match(b, a) ? Michael
Right! Thanks, Michael.
On 16 September 2010 17:13, Niels Richard Hansen <niels.r.hansen+li...@math.ku.dk> wrote:> Dear R-help-list > > I have two character vectors > > a <- c("A", "B", "C") > b <- c("A", "C", "B") > > Then > > sapply(a, function(i) grep(i, b)) > > computes the permutation of the entries in 'b' needed > to bring 'b' into the same order as 'a'. > > I have searched around, but haven't been able to find > any existing function that compute this permutation. > Is there such a function doing this -- perhaps more > efficiently than the above? > > For those interested, I need the permutation to bring > the rows of a data frame into the same order as the > levels of a factor. > > Thanks, Niels >
-- Niels Richard Hansen Web: www.math.ku.dk/~richard Associate Professor Email: niels.r.han...@math.ku.dk Department of Mathematical Sciences nielsrichardhan...@gmail.com University of Copenhagen Skype: nielsrichardhansen.dk Universitetsparken 5 Phone: +45 353 20783 (office) 2100 Copenhagen Ø +45 2859 0765 (mobile) Denmark ______________________________________________ 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.
