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Re: inconsistency with Inequality testing and Floor

  • To: mathgroup at smc.vnet.net
  • Subject: [mg60037] Re: inconsistency with Inequality testing and Floor
  • From: "Brett Patterson" <muckle.moose at gmail.com>
  • Date: Tue, 30 Aug 2005 04:42:57 -0400 (EDT)
  • References: <dek8a1$aao$1@smc.vnet.net><dep7p6$f1a$1@smc.vnet.net>
  • Sender: owner-wri-mathgroup at wolfram.com

Hi Jean-Marc,

Thanks for your response...but I don't really understand it!

My problem is that the logical test (<) and the numerical operation
Floor seem to give different and inconsistent results on the same
input. Regardless of the reasons for that, due to machine
representations, etc, I feel that these operations should be designed
to be consistent. My input is the value of a variable x. The logical
test tells me that x >= 1, but the result of Floor[x] is 0. This is
surely unintuitive and inconsistent.

In your example, setting $MaxExtraPrecision to a larger number did not
change the value or Floor[x], and it does not change the result of x
>=1. So I don't understand what you were trying to demonstrate by setting $MaxExtraPrecision to 1000.

Cheers,
Brett


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