l]) or it is a Voronoi vertex circumcenter or negative circumcenter) associated with some triangle containing [p.

CIRCUM Subroutine which computes the circumcenter of a spherical triangle defined by user-specified vertices on the unit sphere.

Hence Voronoi edges are portions of perpendicular bisectors of geodesics joining pairs of nodes, and Voronoi vertices are circumcenters or negative circumcenters of triangles with vertices in S.

Thus, given a Delaunay triangulation, the Voronoi region associated with a node is defined by the (cyclically) ordered sequence of circumcenters of the triangles containing the node.

If the nodes are contained in a single hemisphere, however, the set of Voronoi vertices is a superset of the triangulation circumcenters.

In the case of collinear nodes, [MATHEMATICAL EXPRESSION NOT REPRODUCIBLE IN ASCII] will contain null triangles, but B their circumcenters are well defined.

b] [is not equal to] 0, computing the 2N - 4 triangle circumcenters Woronoi vertices) and circumradii, and storing a set of adjacency lists similar to LIST, but containing triangle indexes instead of nodal indexes.

In addition, we've also shown that all orthotetrahedrons (=tetrahedrons with orthocenter) have circumcenter, centroid, and orthocenter to be collinear.

Table 2-1] Other centers of tetrahedron Position in Position in Centers 2D Geometry 3D Geometry Circumcenter A point where three A point where perpendicular bisectors perpendicular bisecting intersect planes intersect Centroid A point where three A point where median medians intersect planes (Planes with a edge and its opposite edge's middle point) intersect Excenter A point where exterior A point where exterior angle bisectors intersect dihedral-bisecting planes intersect Centers Property Circumcenter Becomes the center of the circumcircle and the circumsphere, respectively Centroid Divides the line which connects a point and the opposite planes' centroid as 2:1, 3:1 respectively Excenter Becomes the center of the excircle and the exosphere, respectively