> In this particular case, it is slightly odd that we can't get an exact > answer for operations that could in principle be carried out using > integer arithmetic, but we're actually calculating log(8)/log(2). > > (Curiously, the same effect is not seen on Linux or Solaris until > > > log2(2^29)-29 > [1] 3.552714e-15 > >
But it's a nice example of the risks of using tests for exact equality (via ==, say)with floating point arithmetic -- even when it **seems** that we have integers. I'll bet a bunch of my code would flop because of this. -- Bert Gunter Genentech Non-Clinical Statistics South San Francisco, CA "The business of the statistician is to catalyze the scientific learning process." - George E. P. Box ______________________________________________ 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
