On 10 Jan 2003 at 15:19, Tord Snall wrote: > Dear all, > > I would be really happy for help with the following because I will treat > many columns the same way. > > nlevels per ObjektID is what I want, but nlevels returns all levels > occurring in cpy.busk$TradArt: > > buskartant<- aggregate(list(trash = cpy.busk$TradArt), list(ObjektID = > cpy.busk$ObjektID), nlevels) > > But as you can see I use it below anyway. I could use any function instaed > of nlevels beacuse now I just want the ObjektID in the right order. > > Greg Warnes kindly helped me with this solution: > group.list <- split(cpy.busk$TradArt, cpy.busk$ObjektID) > buskartant$buskartant <- sapply( group.list, function(x) length(unique(x)) ) > > But the probelm is that unique considers NA as a category, and there is no > na.rm argument in unique().
What about wrapping unique in na.omit: na.omit(unique(x)) Kjetil Halvorsen > > Please give a hint. > > Thanks a lot in advance! > > Sincerely, > Tord > > ----------------------------------------------------------------------- > Tord Sn�ll > Avd. f v�xtekologi, Evolutionsbiologiskt centrum, Uppsala universitet > Dept. of Plant Ecology, Evolutionary Biology Centre, Uppsala University > Villav�gen 14 > SE-752 36 Uppsala, Sweden > Tel: 018-471 28 82 (int +46 18 471 28 82) (work) > Tel: 018-25 71 33 (int +46 18 25 71 33) (home) > Fax: 018-55 34 19 (int +46 18 55 34 19) (work) > E-mail: [EMAIL PROTECTED] > Check this: http://www.vaxtbio.uu.se/resfold/snall.htm! > ------------------------------------------------------------------------ > > ______________________________________________ > [EMAIL PROTECTED] mailing list > http://www.stat.math.ethz.ch/mailman/listinfo/r-help ______________________________________________ [EMAIL PROTECTED] mailing list http://www.stat.math.ethz.ch/mailman/listinfo/r-help
