Dear R-list, I am having troubles selecting rows from a very large data-set containing distances between capitals.
The structure of the data-set looks like this: numa ida numb idb kmdist midist 1 2 USA 20 CAN 731 456 2 2 USA 31 BHM 1623 1012 3 2 USA 40 CUB 1813 1130 I want to select a subset of these dyads, and have tried the following code: subset(capdist,ida == c("DEN","SWD","FIN") & idb == c("DEN","SWD","FIN")) This should ideally give me the dyads involving only Denmark, Sweden and Finland, however i get the error message: [1] numa ida numb idb kmdist midist <0 rows> (or 0-length row.names) Warning messages: 1: In is.na(e1) | is.na(e2) : longer object length is not a multiple of shorter object length 2: In `==.default`(ida, c("DEN", "SWD", "FIN")) : longer object length is not a multiple of shorter object length 3: In is.na(e1) | is.na(e2) : longer object length is not a multiple of shorter object length 4: In `==.default`(idb, c("DEN", "SWD", "FIN")) : longer object length is not a multiple of shorter object length Any help would be greatly appreciated, Best, Thomas Jensen [[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.