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Re: Motion 6

Vincent Lefevre wrote:

On 2009-09-16 18:35:54 -0700, Dan Zuras Intervals wrote:

	In particular, the semi infinite sets have no representation
	in midrad.  An important subset in need of representation.


That's not a problem. If you have a semi-infinite set, this means
that the error bound is infinite. So, this isn't much different
from the whole set R of the real numbers.


The little difference may be decisive, though, for example when
checking algebraic numbers for their sign, using multiprecision
arithmetic. x in 1e-10000 + [0,Inf] encodes sign information,
which is lost when going to midrad.


Arnold Neumaier