Hi-- I suspect this is a frequently considered (and possibly asked) question, but I haven't thus far found an answer:
For slicing a vector with x[…], is there a symbol for length(x)? I'm seeking a short-hand for referring to the length of vector one is trying to index. E.g., for a data.frame, say, > test.frame <-data.frame(matrix(c(1:100),ncol=10,nrow=10,byrow=T)) > names(test.frame) <- names(islands)[1:10] is there a short-hand for subsetting > test.frame$Baffin[1:(length(test.frame$Baffin)-3)] [1] 6 16 26 36 46 56 66 > > that would allow one to avoid the "(length(some.dataframe$variable)-offset)"? I was thinking something paralleling the use of negative indices in […] might exist with seq(from,to), e.g. for the above > test.frame$Baffin[seq(,7)] [1] 6 16 26 36 46 56 66 > works. But the fantasy test.frame$Baffin[seq(,-3)] obviously doesn't… Any suggestions will be gratefully appreciated… As always, many thanks to the patient list members who helps on these simple questions... Best, Eric -- Eric Rupley University of Michigan, Museum of Anthropology 1109 Geddes Ave, Rm. 4013 Ann Arbor, MI 48109-1079 erup...@umich.edu +1.734.276.8572 ______________________________________________ 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.