On the Shape of incidence matrix H

[meiyouzidexigua]

Why the shape of established incidence matrix H is n * n?

[Bennie61]

Because the hypergraph is built using a distance-based approach. Specifically, the K-nearest neighbor method is used: each vertex is taken as the center of mass, and each hyperedge is connected to its K-1 nearest neighbor node. If you have n nodes, you have n hyperedges, one for each node.