Hi,
I have a dataframe SDF1 that looks like this: Char1 Char2 Char 3 W.2007.02 W.2007.09 W.2007.16 W.2008.13 A C1 F1 F2 F3 A C2 F4 B C3 F5 F6 I have another dataframe SDF2 with 163 cols that has the following column names Char1 Char2 Char 3 W.2007.02 W.2007.03 W.2007.04 W.2007.05 W.2007.06 .W.2007.52 W.2008.01 . W.2008.13 Now I would like to add the missing period names to SDF1 as new columns and in the same order as in SDF2. Therefore I use the following formula: [[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.