I assumed (since you did not provide reproducible code) that 'mag' was a matrix. If 'station' is a matrix, then
mag + rowSums(station) will work. If that does not work, then you need to tell us what your data objects are. On Sat, Sep 26, 2009 at 11:39 AM, tzygmund mcfarlane <tzygm...@googlemail.com> wrote: > Hi Jim, > > I might be missing something but your command gives the error: > Error in rowSums(mag) : 'x' must be an array of at least two dimensions > > ############################# > data(attenu) > attach(attenu) > rowSums(mag) + rowSums(station) > attenu$new<-rowSums(cbind(mag, station)) > ############################# > > Thanks > > > On Sat, Sep 26, 2009 at 4:30 PM, jim holtman <jholt...@gmail.com> wrote: >> Probably more efficient if you remove the 'cbind' which would create a >> combined matrix. Use the following: >> >> rowSums(mag) + rowSums(station) >> >> On Sat, Sep 26, 2009 at 11:16 AM, tzygmund mcfarlane >> <tzygm...@googlemail.com> wrote: >>> Hi, >>> >>> For very large matrices, is this the most efficient way to add two >>> variables together? >>> >>> ############################# >>> attach(attenu) >>> new<-rowSums(cbind(mag, station)) >>> ############################# >>> >>> Also, could I be directed to some resources for working with very >>> large datasets? >>> >>> Thanks >>> >>> ______________________________________________ >>> 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. >>> >> >> >> >> -- >> Jim Holtman >> Cincinnati, OH >> +1 513 646 9390 >> >> What is the problem that you are trying to solve? >> > -- Jim Holtman Cincinnati, OH +1 513 646 9390 What is the problem that you are trying to solve? ______________________________________________ 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.
