Roger Hui wrote: > The limit is 5. Roger, you're absolutely correct. This example is one where a 53-bit mantissa gives 100, while a 64-bit mantissa gives 5. It is due to Jean-Michel Muller.
I took the particular formulation from William Kahan's paper (discussion starts at page 14) <http://www.cs.berkeley.edu/~wkahan/Mindless.pdf> Kahan is well worth reading on floating-point issues. His polemical style is either amusing or annoying, depending on your taste. However, he is not a crank: he was the prime architect of the IEEE floating-point standard, and in 1989 received the Turing Award for his work in numerical analysis. Best wishes, John ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
