on the same day).
Best, Kai On Thu, May 9, 2013 at 1:55 PM, Rui Barradas <ruipbarra...@sapo.pt> wrote: > Hello, > > If I understand it well, try the following. > > > tmp <- lapply(tapply(as.POSIXct(**paste(df[,1], df[,2])), df[,1], diff), > `*`, 60) > lapply(tmp, as.integer) > > > Hope this helps, > > Rui Barradas > > Em 09-05-2013 11:45, Kai Mx escreveu: > >> Hi everybody, >> I have an analysis problem that seems a little overwhelming to me, but is >> probably not too hard to solve for you guys. I have a (fairly large) >> dataframe that indicates usage of a resource on different days: >> >> df <-data.frame ( >> dstartday =c(rep('2012-02-10', 4), rep('2012-02-11', 5)), >> dstart =c('08:05:00','09:35:00', '12:00:00','13:00:00', '07:50:00', >> '9:45:00', '13:00:00', '14:05:00', '15:50:00'), >> dendday =c (rep('2012-02-10', 3), '2012-02-11',rep('2012-02-12', 5)), >> dend = c ('08:35:00','09:40:00', '12:20:00', '01:00:00', '08:35:00', >> '11:00:00', '13:15:00', '15:00:00', '17:00:00') >> ) >> >> Each row reflects an event that starts at the date and time that is >> indicated by dstartday/dstart and ends at dendday/dend. >> Now I would like to calculate the time intervals in minutes between the >> different events that start on a specific day, eg for '2012-02-10' it >> should be 60, 140, 40. The interval between the last event of the day and >> the first event of the next is not relevant and should be ignored. Events >> may run overnight, but there should not be any overlaps between start and >> end times. >> I have imported all the data as strings. >> Any thoughts and suggested readings/packages are really appreciated, >> thanks! >> >> Best, >> >> Kai >> >> [[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.