How should R deal with matrices that have a 'names' attribute? S (and S+) did not allow an object to have both dims and names but R does. However, some R functions copy the dims but not the names to the returned value and some copy both. I don't see a pattern to it. Is there a general rule for when the names on a matrix should be copied to the return value of a function?
> x <- matrix(11,1,1) > names(x)<-"One" > dput(x) structure(11, .Dim = c(1L, 1L), .Names = "One") > dput(log2(x)) structure(3.4594316186373, .Dim = c(1L, 1L), .Names = "One") > dput(pchisq(x,8)) structure(0.798300801297471, .Dim = c(1L, 1L), .Names = "One") > dput(x+1) structure(12, .Dim = c(1L, 1L)) > dput(x > 3) structure(TRUE, .Dim = c(1L, 1L)) > dput(!x) structure(FALSE, .Names = "One", .Dim = c(1L, 1L)) > dput(-x) structure(-11, .Dim = c(1L, 1L), .Names = "One") > dput(0-x) structure(-11, .Dim = c(1L, 1L)) The binary operators don't copy, unary operators do copy, and many other low-level functions do copy. Bill Dunlap TIBCO Software wdunlap tibco.com [[alternative HTML version deleted]] ______________________________________________ R-devel@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-devel