Hello! library(gsubfn) test <- c('filename_1_def.pdf', 'filename_2_abc.pdf') gsubfn("(.+_)([a-z]+)(\\.pdf)", "\\2", test)
Cheers!! Albert-Jan ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ All right, but apart from the sanitation, the medicine, education, wine, public order, irrigation, roads, a fresh water system, and public health, what have the Romans ever done for us? ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ >________________________________ >From: Jannis <bt_jan...@yahoo.de> >To: r-h...@stat.math.ethz.ch >Sent: Wednesday, October 5, 2011 1:56 PM >Subject: [R] help with regexp > >Dear list memebers, > > >I am stuck with using regular expressions. > > >Imagine I have a vector of character strings like: > >test <- c('filename_1_def.pdf', 'filename_2_abc.pdf') > >How could I use regexpressions to extract only the 'def'/'abc' parts of these >strings? > > >Some try from my side yielded no results: > >testresults <- grep('(?<=filename_[[:digit:]]_).{1,3}(?=.pdf)', perl = TRUE, >value = TRUE) > >Somehow I seem to miss some important concept here. Until now I always used >nested sub expressions like: > >testresults <- sub('.pdf$', '', sub('^filename_[[:digit:]]_', '' , test)) > > >but this tends to become cumbersome and I was wondering whether there is a >more elegant way to do this? > > > >Thanks for any help > >Jannis > > > >______________________________________________ >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. > > > [[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.