nrow is for number of rows in matrix/data.frame, here you can use: NROW(temp[1,]) length(temp[1,])
But if you want the index of row try this: unique(row(temp)[1,]) On 14/03/2008, Gregory Gentlemen <[EMAIL PROTECTED]> wrote: > Hi fellow R-users, > > I have run into a problem when trying to identify the number of rows in a > matrix. Say we have an arbitrary 5 by 5 matrix called temp: > > temp <- matrix(norm(25), nrow=5) > > The problem is that nrow(temp[1,]) returns NULL. I would like it to return 1 > because in my larger program I am indexing the rows of large matrices > according to another variable and I need to test when the resulting matrices > have 0, 1 or more rows. > > Thanks in advance for any assistance. > > Best regards, > Gregory Gentlemen > > > > > --------------------------------- > > [[alternative HTML version deleted]] > > ______________________________________________ > 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. > -- Henrique Dallazuanna Curitiba-Paraná-Brasil 25° 25' 40" S 49° 16' 22" O ______________________________________________ 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.
