Charles C. Berry <cberry <at> tajo.ucsd.edu> writes: > > On Mon, 5 Jul 2010, Moohwan Kim wrote: > > > Dear R family, > > > > I have a question about how to detect some duplicate numeric observations. > > Suppose that I have two variables dataset. > > > > order value > > 1 0.52 > > 2 0.23 > > 3 0.43 > > 4 0.21 > > 5 0.32 > > 6 0.32 > > 7 0.32 > > 8 0.32 > > 9 0.32 > > 10 0.12 > > 11 0.46 > > 12 0.09 > > 13 0.32 > > 14 0.25 > > ; > > Could you help me indicate where the duplicate observations in a row > > (e.g., 0.32) are? > > I see you already have replies about duplicate() and unique(), which are > very handy for the 'detect' part of your query. > > But to list the locations of the duplciated elements, you might also > benefit from using split() and Filter() like this: > > > Filter( function(x) length(x)>1, split(order, value) ) > $`0.32` > [1] 5 6 7 8 9 13 >
Mark Leeds kindly pointed out (in private correspondence) that this needs a bit more explanation. If the above 'dataset' is in fact a data.frame called 'dat' then either attach(dat) Filter( function(x) length(x)>1, split(order, value) ) or Filter( function(x) length(x)>1, split(dat$order, dat$value) ) or with( dat, Filter( function(x) length(x)>1, split(order, value) ) ) should do it. Thanks Mark! [snip] ______________________________________________ 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.
