NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Azimuth and Declination formulae
From: Herbert Prinz
Date: 2005 Jul 20, 12:56 -0400
From: Herbert Prinz
Date: 2005 Jul 20, 12:56 -0400
Lu Abel wrote: > The whole reason for versines and haversines was to allow sight > reductions to be done using logarithms (and therefore the requisite > multiplications become additions); but logs are not defined for negative > numbers, hence the need to shift everything to have a positive value. The fact that the trigonometric functions are much older than negative numbers and basically all spherical trig problems could be solved before the introduction of negative numbers shows that something is not right with this historical theory. > Therefore all > GPS's actually use the haversine formula for calculating the distance > between two points. Since all GPS receivers currently on the market display distance along the geodesic, I would be surprised if _any_ of them used the haversine formula. But how would you know? Did you look inside? Herbert Prinz
