Brian, Prof Brian Ripley <mailto:[EMAIL PROTECTED]> wrote: > This is one of those undocumented things (AFAIK): LENGTH applies only > to 'vectors'. So don't use t and definitely don't set it for others. > The macro expands to > > #define LENGTH(x) (((VECSEXP) (x))->vecsxp.length) > > What is a vector here? Something which gets actually allocated by > allocVector() AFAICS, that is an atomic or generic vector or an > expression. OTOH, an EXTPTRSXP is stored in a cons cell. > > There is also a function length(), which is safer.
Thanks for your message. Things are much clearer now to me. Can I safely assume that INTSXP, REALSXP, LGLSXP, STRSXP, CPLXSXP and VECSXP are vectors (while EXTPTRSXP is not). Thomas ______________________________________________ R-devel@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-devel
