X-Authentication-Warning: delorie.com: mail set sender to geda-user-bounces using -f X-Recipient: geda-user AT delorie DOT com Message-ID: <20150914210429.5063.qmail@stuge.se> Date: Mon, 14 Sep 2015 23:04:29 +0200 From: "Peter Stuge (peter AT stuge DOT se) [via geda-user AT delorie DOT com]" To: geda-user AT delorie DOT com Subject: Re: [geda-user] Apollon Mail-Followup-To: geda-user AT delorie DOT com References: <20150913140631 DOT 1da1b78d AT jive DOT levalinux DOT org> <201509131529 DOT t8DFTUVS022118 AT envy DOT delorie DOT com> <20150914175929 DOT 22829 DOT qmail AT stuge DOT se> <074A28AA-547E-4B71-8D81-30D2CB1B74F3 AT noqsi DOT com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <074A28AA-547E-4B71-8D81-30D2CB1B74F3@noqsi.com> Reply-To: geda-user AT delorie DOT com Errors-To: nobody AT delorie DOT com X-Mailing-List: geda-user AT delorie DOT com X-Unsubscribes-To: listserv AT delorie DOT com Precedence: bulk John Doty wrote: > > I disagree very strongly with floating point, but using a fixed-size > > decimal is an important improvement! > > The trouble is that common computer numerics do not actually obey the > same rules as mathematical numbers. Nod. > Rational numbers fix these problems. .. > For rendering on a grid, use fixed or floating point. The rationals > that fall on your grid are a set of measure zero, anyway. Output (rendering on grid) is one issue, and is easy enough to deal with in isolation. But input (rotate by 60 degrees) is another issue, and less easy to handle, because it's very important for usability that user input->output and vice versa is also closed. Fun! //Peter