accumulation point

英語（米国） (en-US) 英語（イギリス） (en-GB)

名詞

(topology, "of" a subset of a topological space) Given a subset S of a topological space X, a point x whose every neighborhood contains at least one point distinct from x that belongs to S.

日本語の意味

位相空間内の部分集合において、その全ての近傍内に、自己とは異なる集合の点が存在する点。 / 集合の任意の近傍が、その集合内の他の点を必ず含む点。

英語の意味

(topology, "of" a subset of a topological space) Given a subset S of a topological space X, a point x whose every neighborhood contains at least one point distinct from x that belongs to S.

このボタンはなに？

A point x is an accumulation point of S if every neighborhood of x contains a point of S different from x.

点xは、xの任意の近傍がxとは異なるSの点を含むとき、Sの集積点である。

詳細

意味（1）

(topology, "of" a subset of a topological space) Given a subset S of a topological space X, a point x whose every neighborhood contains at least one point distinct from x that belongs to S.

LEMMA 5.2 Let X be a Hausdorff space and A a subset of X. A point a∈X is an accumulation point of A if and only if a is a limit point of A.

詳細

意味（2）

(mathematical analysis, "of" a sequence) Given a sequence sᵢ, a point x whose every neighborhood contains at least one element of the sequence distinct from x.

意味（3）

(systems theory, dynamical systems, chaos theory) For certain maps, a point beyond which periodic orbits give way to chaotic ones.

The chaotic set (not necessarily attracting) is formed after the first accumulation point (a_∞≈3.570 for the logistic mapping) is reached. In the chaotic region of the logistic map the periodicity re-emerges in periodic windows which are bounded by the accumulation point from the right and by the saddle-node bifurcation from the left. A reverse bifurcation sequence occurs above the accumulation point.

詳細

accumulation points （ plural ）