Problem 45230. Remove duplicated triangles

Created by Mathworlds

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Input T is a triangulation (triplet list of indices -positive integers-, each index refering to a vertex number in a corresponding vertices list).It sometimes happens a triangle may be duplicated several times. The goal of this problem is to remove all the duplicated triangles of T, and to keep only one.For instance if :<pre class="language-matlab">T_in = [1 2 3;...
 4 5 6;...
 1 2 3;...
 7 8 9;...
 6 4 5;...
 10 11 12;...
 2 1 3;...
 8 7 9;...
 10 11 12]
</pre>then the output must be :<pre class="language-matlab">T_out = [1 2 3;...
 4 5 6;...
 7 8 9;...
 10 11 12]
</pre>since rows [1 2 3], [6 4 5], [2 1 3], [8 7 9], and [10 11 12] are just duplicata. Indeed triangle [i2 i1 i3] is the same as triangle [i1 i2 i3] for example.Hypothesis :<ul><li>T is always a N x 3 integer matrix with N &gt; 0 (non empty matrix)</li><li>Each row / triangle of T always contains three distinct integers</li></ul>Good work Matlab bro ! :)

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Last Solution submitted on Dec 30, 2020

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3d duplicat edge find geometry index indices mathematics mesh mesh processing surface triangle triangulation trimesh triplet vertex vertices

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Problem 45230. Remove duplicated triangles

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