Gypaets/polygonAdja​cencyMatrix

Polygon adjacency matrix calculation for triangulations using MATLAB.

% Definition
polygonAdjacencyMatrix calculates the adjacency matrix of the polygons
defined with a triangulation's connectivity list cL. Fast and fully
vectorized approach.
% Usage
Input:
cL: (n x 3) connectivity list of the triangulation.

Output:
pAM: (n x n) polygon adjacency matrix.
% Example
% Create triangulation from 100000 random points
pointsC=rand(100000,2);
X=pointsC(:,1);
Y=pointsC(:,2);
tri=delaunayTriangulation(X,Y);
% Extract connectivity list
cL=tri.ConnectivityList;
% Calculate polygon adjacency matrix
tic
pAM = polygonAdjacencyMatrix(cL);
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