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Re: inconsistency with Inequality testing and Floor

• To: mathgroup at smc.vnet.net
• Subject: [mg60079] Re: inconsistency with Inequality testing and Floor
• From: "Richard J. Fateman" <fateman at eecs.berkeley.edu>
• Date: Thu, 1 Sep 2005 02:13:13 -0400 (EDT)
• Organization: UC Berkeley
• References: <200508251034.GAA10208@smc.vnet.net> <demmfd$rf1$1@smc.vnet.net>
• Sender: owner-wri-mathgroup at wolfram.com

Andrzej Kozlowski wrote:


> 
> You cannot expect inexact numbers, particularly "borderline cases" as  
> in this example, to obey the usual laws of arithmetic.
> 

These inconsistencies are not inherent in computer arithmetic,
even floating-point arithmetic. They represent choices made by the
designers of Mathematica.  In particular, choosing to allow two
distinct numbers to be numerically equal leads to problems. I
wonder if there is some compensating good reason for this choice
in Mathematica. I am not aware of any reason good enough to
justify this.

Calling a bug a feature does not fix it.

RJF

• Follow-Ups:
  • Re: Re: inconsistency with Inequality testing and Floor
    • From: Andrzej Kozlowski <andrzej@akikoz.net>