Joel Kincaid wrote: > > R-Community, > > I'm puzzled by the following behavior in R 1.6.2 and have found no > reference to this in the archives: > > >P <- seq(.1,.9,by=.1) > > >P[P > .4] > [1] 0.5 0.6 0.7 0.8 0.9 > as expected. However, > >P[P > .3] > [1] 0.3 0.4 0.5 0.6 0.7 0.8 0.9 > ??? > Which is unexpected. Furthermore on the logical side > > P>.1 > [1] FALSE TRUE TRUE TRUE TRUE TRUE TRUE TRUE TRUE > > P>.2 > [1] FALSE FALSE TRUE TRUE TRUE TRUE TRUE TRUE TRUE > > P>.3 > [1] FALSE FALSE TRUE TRUE TRUE TRUE TRUE TRUE TRUE > > P>.4 > [1] FALSE FALSE FALSE FALSE TRUE TRUE TRUE TRUE TRUE > > P>.5 > [1] FALSE FALSE FALSE FALSE FALSE TRUE TRUE TRUE TRUE > > P>.6 > [1] FALSE FALSE FALSE FALSE FALSE FALSE TRUE TRUE TRUE > > P>.7 > [1] FALSE FALSE FALSE FALSE FALSE FALSE TRUE TRUE TRUE > > What's with .3 and .7? Any pointers to where I might find out the info > would be greatly appreciated, > > I'm running 1.6.2 on windows XP, > Sincerely, > > Joel F. Kincaid, Ph. D. > Assistant Professor > Department of Economics and Finance > Franklin P. Perdue School of Business > Salisbury University > Salisbury Maryland, 21801 > Phone: (410) 548-4416 > Email: [EMAIL PROTECTED] > > ______________________________________________ > [EMAIL PROTECTED] mailing list > https://www.stat.math.ethz.ch/mailman/listinfo/r-help
a) It has nothing to do with indexing. b) It not completely unexpected. In seq() some computations are involved, hence it's just a very small inaccuracy which is expected when working with limited machines such as computers: options(digits=22) # some more details ... seq(.1, .9, .1) # Ah, that's it! ;-) Uwe Ligges ______________________________________________ [EMAIL PROTECTED] mailing list https://www.stat.math.ethz.ch/mailman/listinfo/r-help
