> > > As far as I can tell, the largest number R can take has 308 digits > (1+E308). >
This is not a correct statement. The magnitude of the largest 64-bit double precision floating point number in R is approximately 1E308. The internal storage in R (and in most computers today) contains only the first 53 binary digits of the number multiplied by a power of 2. Please see R FAQ 7.31 and the Goldberg article referenced there. The bc results Jim suggested will get you the several hundred digits of the full precision number, but that is not what R sees. The best way to see the exact number internally stored in R is the sprintf %a format sprintf("%+13.13a", x) > sprintf("%+13.13a", .66) [1] "+0x1.51eb851eb851fp-1" > sprintf("%+13.13a", 1-.34) [1] "+0x1.51eb851eb851ep-1" > sprintf("%+13.13a", .66-(1-.34)) [1] "+0x1.0000000000000p-53" > In the .66 display, the repeating hex (51eb8) was rounded, in the 1-.34 display it was chopped. The difference between these two numbers is not 0. Rich [[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.