See ?get and ?do.call. That should be enough. ?Reduce may be an alternative for do.call(), but could also be less memory efficient.
My $.02 /Henrik On Thu, Jun 9, 2011 at 7:57 PM, Ben Zaitchik <zaitc...@jhu.edu> wrote: > Hello, > > I have a large number of raster objects in memory, with names RH100, RH101, > RH102, etc. (myobjects <- ls(pattern='^RH')). > These rasters are sections of a continuous map, and I would like to combine > them using the RasterObject merge tool in package 'raster.' > > Merge expects an input list of raster objects (outmap<-merge(x, y, ...), > where x, y, and ... are raster objects). I can run the command successfully > if I type in every raster object that I want to merge, but this is > impractical for the large number of objects I'm combining. > > I would like to apply merge to a list of object names defined using some > kind of wildcard-based list command, but I'm struggling to find the right > data types in R. > > Is there some way to convert a vector of strings (e.g., > as.vector(ls(pattern='^RH'))) to a vector of object names (as.names??) that > could be specified as the input to the merge function? What I'd really like > to do is something like outmap<-merge(myobjects[1:40]), in order to merge > the 40 raster objects, but I recognize that it might not be so simple. > > Advance apologies if this is already dealt with on the help list . . . I've > gone in circles on wildcard, lapply, and names threads and haven't managed > to get anything to work. > > Thank you, > Ben > > ______________________________________________ > 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. > ______________________________________________ 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.
