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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>
To:	geda-user AT delorie DOT com
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
References:	<20150913140631 DOT 1da1b78d AT jive DOT levalinux DOT org> <201509131529 DOT t8DFTUVS022118 AT envy DOT delorie DOT com> <B0EDB76E-F0DE-4A05-97FC-A405489ACA5A AT noqsi DOT com> <201509131824 DOT t8DIOCBc028428 AT envy DOT delorie DOT com> <B03281A2-123E-4F54-B3AA-CB8CCB09F1B1 AT noqsi DOT com> <201509132031 DOT t8DKVH0P000824 AT envy DOT delorie DOT com> <AB671235-711B-4ECD-9015-515A5BFC6955 AT noqsi DOT com> <201509132148 DOT t8DLmxI6003481 AT envy DOT delorie DOT com> <D8151856-4B93-4826-A80F-E00578A2E93C AT noqsi DOT com>
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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.

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