On Sep 8, 2011, at 2:42 PM, David Winsemius wrote: > > On Sep 8, 2011, at 3:35 PM, Alexander Engelhardt wrote: > >> Am 08.09.2011 20:48, schrieb Marc Schwartz: >> > There was a post from Martin Maechler some years ago and I had to search a >> > bit to find it. For these sorts of issues, I typically trust his judgement. >> > >> > The post is here: >> > >> > https://stat.ethz.ch/pipermail/r-help/2003-April/032471.html >> > >> > His solution also handles complex numbers. >> >> For those too lazy to follow >> He is basically creating the function is.whole: >> >> is.whole <- function(x) >> is.numeric(x) && floor(x)==x > > Are you sure? I thought the test would have been all.equal(x, round(x,0) ) > > My reasoning was that 1.999999999999 should be considered 2 but floor would > make it 1.
David, I am confuzzled. Why would that be equal to 2? > x == 2 [1] FALSE > 2 - x [1] 1.000089e-12 # The default tolerance is .Machine$double.eps ^ 0.5 > all.equal(x, 2, tol = .Machine$double.eps) [1] "Mean relative difference: 5.000445e-13" > all.equal(x, 2, tol = .Machine$double.eps ^ 0.5) [1] TRUE > > > x=1.999999999999 > > x > [1] 2 > print(x, 15) [1] 1.999999999999 > > floor(x) > [1] 1 > > isTRUE(all.equal(x, floor(x))) > [1] FALSE > > all.equal(x, round(x,0)) > [1] TRUE > > >> >> Seems like the most appropriate way now. I'll make it so! Very apropos on the 45th anniversary of Star Trek. :-) >> Thanks for your help :-) >> -- Alex Cheers, Marc ______________________________________________ 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.
