Peter Dalgaard wrote: > Wacek Kusnierczyk wrote: > >> m = matrix(1:4, 2) >> >> apply(m, 1, cat, '\n') >> # 1 2 >> # 3 4 >> # NULL >> >> why the null? >> > > It comes from unlist()ing a list of NULLs, which in turn are the return > values of cat(). >
yes; i'd think i'd get a list of nulls, but... > It is arguably a design-buglet not to return list(NULL, NULL), but the > internal logic is to unlist() unless the first element is.recursive (and > NULL is not) or the return values have different length() (and all are > zero). It _is_, however, in accordance with the documentation (see the > Value: section): > ... i agree the actual outcome is appropriately explained in the docs. i don't think it has no merit, but it's a bit surprising at first. thanks, vQ ______________________________________________ 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.
