?? On Mon, Jul 30, 2012 at 11:46 AM, R. Michael Weylandt <michael.weyla...@gmail.com> wrote: > On Mon, Jul 30, 2012 at 8:49 AM, Bert Gunter <gunter.ber...@gene.com> wrote: >> Not necessarily. If the OP really meant the R list() structure, then >> is.element does not apply. > > Perhaps... > > x <- list(1:5, "a", `+`, rnorm, NULL, list(letters))
Note: > is.element((1:5),x) [1] FALSE FALSE FALSE FALSE FALSE ##The answer should be TRUE -- the vector (1:5) is a list component. Similarly: > is.element(letters,x) [1] TRUE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE [13] FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE [25] FALSE FALSE ## The answer again should be TRUE. > is.element(rnorm,x) Error in match(el, set, 0L) : 'match' requires vector arguments ## The answer should be TRUE. So I do not understand what your point is. I stand by my claim: is.element is not intended for lists, and this is made clear (to me, anyway) in the help file. -- Bert > > letters %in% x # Works -- vectorized, mostly false, but the "a" is > there, per below > "a" %in% x # Works, true > > 1 %in% x # Works, false > 1:5 %in% x # Works -- vectorized, false > list(1:5) %in% x # Works, true > > `+` %in% x # Error > NULL %in% x # logical(0) > > so it seems is.element / %in% [chacun son gout] works with "vectors" > (in a rather broad sense of that word) > > I'm still trying to understand quite how this one works though: > > list(letters) %in% x # Works -- false: this one surprised me! > identical(list(letters), x[[6]]) # True > > Best, > Michael -- Bert Gunter Genentech Nonclinical Biostatistics Internal Contact Info: Phone: 467-7374 Website: http://pharmadevelopment.roche.com/index/pdb/pdb-functional-groups/pdb-biostatistics/pdb-ncb-home.htm ______________________________________________ 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.
