Dear r-devel members, It's just been brought to my attention that R permits non-unique column names in data frames -- e.g., via assignment to names() or colnames(). This behaviour is consistent with the help files (as I discovered), but it's not consistent with the behaviour of rownames() and row.names(). For example,
row.names(airquality) <- rep("a", nrow(airquality)) generates an error, but names(airquality) <- rep("a", ncol(airquality)) or even names(airquality) <- rep("", ncol(airquality)) do not. I figure that there must be some rationale for this difference, but I can't think of what it might be. Any thoughts? Regards, John -------------------------------- John Fox Department of Sociology McMaster University Hamilton, Ontario Canada L8S 4M4 905-525-9140x23604 http://socserv.mcmaster.ca/jfox ______________________________________________ R-devel@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-devel