Geometry-aware Hashing of GeoJSON objects
Just a quick little feature I implemented over the weekend. TODO: Assure that polygons can be palindromic as well
Geometry-aware Hashing of GeoJSON objects launched on May 26, 2024 with 7 votes, #1,618 of 4,539 launches that month and more than 75% of that year's launches. The site was still online in September 2026, 2 years on.
What it does
Whenever you want to compare two (or more) huge lists with each other, you quickly end up using hashes. You can associate your objects to an hash, put them in a hash map, and lookup values (in this case, duplicates) in O(1) time, resulting in far less computationally expensive operations. In GeoJSON each FeatureCollection (you see this a map, with added Points, Lines, and Areas) contains Features , which contain Geometry , which in the case of LineString and Polygon are a set of coordinates. Hashing produces a (expected) unique value for one object. But the underlying information that a Geometry encodes is not a fixed-set of coordinates, but rather an area ( Polygon ) or a line ( Line…from altayakkus.dev
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