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Re: cosine/haversine method
From: Chuck Taylor
Date: 2001 Feb 10, 10:48 PM
From: Chuck Taylor
Date: 2001 Feb 10, 10:48 PM
Russell Sher wrote: > > Does anyone have much experience using the cosine/haversine method of sight > reduction? As I understand it, this will calculate Hc, after which the > azimuth has to found using tables or formula. I am interested in finding > some suggestions on what is perhaps the easiest way to find Zn (or Z)... > (ABC tables, formula etc...) Russell, The traditional way, per the 1943 Bowditch, was to use the formula sin Z = sin t * cos d * sec h which was worked out with tables of the logarithms of the various trigonometric functions. With a modern calculator, this would be equivalent to sin Z = (sin t * cos d) / (cos h) Chuck Taylor Everett, WA, USA