This is an extremely-fast and easy to use KDTree written entirely in modern C#. This is the fastest and simplest to use KDTree that I have been able to find for .NET. The project has thorough documentation and is open-source. This module is a part of the larger Supercluster project.
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A collection of mathematical function and data structures written in C#.
Numerical comparison, vector geometry, polynomial, root solver, statistics, GPS and clustering, and abstract bitmap and draw functions.