How about this? value.vec[which.vec] HTH,
Jorge On Tue, Dec 23, 2008 at 9:52 PM, Sean Zhang <seane...@gmail.com> wrote: > Dear R-Helpers: > > I am a entry level user of R. > > Have the following question. Many thanks in advance. > > > # value.vec stores values > value.vec <- c('a','b','c') > # which.vec stores the locations/indexs of values in value.vec. > which.vec <- c(3, 2, 2, 1) > # How can I obtain the following vector based on the value.vec and > which.vec > mentioned above > # vector.I.want <- c('c', 'b', 'b', 'a') > # 3 2 2 1 > > > # I try to avoid using the following loop to achieve the goal because the > which.vec in reality will be very long > > vector.I.want <- rep(NA,length(which.vec)) > for (i in 1:length(which.vec)) > { vector.I.want[i] <- value.vec[which.vec[i]] } > > # is there a faster way than looping? > > Thanks in advance. > > -Sean > > [[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. > [[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.