Adrian, Yes, any "whole" number coming out of a computation bitten by floating point issues, I think.
> x = 1/49*49 > x [1] 1 > x%%1 [1] 1 > is.wholenumber <- + function(x, tol = .Machine$double.eps^0.5) abs(x - round(x)) < tol > is.wholenumber(x) [1] TRUE Best, ~G P.S Credit to Hadley Wickham for recently pointing out on twitter that 49 is the first number like this. I would have had to have gone searching for one otherwise. On Thu, Dec 17, 2015 at 7:02 AM, Adrian Dușa <dusa.adr...@unibuc.ro> wrote: > In the help page for ?is.integer, there is this function > > is.wholenumber <- > function(x, tol = .Machine$double.eps^0.5) abs(x - round(x)) < tol > > A quick question: is there a case where this alternative function will not > work? > function(x) x %% 1 == 0 > > Best, > Adrian > > -- > Adrian Dusa > University of Bucharest > Romanian Social Data Archive > Soseaua Panduri nr.90 > 050663 Bucharest sector 5 > Romania > > [[alternative HTML version deleted]] > > ______________________________________________ > R-devel@r-project.org mailing list > https://stat.ethz.ch/mailman/listinfo/r-devel > -- Gabriel Becker, PhD Associate Scientist (Bioinformatics) Genentech Research [[alternative HTML version deleted]] ______________________________________________ R-devel@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-devel
