Re: Round-off error?
- To: mathgroup at smc.vnet.net
- Subject: [mg131942] Re: Round-off error?
- From: Richard Fateman <fateman at cs.berkeley.edu>
- Date: Mon, 4 Nov 2013 23:17:19 -0500 (EST)
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On 11/1/2013 11:21 PM, Bill Rowe wrote: > > shows the two machine precision numbers differ by 1 bit and > consequently are considered equal by Equal as documented. > > This type of issue is inherent in floating point arithmetic done > on any modern computer. > This is not at all true. Mathematica chooses to implement a fuzzy version of equality that does not correspond to any hardware floating-point operation on any modern computer that I am aware of. Mathematica's definition of Equal is a misfeature that leads to many contradictions to ordinary arithmetic results. This has been pointed out numerous times and presumably will continue to provoke questions indefinitely. RJF >