Hi, It is because the column names do not exist. If you cast the matrix as a data frame your code would work. jon
-----Original Message----- From: r-help-boun...@r-project.org [mailto:r-help-boun...@r-project.org] On Behalf Of Lorenzo Cattarino Sent: 27. september 2010 10:27 To: r-help@r-project.org Subject: [R] name ONLY one column Hi R-users I can not change the name of one column only of my matrix. my_matrix <- matrix (1:12,ncol=3) colnames(my_matrix)[1] <- 'myname' Error in dimnames(x) <- dn : length of 'dimnames' [2] not equal to array extent thank you for your help Lorenzo [[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. ______________________________________________ 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.