On Thu, 2009-06-04 at 10:57 +0800, Ronggui Huang wrote: > 2009/6/4 Jason Rupert <jasonkrup...@yahoo.com>: <snip /> > > HouseDates <- c("02/27/90", "02/27/91", "01/14/92", "02/28/93", "02/01/94", > > "02/01/95", "02/01/96") > > > > # ?as.Date > > HouseDatesFormatted<-as.Date(HouseDates, "%m/%d/%y") > > > > HouseDatesFormatted > > > > HouseDatesList<-strsplit(as.character(HouseDatesFormatted), "-", fixed=TRUE) > > > sapply(HouseDatesList,function(x) x[[1]]) > [1] "1990" "1991" "1992" "1993" "1994" "1995" "1996"
Marc has provided a more direct way of achieving the result that the OP wanted, but as I often find myself writing sapply calls like Ronggui's, it is worth pointing out you can simplify such calls by dropping the anonymous function. In this case we can apply the `[[` function. '1' is an argument to this function, which sapply() allows us to pass on the sapply-ed function: > sapply(HouseDatesList, `[[`, 1) [1] "1990" "1991" "1992" "1993" "1994" "1995" "1996" For some reason, this idiom has been slow to catch on in my brain... G > > > > HouseYear_array<-NULL > > length_array<-length(HouseDatesList) > > for(ii in 1:length_array) > > { > > HouseYear<-HouseDatesList[[ii]][1] > > > > HouseYear_array<-c(HouseYear_array, HouseYear) > > } > > > > as.character(HouseYear_array) > > > > # Desired: > > # [1] "1990" "1991" "1992" "1993" "1994" "1995" "1996" > > > > ______________________________________________ > > 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. > > > > > -- %~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~% Dr. Gavin Simpson [t] +44 (0)20 7679 0522 ECRC, UCL Geography, [f] +44 (0)20 7679 0565 Pearson Building, [e] gavin.simpsonATNOSPAMucl.ac.uk Gower Street, London [w] http://www.ucl.ac.uk/~ucfagls/ UK. WC1E 6BT. [w] http://www.freshwaters.org.uk %~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~% ______________________________________________ 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.