The thing that annoys me as a software engineer with background in mathematics is that it's hard to find pure transformation formulae between these geodesic coo

The thing that annoys me as a software engineer with background in mathematics is that it's hard to find pure transformation formulae between these geodesic coordinate systems, or at least was 5+ years ago when I last played with it. I get all the gotchas, but formula is much easier for me to get my head around rather than these articles which are centered around me having to learn a lot of terminology just to be able to do a transformation between coordinate systems. Even if that formula was accompanied with a correction table for particular use cases.