J4 ›› 2011, Vol. 49 ›› Issue (03): 465-470.

• 数学 • 上一篇    下一篇

有限点集共超球的充分必要条件

 杨定华   

  1. 四川师范大学 数学与软件科学学院, 成都 610066
  • 收稿日期:2010-02-02 出版日期:2011-05-26 发布日期:2011-06-15
  • 通讯作者: 杨定华 E-mail:yangdinghua@msn.com

A Necessary and Sufficient Condition fora Finite Set of Points on a HyperSphere

YANG Dinghua   

  1. College of Mathematics and Software Sciences, Sichuan Normal University, Chengdu 610066, China
  • Received:2010-02-02 Online:2011-05-26 Published:2011-06-15
  • Contact: YANG Dinghua E-mail:yangdinghua@msn.com

摘要:

运用距离几何的理论与方法, 证明n维欧氏空间En中的n维有限点集Σ(A,N+1)={A0,A1,…,AN}在同一个n-1维超球面上的充要条件是: Σ(A,N+1)的距离平方矩阵M(Σ(A,N+1))=(a2kl)(k,l=0,1,…,N)的秩等于n+1. 并给出了三维空间中5点共球的充分必要条件.

关键词: n维欧氏空间, n-1维超球面, 距离平方矩阵,

Abstract:

Using the theory and method of distance geometry, we proved that a necessary and sufficient condition for Σ(A,N+1) being on an (n-1)dimensional hypersphere is that the matrix M(Σ(A,N+1))=(a2kl)(k,l=0,1,…,N) has rank n+1, where M(Σ(A,N+1)) is the distance square matrix of Σ(A,N+1), Σ(A,N+1)={A0,A1,…,AN} is an ndimensional finite set of points in ndimensional Euclidean space. A necessary and sufficient condition for 5 points on a 2dimensional hypersphere was given.

Key words: ndimensional Euclidean space, (n-1)dimensional , hypersphere, distance square matrix, rank

中图分类号: 

  • O184