Can you describe a concrete lookup for finding nearby drivers?
Hash the rider's coordinates to their H3 cell at precision 9 (roughly 174 meters). Extract the level-8 parent cell to identify the region. Query a hash table for the six level-8 neighbor cells. Drivers indexed by cell ID are found in microseconds—no distance math, no sorting, just table probes.
Answered in
Why Uber Tiles the Planet in HexagonsHexagons with equidistant neighbors replace lat/long trigonometry with O(1) table lookups for finding nearby drivers and calculating surge pricing.
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