[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

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.

*To*: a.watson@xxxxxxxxxxxxxxxx*Subject*: Re: arithmetic issues*From*: Taylor Campbell <campbell@xxxxxxxxxx>*Date*: Tue, 25 Oct 2005 05:00:10 +0000 (UTC)*Cc*: qrczak@xxxxxxxxxx, srfi-77@xxxxxxxxxxxxxxxxx*Delivered-to*: srfi-77@xxxxxxxxxxxxxxxxx*In-reply-to*: <435C5290.9000306@xxxxxxxxxxxxxxxx> (a.watson@xxxxxxxxxxxxxxxx)*Sender*: Taylor Campbell <campbell@xxxxxxxxxx>*User-agent*: IMAIL/1.21; Edwin/3.116; MIT-Scheme/7.7.90.+

Date: Sun, 23 Oct 2005 22:18:40 -0500 From: Alan Watson <a.watson@xxxxxxxxxxxxxxxx> Taylor Campbell wrote: > 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? The IEEE flonum standard precisely defines the conditions under which NaNs are produced. For example, in conventional arithmetic, zero divided by zero is not defined, but in IEEE flonum arithmetic, zero divided by zero is defined to yield a NaN. It is defined for the sake of computational convenience; what NaN denotes mathematically is the condition of an undefined operation, even if it exists as a value that IEEE flonum operations can produce. There is a distinction between mathematical definedness and IEEE specification for pragmatic reasons.

**Follow-Ups**:**Re: arithmetic issues***From:*Alan Watson

**References**:**Re: arithmetic issues***From:*Alan Watson

- Prev by Date:
**Re: reading NaNs** - Next by Date:
**Re: arithmetic issues** - Previous by thread:
**Re: arithmetic issues** - Next by thread:
**Re: arithmetic issues** - Index(es):