A minor issue with data.frame is a change introduced leading to R 2.5.0, where row.names=NULL (i.e., do not name rows) is not honored with a named vector
> x <- letters[1:3] > names(x) <- x > data.frame(x, row.names=NULL) x a a b b c c and a slightly more subtle example > data.frame(y=1:3, x, row.names=NULL) y x a 1 a b 2 b c 3 c A 2.5.0 news entry says o data.frame() ignored 'row.names' for 0-column data frames, and no longer treats an explicit row.names=NULL differently from the default value. The relevant section of ?data.frame however says If 'row.names' was supplied as 'NULL' or no suitable component was found the row names are the integer sequence starting at one This is not consistent with the current behavior, and is unchanged from the pre 2.5.0 version. The workaround is distinctly hackish > df <- data.frame(x) > row.names(df) <- NULL > sessionInfo() R version 2.7.0 Under development (unstable) (2007-10-13 r43163) x86_64-unknown-linux-gnu Martin ______________________________________________ R-devel@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-devel