Hi, The answer to your question is written on the help page.
?sort HTH, Pascal On 11/03/13 10:24, Jie wrote:
Dear All, Suppose I have a vector X = (x_1, x_2, ...., x_n), X_sort = sort(X) = (x_(1), x_(2), ... , x(n) ), and I would like to know the original position of these ordered x_(i) in X, how can I do it? case 1: all values are unique x <- c( 3, 5, 4, 6) x.sort <- sort(x) # # I would like to obtain a vector (1, 3, 2, 4) which indicates that 3 in x is still the 1st element in x.sort, 5 is at the 3rd position in x.sort. etc. case 2: some x_i's have the same value x <- c(3, 3, 5, 5, 4, 4, 6, 6) I would like to obtain a vector as (1, 2, 5, 6, 3, 4, 7, 8) I do not want to use which and loop over the vector to do it since for a long vector it is not fast enough. Thank you for your suggestion. Best wishes, Jie ______________________________________________ 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.
