Hi r-help-boun...@r-project.org napsal dne 02.07.2009 12:40:05:
> I have a data frame (hf) that is all set up and the dates are working > fine - however I need to extract the months and hours (2 separate > columns) as numbers - however they are coming out as characters. > > I have tried both the following: > > hf50$hour= hf50$date > hf50$hour=format(hf50["hour"],"%H") > > and > > hf$month <- as.POSIXct(strptime(hf$date, format = "%m")) If hf$date is in POSIX format then format(hf$date,"%m") shall give you month as a number 01-12. Actually it is a character and you need to convert it to numbers by as.numeric. If it is in different format then depending on how it is actually formatted you can use strptime to transform it to POSIX class and then to use format to extract only days or months from it. Regards Petr > > but they are still coming out as characters. > > Any ideas please? > Thanks, > Tim. > > ______________________________________________ > 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.
