Complexes 6 Simplicial complex

نویسنده

  • Tamal K. Dey
چکیده

Definition 20 (simplex). A k-simplex σ is the convex hull of a set P of k + 1 affinely independent points. In particular, a 0-simplex is a vertex, a 1-simplex is an edge, a 2-simplex is a triangle, and a 3-simplex is a tetrahedron. A k-simplex is said to have dimension k. A face of σ is a simplex that is the convex hull of a nonempty subset of P. Faces of σ come in all dimensions from zero (σ’s vertices) to k; σ is a face of σ. A proper face of σ is a simplex that is the convex hull of a proper subset of P; i.e. any face except σ. In particular, the (k − 1)-faces of σ are called facets of σ; σ has k + 1 facets. For instance, the facets of a tetrahedron are its four triangular faces.

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تاریخ انتشار 2017