Hi! I don't really understand your goal, but if you want to extract the row names, rownames(a[which(a[,3] < 8), ]) does it.
But I think you've already tried it. Maybe it's just me... HTH Ivan Le 9/3/2010 15:08, syrvn a écrit : > Hi, > > the R code: > > a<- matrix(c(1,5,4,3,7,10,34,4,3,8,6,5,12,17,45,3,2,45,46,47,3,4,22,12,21), > nrow=5) > rownames(a)<- c("a","b","c","d","e") > a > a[which(a[,3]< 8), ] > a[which(a[,3]< 6), ] > > > produces the following output: > >> a > [,1] [,2] [,3] [,4] [,5] > a 1 10 6 3 3 > b 5 34 5 2 4 > c 4 4 12 45 22 > d 3 3 17 46 12 > e 7 8 45 47 21 > >> a[which(a[,3]< 8), ] > [,1] [,2] [,3] [,4] [,5] > a 1 10 6 3 3 > b 5 34 5 2 4 > >> a[which(a[,3]< 6), ] > [1] 5 34 5 2 4 > > > I actually thought it must be rather easy to somehow extract the row name > when the result is just a vector as in the second example and not a matrix. > I tried several ways but without any success. > > Any advice? > Best, > syrvn > > -- Ivan CALANDRA PhD Student University of Hamburg Biozentrum Grindel und Zoologisches Museum Abt. Säugetiere Martin-Luther-King-Platz 3 D-20146 Hamburg, GERMANY +49(0)40 42838 6231 ivan.calan...@uni-hamburg.de ********** http://www.for771.uni-bonn.de http://webapp5.rrz.uni-hamburg.de/mammals/eng/mitarbeiter.php [[alternative HTML version deleted]]
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