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arXiv · 1912.09585

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

Martin Chalela·Emanuel Sillero·Luis Pereyra·Mario Alejandro García·Juan B. Cabral·Marcelo Lares·Manuel Merchán
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Abstract

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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Martin Chalela, Emanuel Sillero, Luis Pereyra, Mario Alejandro García, Juan B. Cabral, Marcelo Lares, Manuel Merchán. 2019-12-19. GriSPy: A Python package for Fixed-Radius Nearest Neighbors Search. https://arxiv.org/abs/1912.09585

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