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[Marc Mörig <>]

Dear CGAL maintainers,

in CORE_Expr.h there is twice the call

x.approx(53,1024);

meant to improve the internal approximation in x to double quality.
After a call x.approx(r,a) the internal approximation z is such that

|x - z| <= max{ |x|2^{-r}, 2^{-a}  }

So that call wastes precision if x is in the underflow range. It should be

x.approx(53,1075);

since the smallest (positive nonzero) double is 2^{-1074}.

Regards,
Marc Mörig

--
Marc Mörig                                 Email:  

Institut für Simulation und Graphik        Phone: +49 391 67-52858
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