You don't need a loop for this, I think. Since you don't provide an example it's hard to know how your data are set up, but look at this:
> FULLSAMP <- data.frame(A = 1:10, B=letters[1:10]) > TESTSAMP <- data.frame(A = c(2,4,5,8), C=1:4) > FULLSAMP A B 1 1 a 2 2 b 3 3 c 4 4 d 5 5 e 6 6 f 7 7 g 8 8 h 9 9 i 10 10 j > TESTSAMP A C 1 2 1 2 4 2 3 5 3 4 8 4 > FULLSAMP[FULLSAMP$A %in% TESTSAMP$A,] A B 2 2 b 4 4 d 5 5 e 8 8 h Sarah On Thu, May 13, 2010 at 10:49 AM, Amit Patel <amitrh...@yahoo.co.uk> wrote: > Hi > > I have tried many attempts but cant get the loop right, as I am not a strong > programmer. What I am basically trying to do is compare 2 spreadsheets. The > problem is that one of them only contain a portion of the overall data > (TESTSAMP), where the other has a full datasetFULLSAMP. From the complete set > I would like to remove the rows of data which are not in the TESTSAMP. Column > 1 contains the sample numbers which can be used to identify samples. Does > anyone have any suggestions? > > I have tried various things like double loops and so on, but I am sure there > is an easier way or function to do this. > > i tried this method, but Im not sure how to only keep looping until a match > is found. I dont understand how repeat loops work in R. > > for (i in 1:length(FULLSAMP[,1])) { > > if (FULLSAMP[i,1] != TESTSAMP[i,1]) { > FULLSAMP <- FULLSAMP[-i,] > } > > > Thanks in advance > > > -- Sarah Goslee http://www.functionaldiversity.org ______________________________________________ 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.