[R] one is not one

Philipp Pagel philipp.pagel.lists at t-online.de
Sat Oct 21 12:53:16 CEST 2006

On Sat, Oct 21, 2006 at 11:04:13AM +0200, Patrick Giraudoux wrote:
> Which means that actually sum(x) is NOT considered equal to 1...
> Any idea about what is going wrong?

Others have already pointed out the problem and I would like to add a
reference to a classical paper on this topic:

David Goldberg
What Every Computer Scientist Should Know About Floating-Point Arithmetic
Computing Surveys, 1991

Reprints can be found in many places online - e.g. here:



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