Hi, I've read ?is.unsorted and searched. Have found a few items but nothing close, yet. Is the following expected?
> is.unsorted(data.frame(1:2)) [1] FALSE > is.unsorted(data.frame(2:1)) [1] FALSE > is.unsorted(data.frame(1:2,3:4)) [1] TRUE > is.unsorted(data.frame(2:1,4:3)) [1] TRUE IIUC, is.unsorted is intended for atomic vectors only (description of x in ?is.unsorted). Indeed the C source (src/main/sort.c) contains an error message "only atomic vectors can be tested to be sorted". So that is the error message I expected to see in all cases above, since I know that data.frame is not an atomic vector. But there is also this in ?is.unsorted: "except for atomic vectors and objects with a class (where the >= or > method is used)" which I don't understand. Where >= or > is used by what, and where? I understand why the first two are FALSE (1 item of anything must be sorted). I don't understand the 3rd and 4th cases where length is 2: do_isunsorted seems to call lang3(install(".gtn"), x, CADR(args))). Does that fall back to TRUE for some reason? Matthew > sessionInfo() R version 2.15.0 (2012-03-30) Platform: x86_64-pc-mingw32/x64 (64-bit) locale: [1] LC_COLLATE=English_United Kingdom.1252 LC_CTYPE=English_United Kingdom.1252 [3] LC_MONETARY=English_United Kingdom.1252 LC_NUMERIC=C [5] LC_TIME=English_United Kingdom.1252 attached base packages: [1] stats graphics grDevices utils datasets methods base other attached packages: [1] data.table_1.8.0 loaded via a namespace (and not attached): [1] tools_2.15.0 ______________________________________________ R-devel@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-devel