Thanks again. By the way, any idea why I get this error:
merged3 <- merge_all(list_of_files , by = "Name") Error in `[.data.frame`(df, , match(names(dfs[[1]]), names(df))) : undefined columns selected > sessionInfo() R version 2.14.2 (2012-02-29) Platform: i386-pc-mingw32/i386 (32-bit) locale: [1] LC_COLLATE=English_Australia.1252 LC_CTYPE=English_Australia.1252 LC_MONETARY=English_Australia.1252 LC_NUMERIC=C LC_TIME=English_Australia.1252 attached base packages: [1] stats graphics grDevices utils datasets methods base other attached packages: [1] reshape_0.8.4 plyr_1.7.1 loaded via a namespace (and not attached): [1] tools_2.14.2 Cheers, Chintanu ============================================================================= On Wed, Apr 11, 2012 at 11:10 PM, R. Michael Weylandt < michael.weyla...@gmail.com> wrote: > Simply pass all = FALSE to merge_all > > merge_all(list_of_files, by = "Name", all = FALSE) > > Michael > > On Wed, Apr 11, 2012 at 1:09 AM, Chintanu <chint...@gmail.com> wrote: > > Thanks to David and Michael > > > > Michael: > > > > That works, however with a glitch. Each of my 24 files has got two > columns: > > "Name", and "Rank/score". > > > > file_list <- list.files() > > list_of_files <- lapply(file_list, read.csv) # Read in each file > > > > # I can see the 2-columns at this stage. However, the following line: > > > > merge_all(list_of_files, by = "Name") > > > > # produces some NAs for the 2nd column (except the beginning 1/3rd of the > > columns which have values). Not sure about the reason - the original > files > > don't have any NAs. > > > > > > Further, I understand that it gives the union of (rows of) files based on > > "Name". Is there a way to look for intersection, i.e., similar to using: > > merge (.... ,by="Name", all=FALSE) ? > > > > > > David: It came up with an error : > > > > do.call(merge, list_of_files, by="Name") > > > > Error in do.call(merge, list_of_files, by = "Name") : > > unused argument(s) (by = "Name") > > > > Cheers, > > Chintanu > > > > > [[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.