How could I utilize algorithms for nearest neighbor search to do fixed radius search? -


there lots of works nearest neighbor search problem, wonder if want fixed radius range search, utilize algorithms nearest neighbor search?

perhaps kth-nearest-neighbor search on , on again until find point beyond radius range, suppose might cause lot of waste.

not "there lots of works nearest neighbor search problem," there many questions asked problem. important number of dimensions.

make sure check answer if not sure why dimension important.

high dimensional space

assuming points lie in high dimensional space, should go locality-sensitive hashing (lsh) . nice implementation of algorithm e²lsh. provide slides, if want implement or better understanding of happens. note e²lsh solves randomized version of r-near neighbor problem, call (r, 1 − δ)-near neighbor problem, δ has approximation, mention in manual.

you can check answer regarding lsh here. have used in c++ , recommend fixed radius search want perform!

low dimensional space

use cgal's spatial searching. have used many times case in c++. again, if want implement yourselves, can find plenty information @ nice documentation have , relative google queries.

nice answer way, got +1. :)


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