Dear list, dear Henrik, I find myself often reconstructing matrices from the result of rowSum (matrix) etc. I therefore propose a new argument, drop, for these functions: drop = TRUE (default) is the current behaviour. With drop = FALSE length (dim (x)) and dimnames are preserved and the affected dimensions are set to 1 (or whatever teh result length of the applied function is) I modified the base functions in colSums.R accordingly, and provide the respective methods (I did not yet have the time to look into apply.R). I'm wondering whether these changes are of sufficient interest to the R public that these methods should have a more obvious "home" than a spectroscopy package. As I learned this morning of package matrixStats: Henrik, would you like to include these modified functions? Anyways, the code is in the attached file, so if someone needs the funcionality, he can find it here. Claudia -- Claudia Beleites Dipartimento dei Materiali e delle Risorse Naturali Universit? degli Studi di Trieste Via Alfonso Valerio 6/a I-34127 Trieste phone: +39 0 40 5 58-37 68 email: cbeleites at units.it -------------- next part -------------- An embedded and charset-unspecified text was scrubbed... Name: colSums.R URL: <https://stat.ethz.ch/pipermail/r-devel/attachments/20110214/d4641f70/attachment.pl>