Consider the R code: mat <- matrix(seq(1,20),4,5) is.matrix(mat) # gives TRUE is.vector(mat) # gives FALSE
On the other hand, if mat is passed through the .Call interface the corresponding SEXP (call it smat) satisfies isMatrix(smat) // TRUE isVector(smat) // TRUE Consequently, you cannot distinguish matrices from vectors. Looking at the dim attribute of a vector doesn't help because this is garbage. Dominick ______________________________________________ R-devel@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-devel
