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Date: Sun, 13 Sep 2015 19:00:54 -0400
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From: DJ Delorie <dj AT delorie DOT com>
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In-reply-to: <D8151856-4B93-4826-A80F-E00578A2E93C@noqsi.com> (message from
	John Doty on Sun, 13 Sep 2015 16:47:03 -0600)
Subject: Re: [geda-user] Apollon
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> > Also, most rational vectors do not have a rational magnitude.
> 
> If you have a Pythagorean triple (x, y, h), x^2+y^2==h^2, it
> represents an angle arctan(y/x).

Except that h is typically *not* an integer.  Once you go off-integer,
you hit the FPU precision problem, because in the FPU all numbers are
on a "grid".

The only way to avoid the FPU precision problem is to avoid *all*
floating point numbers, rational or otherwise, and stick with
integers.