Problem 45256. Query a vertex neighbors

Created by Nicolas Douillet

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First input T is a triangulation connectivity indices list (triplet list of indices -positive integers-, each index refering to a vertex number in a corresponding vertices list).Second input i is a vertex index (positive integer).The purpose of this function is to query the list L of all i neighbor indices.For instance if<pre class="language-matlab">T = [1 2 4;...
 2 3 4;...
 5 6 8;...
 6 7 8;...
 1 2 5;...
 2 5 6;...
 2 3 6;...
 3 6 7;...
 3 4 7;...
 4 7 8;...
 4 1 8;...
 1 8 5]
</pre>and i = 3, then the function should return<pre class="language-matlab">L = [2, 4, 6, 7]
</pre>since 2, 4, 6, and 7 are all part of triangles / rows in which 3 is also a vertex member.Hypothesis :- Output L doesn't need to be ordered, but must not contain duplicated index.- Output L is a row vector , and if the vertex index is not in the list , the function must of course return the empty set, [].

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Last Solution submitted on Oct 14, 2020

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3d edge face facet find geometry index indices mathematics mesh mesh processing neighbor surface triangle triangulation trimesh vertex vertices

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Problem 45256. Query a vertex neighbors

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Problem 45256. Query a vertex neighbors

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