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Re: arithmetic issues

This page is part of the web mail archives of SRFI 77 from before July 7th, 2015. The new archives for SRFI 77 contain all messages, not just those from before July 7th, 2015.

   Date: Sun, 23 Oct 2005 21:12:39 -0500
   From: Alan Watson <a.watson@xxxxxxxxxxxxxxxx>

   Taylor Campbell wrote:
   > NaN is *not* a numeric result; it's not a number!  It represents the
   > condition of a computation whose meaning is undefined; it's not a
   > defined result.

   Your statements about NaNs are correct in the context of mathematical 
   numbers but not in the context of IEEE floating point numbers.

I'm definitely not an expert on IEEE 754, and I'd not trust myself to
argue anything regarding detailed semantics of it, but I think it's
pretty plain & straightforward that what NaN represents is not a
number due to an undefined mathematical operation.  Can you elaborate
on what you meant here?