[R] wildcards and removing variables

[Marc Schwartz (via MN)]

On Mon, 2005-10-10 at 16:01 +0100, Prof Brian Ripley wrote:
> On Mon, 10 Oct 2005, Marc Schwartz (via MN) wrote:
> 
> > On Mon, 2005-10-10 at 10:37 -0400, Afshartous, David wrote:
> >> 	All,
> >>
> >> 	Is there are a wildcard in R for varible names as in unix?  For example,
> >>
> >> 	rm(results*)
> >>
> >> 	to remove all variable or function names that begin w/ "results"?
> >>
> >> 	cheers,
> >> 	Dave
> >> 	ps - please respond directly to afshar at miami.edu
> >
> >
> > See ?ls, which has a 'pattern' argument, enabling the use of Regex to
> > define the objects to be listed and subsequently removed using rm().
> >
> > You can then use something like:
> >
> >  rm(list = ls(pattern = "\\bresults."))
> 
> One new feature of R-2.2.0 is glob2rx, which converts wildcards to regexps 
> for you. E.g.
> 
> rm(list = ls(pattern = glob2rc("results*")))
> 
> (I think if does it a little better, as that trailing dot is not I think 
> correct: result* matches result.)

Thanks to both Gabor and Prof. Ripley for pointing out the use of
glob2rc(). One of the new features I had forgotten about since reading
NEWS.

On the trailing dot, I was just in the process of drafting a follow up
after realizing my error, since as you point out, 'results' would not be
matched in that case.

Thanks,

Marc