# Incremental hierarchical clustering

I have an online k-means algorithm following this scheme:

Let x a new data-point, and c the nearest cluster center
if( distance(x, c) > threshold )
x becomes a new cluster center
else assign x to c


In order to speed up the search for nearest center, is it possible to have a hierarchical structuring of centers, that we can incrementally update each time a new data-point is considered (i.e. without recomputing the whole hierarchy) ?

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