Here is one way you might find useful > id <- 1:183 > lo <- sample((-22):144, 183, rep = TRUE) > ds <- outer(lo, lo, function(x,y) abs(x-y)) > rs <- t(apply(ds, 2, function(x) id[order(x)][2:11])) > rownames(rs) <- id
Here's what I got > head(rs) [,1] [,2] [,3] [,4] [,5] [,6] [,7] [,8] [,9] [,10] 1 118 23 125 182 183 8 86 119 141 175 2 27 167 176 4 126 45 113 81 144 153 3 43 7 18 60 148 11 12 150 85 163 4 126 27 167 176 2 45 144 153 48 55 5 15 46 86 141 175 23 125 183 1 118 6 58 78 139 13 66 131 156 181 117 157 If you want anything more random in the case of ties than this, you will have to work a bit harder on the code. W. Bill Venables http://www.cmis.csiro.au/bill.venables/ -----Original Message----- From: r-help-boun...@r-project.org [mailto:r-help-boun...@r-project.org] On Behalf Of P_M Sent: Monday, 23 March 2009 1:32 AM To: r-help@r-project.org Subject: [R] Selecting closest values Hi I have a table with ID (1 to 183) and Location (144 to -22). My problem is that I want to select the 10 ID's that are closest in Location to ID 1, ID 2 and so on. Also, some ID have the same Location. Say, if 11 ID's are closest to ID 100 I want to randomly choose one of the ID's to select 10 ID's total. Thank you -- View this message in context: http://www.nabble.com/Selecting-closest-values-tp22647126p22647126.html Sent from the R help mailing list archive at Nabble.com. ______________________________________________ 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.
