From owner-qed Thu Oct 27 10:26:49 1994 Received: from localhost (listserv@localhost) by antares.mcs.anl.gov (8.6.4/8.6.4) id KAA25208 for qed-out; Thu, 27 Oct 1994 10:26:21 -0500 Received: from catseye.idbsu.edu (catseye.idbsu.edu [132.178.200.125]) by antares.mcs.anl.gov (8.6.4/8.6.4) with SMTP id KAA25202 for ; Thu, 27 Oct 1994 10:26:14 -0500 Message-Id: <199410271526.KAA25202@antares.mcs.anl.gov> Received: by catseye.idbsu.edu (1.38.193.4/16.2) id AA08684; Thu, 27 Oct 1994 09:26:58 -0600 Date: Thu, 27 Oct 1994 09:26:58 -0600 From: Randall Holmes To: qed@mcs.anl.gov Subject: Floating-point Sender: owner-qed@mcs.anl.gov Precedence: bulk I agree absolutely that floating point numbers, whatever they are, are not representations of reals :-) A genuine ADT for real numbers would be an interesting (feasible but hard) project. --Randall Holmes P.S. This becomes a serious problem when one attempts, as our department is attempting with me and my students, among others, as guinea pigs, to teach elementary calculus using Maple or other symbolic calculation software. Both bugs in the software and effects of round-off error can produce phenomena which are very confusing to students, and have done so in practice, and the students have no background which would help them to figure out why they are getting into trouble. I can see how sound and debugged symbolic computation software targetted at college students could be very valuable in teaching, but Maple (like any other package I am aware of) has none of these properties. Keep it away from the QED database :-)