Since both sequences are in hourly steps, there is a fairly easy way to do this:
> before <- colSums(outer(seq1, seq2, "<")) > sort(c(seq1[before], seq1[before+1])) This uses the fact that both sequences are in hourly time steps, so the time stamp 'just after' the member of seq2 is the next one to the one 'just before'. Relaxing this assumption, if needed, is left as an easy exercise. Bill Venables -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Lauri Nikkinen Sent: Thursday, 21 February 2008 5:04 PM To: [EMAIL PROTECTED] Subject: [R] Selecting timestamps R-users, I have two vectors (of timestamps) d1 <- as.POSIXct(strptime("2.2.2002 07:00", format="%d.%m.%Y %H:%M")) d2 <- as.POSIXct(strptime("4.2.2002 07:00", format="%d.%m.%Y %H:%M")) seq1 <- seq(d1, d2, "hours") seq1 d3 <- as.POSIXct(strptime("2.2.2002 15:22", format="%d.%m.%Y %H:%M")) d4 <- as.POSIXct(strptime("3.2.2002 18:12", format="%d.%m.%Y %H:%M")) seq2 <- seq(d3, d4, "hours") seq2 How to select timestamps from seq1 which are just before and after of particular timestamp in seq2? The resulting vector should look like this in this example: "2002-02-02 15:00:00 Normaaliaika" "2002-02-02 16:00:00 Normaaliaika" "2002-02-02 16:00:00 Normaaliaika" "2002-02-02 17:00:00 Normaaliaika" "2002-02-02 17:00:00 Normaaliaika" "2002-02-02 18:00:00 Normaaliaika" "2002-02-02 18:00:00 Normaaliaika" etc. Thank you, Lauri > sessionInfo() R version 2.6.0 (2007-10-03) i386-pc-mingw32 locale: LC_COLLATE=Finnish_Finland.1252;LC_CTYPE=Finnish_Finland.1252;LC_MONETAR Y=Finnish_Finland.1252;LC_NUMERIC=C;LC_TIME=Finnish_Finland.1252 attached base packages: [1] stats graphics grDevices utils datasets methods base other attached packages: [1] RODBC_1.2-3 loaded via a namespace (and not attached): [1] tools_2.6.0 ______________________________________________ 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.
