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From: John Maddock (john_at_[hidden])
Date: 2005-12-03 14:09:29

> ld = hi + low as above is not among the bit patterns he lists as
> valid. If you apply the definition of epsilon to the "normal" long
> doubles only, then you get a value like the one Paul Bristow computed
> for NTL's quad_float.

I agree: that explanation is quite explicit when it says it follows Kahan's
"double double" and the IEEE spec. So the low part must be normalised so
that it's bit's "follow on" from those in the high part. As it stands,
1+numeric_limits<>::epsilon() should evaluate to 1, but we really need to
check this out. Does anyone of a numerical inclination, want to run some
tests on Darwin?


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