If we assume the distance is linear, this might work: > x ID loc 1 1 144 2 2 144 3 3 140 4 4 126 5 5 120 6 6 112 7 7 100 8 8 99 9 9 91 10 11 90 11 12 90 12 13 89 13 15 86 14 16 85 15 17 85 16 18 80 17 19 79 18 20 79 19 21 78 20 22 78 21 23 76 22 24 74 23 25 73 24 26 72 25 27 71 26 28 68 27 29 68 28 30 68 > x.outer <- outer(x$loc, x$loc, function(a,b) abs(a - b)) > # set diag to Inf so a point is not closest to itself > diag(x.outer) <- Inf > # assume that you choose the 8th element, here are the closest IDs > x$ID[order(x.outer[,8])] [1] 7 9 11 12 13 6 15 16 17 18 19 20 5 21 22 23 24 25 4 26 27 28 29 30 3 1 2 8 > >
On Sun, Mar 22, 2009 at 2:04 PM, P_M <pmart...@broadpark.no> wrote: > > Yes, of course. > > ID loc > 1 144 > 2 144 > 3 140 > 4 126 > 5 120 > 6 112 > 7 100 > 8 99 > 9 91 > 11 90 > 12 90 > 13 89 > 15 86 > 16 85 > 17 85 > 18 80 > 19 79 > 20 79 > 21 78 > 22 78 > 23 76 > 24 74 > 25 73 > 26 72 > 27 71 > 28 68 > 29 68 > 30 68 > . . > . . > 185 -22 > > > P_M wrote: >> >> 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-tp22647126p22648754.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. > -- Jim Holtman Cincinnati, OH +1 513 646 9390 What is the problem that you are trying to solve? ______________________________________________ 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.
