As to the reasons, David as given you the necessary hints. In order to get around the issue, here is what I do:
> a <- round( 0.1 * ( 1:9 ), 1 ) > a [1] 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 > which( a == 0.3 ) [1] 3 Rgds, Rainer -------- Original-Nachricht -------- > Datum: Sun, 18 Mar 2012 21:43:54 +0000 > Von: Dajiang Liu <ldjst...@hotmail.com> > An: r-help@r-project.org > Betreff: [R] a very simple question > > Dear All, > I have a seemingly very simple question, but I just cannot figure out the > answer. I attempted to run the following:a=0.1*(1:9);which(a==0.3);it > returns integer(0). But obviously, the third element of a is equal to 0.3. > I must have missed something. Can someone kindly explain why? Thanks a > lot. > Regards,Dajiang > > [[alternative HTML version deleted]] > > ______________________________________________ > 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. -- ------- Gentoo Linux with KDE ______________________________________________ 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.