> On 9 Oct 2017, at 17:02 , Duncan Murdoch <murdoch.dun...@gmail.com> wrote: > > I have a file containing "words" like > > > a > > a/b > > a/b/c > > where there may be multiple words on a line (separated by spaces). The a, b, > and c strings can contain non-space, non-slash characters. I'd like to use > gsub() to extract the c strings (which should be empty if there are none). > > A real example is > > "f 147/1315/587 2820/1320/587 3624/1321/587 1852/1322/587" > > which I'd like to transform to > > " 587 587 587 587" > > Another real example is > > "f 1067 28680 24462" > > which should transform to " ". > > I've tried a few different regexprs, but am unable to find a way to say > "transform words by deleting everything up to and including the 2nd slash" > when there might be zero, one or two slashes. Any suggestions? >
I think you might need something like this: s <- "f 147/1315/587 2820/1320/587 3624/1321/587 1852/1322/587" l <- strsplit(s, " ")[[1]] pat <- "[[:alnum:]]*/[[:alnum:]]*/([[:alnum:]]*)" paste(ifelse(grepl(pat,l),gsub(pat, "\\1", l), ""), collapse=" ") -pd > Duncan Murdoch > > ______________________________________________ > R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see > 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. -- Peter Dalgaard, Professor, Center for Statistics, Copenhagen Business School Solbjerg Plads 3, 2000 Frederiksberg, Denmark Phone: (+45)38153501 Office: A 4.23 Email: pd....@cbs.dk Priv: pda...@gmail.com ______________________________________________ R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see 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.
