Hi, Does this work for you? It simply tests if the name Fisher is found among the names of the elements of spec.
obj = list(spec = list) Fisher <- ifelse(!("Fisher" %in% names(obj$spec)), FALSE, obj$spec$Fisher) Cheers, Ben On Dec 14, 2014, at 8:07 AM, Steven Yen <sye...@gmail.com> wrote: > My obj does not always come with a logical variable defined. So I do > > my.foo <- function(obj,df,digits=5){ > if (!is.na("obj$spec$Fisher")) Fisher<-obj$spec$Fisher > ... > } > > This works when "Fisher" is defined in/passed from obj. When it is not, I get > error: > > Error in (!is.na("obj$spec$Fisher")) & Fisher : > operations are possible only for numeric, logical or complex types > > I tried exist(Fisher), missing(Fisher)... to no vail. Any idea? Thanks. > > ______________________________________________ > R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see > 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. Ben Tupper Bigelow Laboratory for Ocean Sciences 60 Bigelow Drive, P.O. Box 380 East Boothbay, Maine 04544 http://www.bigelow.org ______________________________________________ R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see 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.