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GriSPy: A Python package for Fixed-Radius Nearest Neighbors Search

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 نشر من قبل Martin Chalela Mr.
 تاريخ النشر 2019
  مجال البحث فيزياء
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We present a new regular grid search algorithm for quick fixed-radius nearest-neighbor lookup developed in Python. This module indexes a set of k-dimensional points in a regular grid, with optional periodic conditions, providing a fast approach for nearest neighbors queries. In this first installment we provide three types of queries: $bubble$, $shell$ and the $nth-nearest$; as well as three different metrics of interest in astronomy: the $euclidean$ and two distance functions in spherical coordinates of varying precision, $haversine$ and $Vincenty$; and the possibility of providing a custom distance function. This package results particularly useful for large datasets where a brute-force search turns impractical.



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