In addition to Mike's comment: > x<-c(0.1,0.9) > 1-x[2] [1] 0.1 > x[1]==1-x[2] [1] FALSE > all.equal(x[1], 1-x[2]) [1] TRUE
b On Jan 26, 2007, at 11:40 AM, Mike Prager wrote: > Not at all strange, an expected property of floating-point > arithmetic and one of the most frequently asked questions here. > >> print(0.1, digits=17) > [1] 0.1 >> print(1 - 0.9, digits=17) > [1] 0.09999999999999998 >> > > A simple description of the issue is at > > http://docs.python.org/tut/node16.html > > In most cases, it suffices to test for approximate difference or > relative difference. The former would look like this > > if (abs(x[1] - x[2]) < eps)) ... > > with "eps" set to something you think is an insignificant > difference, say 1.0e-10. > > > -- > Mike Prager, NOAA, Beaufort, NC > * Opinions expressed are personal and not represented otherwise. > * Any use of tradenames does not constitute a NOAA endorsement. > > ______________________________________________ > R-help@stat.math.ethz.ch 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. ______________________________________________ R-help@stat.math.ethz.ch 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.