Open3d European clustering

One 、 brief introduction

Euclidean clustering is a classical clustering method , Its principle and DBSCAN Somewhat similar , It also belongs to a clustering method based on density and distance , The algorithm process is relatively simple , There are mainly the following steps ：
（1） From any point （ Seed point ） set out , Search for adjacent points around it , Then it is considered that these points should belong to the same category , And mark these points by category .
（2） Use adjacent points as new seed points , repeat （1） The process in , Until the adjacent point cannot be searched , Then the points found at this time are considered to be a kind of .
（3） Find the next unmarked point , repeat （1）（2） The process of , Until all points are marked by the search , Then the algorithm ends .

because Open3D European clustering not found in "_", Therefore, it is specially implemented here for subsequent use .

Two 、 Implementation code

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