Hey Sara, first: Thanks for the fast reply! I checked the apply function and I found my error. For sure: I forgot to send an sample data. After sending the mail I recognized it. Sorry about this! Once again: Thanks for the fast reply and your help. Best Peter
Am 16.11.2012 um 15:26 schrieb Sarah Goslee <sarah.gos...@gmail.com>: > Hi Peter, > > On Fri, Nov 16, 2012 at 9:04 AM, Peter Kupfer <peter.kup...@me.com> wrote: >> Dear all, >> maybe a simple problem but I found no solution for my problem. >> I have a matrix Y with 23 000 rows and 220 colums. The entries are "A", "B" >> or "C". > > A reproducible example with sample data is helpful. > >> I want to extract all rows (as a matrix ) of the matrix Y where all entries >> of a row are (for example) "A". > > Really? Why not just make a new matrix with the right number of "A" values? > >> Is there any solution? I tried the stringr- package but i doesn't work out. > > Of course there is. Here's one option. But I'm not sure you've really > stated your actual problem. This extracts the rows where all values > are "A", and might at least get you started toward your real problem. > > testdata <- matrix(c( > "A", "B", "C", > "B", "B", "B", > "C", "A", "A", > "A", "A", "A"), > ncol=3, byrow=TRUE) > > testdata.A <- testdata[apply(testdata, 1, function(x)all(x == "A")), , > drop=FALSE] > > > > -- > 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.
