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From: Ian Kelly <ian.g.kelly@gmail.com>
Date: Wed, 29 May 2013 10:50:47 -0600
Subject: Re: Short-circuit Logic
To: Python <python-list@python.org>
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On Wed, May 29, 2013 at 8:33 AM, rusi <rustompmody@gmail.com> wrote:
> 0.0 == 0.0 implies 5.4 == 5.4
> is not a true statement is what (I think) Steven is saying.
> 0 (or if you prefer 0.0) is special and is treated specially.

It has nothing to do with 0 being special.  A floating point number
will always equal itself (except for nan, which is even more special),
and in particular 5.4 == 5.4.  But if you have two different
calculations that produce 0, or two different calculations that
produce 5.4, you might actually get two different numbers that
approximate 0 or 5.4 thanks to rounding error.  If you then compare
those two ever-so-slightly different numbers, you will find them
unequal.