NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Haversine- how to derive it?
From: Christophe C.
Date: 2015 May 18, 00:28 -0700
From: Christophe C.
Date: 2015 May 18, 00:28 -0700
Hi John,
The versine is bounded by [0, 2] therefore its log values can be both positive and negative - which can lead to errors when reading the log versine value in a table and then when working with that value.
The haversine, being bounded by [0, 1], only has negative log values - *that* is the additional virtue of the haversine.
But personally I prefer to look at the ZD formula as being expressed in terms of versines - it is much easier to remember since the parts of the formula represent real (projected) distances! (see attached drawing)
I hope this helps,
Christophe
File:
