Subject: Re: double line bug & nautical miles<br/>
Date: Nov 25, 2001 @ 03:27<br/>
Author: orc@orcoast.com (orc@...)<br/>
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<div id="ygrps-yiv-610052104">grant<br/>
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<blockquote><span title="ireply"> &gt; Michael:<br/>
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&gt; &gt; it is n46d15m precisely to as many digits of zero as you like<br/>
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&gt; <br/>
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&gt; Working to the nearest metre (the US nautical league comes out at a<br/>
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&gt; pleasing 5555m), <br/>
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<br/>
<br/>
 </span></blockquote>such fortunate coincidence only enhances your already sensible choice of the integral meter for the first try<br/>
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still pertinent for a followup try or tries are the actual next 5 digits of the metric united states nautical league <br/>
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since i believe at least 4 of them would be legally & scientifically significant<br/>
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but i am admittedly ahead of myself because a full meter is the window of choice & opportunity here<br/>
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while my curiosity embraces not only the tripoint in the abstract but also its threshold of authenticity <br/>
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or window of reality <br/>
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or what might be called the range or even yikes the area of the point<br/>
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<blockquote><span title="ireply"> &gt; I make 3nm US to be .0720365 degrees of longitude<br/>
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&gt; measured along the N46d15m parallel, which puts your tripoint at:<br/>
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&gt; <br/>
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&gt;       N46d15m00.00s W124d09m19.33s<br/>
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<br/>
<br/>
 </span></blockquote>excellent<br/>
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that appears to get it down to about the square foot<br/>
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even if it pretends a little to improve on your basic meter<br/>
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in any case we have credibly plotted the first of the 20 united states federal maritime tripoints well beyond most gps range<br/>
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& that accomplishment alone substantially advances a 2year quest<br/>
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<blockquote><span title="ireply"> &gt; A bit of faffing around with spherical trig comes up with a<br/>
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&gt; reassuringly close value measured along the west-looking great circle:<br/>
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&gt; <br/>
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&gt;       N46d14m59.92s W124d09m19.33s<br/>
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&gt; <br/>
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&gt; That 0.08s difference to the south means that the westward line of<br/>
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&gt; sight comes out 2.5m farther to the south at 3nm than the westward<br/>
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&gt; parallel of latitude. (The tripoint necessarily also shifts<br/>
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&gt; submillimetrically eastwards, but not something that can be worried<br/>
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&gt; about with a boat and a GPS.)<br/>
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 </span></blockquote>yes all this is reassuring<br/>
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& do you agree i can run the computation out to the 5th decimal place without any loss of authenticity by simply using the full 5 decimal places of the submillimetric nautical mile standard<br/>
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it seems so to me <br/>
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& i think i can just continue to solve it from here as a ratio problem since you have given me 3 of the 4 terms <br/>
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but i might also be over my head mathematically<br/>
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heck i just confused a loxodrome for a great bagel route<br/>
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m</div>