[R] one is not one

[Philipp Pagel]

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:

http://www.physics.ohio-state.edu/~dws/grouplinks/floating_point_math.pdf

cu
	Philipp

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