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A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
From: Frank Reed
Date: 2019 Aug 22, 04:51 -0700
Tony, you wrote:
"I wonder how could formulas look like to calculate, say, a distance between two points given in such a way?"
It's not a new coordinate system. It's just a lookup table, a code that "decodes" to a latitude and longitude, and then the calculation proceeds as normal. For a simpler code, just use a letter lookup: A=0, B=1, etc. (and maybe Z for a negative lat/lon, Y for pos lon). In that code, 41N, 72W would be "EBZHC" and 41.1S,72.2E would be "ZEBBYHCC". This is an inefficient system, but it works. Google has a similar coding system that is available on any device: https://plus.codes/, and it's displayed prominently in Google Maps. Just like what3words, it's a code that "decodes" to lat/lon, but it's designed to look more like a traditional postal code. Of course there are many apps and tools that allow location-sharing, so creating these codes (of any type) has marginal benefit.
Frank Reed