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A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Dozier Formula
From: Aubrey O´Callaghan
Date: 2001 Nov 20, 6:01 AM
From: Aubrey O´Callaghan
Date: 2001 Nov 20, 6:01 AM
Dan, The reason for going rectangular to polar is so that the solution comes out in the correct quadrant. You can appreciate that arctan (A/B) = arctan(-A/-B). One solution is in the NE quadrant the other in the SW quadrant. Some programming languages have a function atan2 which takes 2 arguments and ensures that the computed angle is correct. (m.soft excel has this). The R->P is a workaround for calculators. Aubrey. At 14:36 19/11/01, you wrote: >Rewritten as because of the result coming out 180 degrees off and of using >the Polar-to-rectangular function: > tan(Zn - 180) = sin LHA / cos LHA * sin L - cos L * tan d > >Then *using invented notation* rewritten again as: > Zn = 180 + R->P (sin LHA * cos d, cos LHA * cos d * sin L - cos L > * tan d > >Now can someone explain what the COMMA after the first cos d stands for? > > >Dan Hogan WA6PBY >C27 "Gacha" >dhhogan@verimail.com >Nav-L Page: http://www.wa6pby.com
