Homology and Homological Algebra,
نویسنده
چکیده
= convex hull of {a0, . . . , an}. The points a0, . . . , an are geometrically independent if a1 − a0, . . . , an − a0 is a linearly independent set over R. Note that this is independent of the order of a0, . . . , an. In this case, we say that the simplex a0 . . . an is n -dimensional, or an n -simplex. Given a point Pn i=1 λiai belonging to an n-simplex, we say it has barycentric coordinates (λ0, . . . , λn). One can use geometric independence to show that this is well defined. A (proper) face of a simplex σ = a0 . . . an is a simplex spanned by a (proper) subset of {a0, . . . , an}.
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