Hi, I am trying to assign "Season" values to dates depending on when they occur.
For example, the following dates would be assigned the following "Season" numbers based on the "season" intervals detailed below in the code: ddate Season 29/12/1998 20:00:33 1 02/01/1999 05:20:44 2 02/01/1999 06:18:36 2 02/02/1999 07:06:59 3 02/03/1999 07:10:56 4 02/03/1999 07:57:18 4 My approach so far doesnt work because of the time stamps and is probably very long winded. However, to prevent errors I would prefer to keep the date formats as dd/mm/yyyy as oppose to a numeric format. Any help on the following code would be gratefully recieved: ddate <- c("29/12/1998 20:00:33", "02/01/1999 05:20:44", "02/01/1999 06:18:36", "02/02/1999 07:06:59", "02/03/1999 07:10:56", "02/03/1999 07:57:18") ddate <- as.POSIXct(strptime(ddate, "%d/%m/%Y %H:%M:%S"), "GMT") is.between<-function(x, a, b) { (x > a) & (b > x) } ddate$s1 <- is.between(ddate, 01/12/1998 00:00:00, 31/12/1998 23:59:59) ddate$s2 <- is.between(ddate, 01/01/1999 00:00:00, 31/01/1999 23:59:59) ddate$s3 <- is.between(ddate, 01/02/1999 00:00:00, 28/02/1999 23:59:59) ddate$s4 <- is.between(ddate, 01/03/1999 00:00:00, 31/03/1999 23:59:59) Many thanks -- View this message in context: http://r.789695.n4.nabble.com/find-date-between-two-other-dates-tp4639231.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.