Extract a list of triangles from a triangulation object
This function extracts a list of triangles
from an triangulation object created by tri.mesh.
triangles(tri.obj)
tri.obj |
object of class |
The vertices in the returned matrix (let's denote it with
retval) are ordered counterclockwise. The columns trx
and arcx, x=1,2,3 index the triangle and arc, respectively,
which are opposite (not shared by) node nodex, with
trix=0 if arcx indexes a boundary arc. Vertex indexes
range from 1 to n, the number of nodes, triangle indexes from 0
to nt, and arc indexes from 1 to na = nt+n-1.
A matrix with columns node1, node2, node3,
representing the vertex nodal indexes,
tr1, tr2, tr3, representing neighboring triangle
indexes and arc1, arc2, arc3 reresenting arc
indexes.
Each row represents one triangle.
Albrecht Gebhardt <albrecht.gebhardt@aau.at>, Roger Bivand <roger.bivand@nhh.no>
# use the smallest Franke data set data(franke) fr3.tr<-tri.mesh(franke$ds3$x, franke$ds3$y) triangles(fr3.tr)
Please choose more modern alternatives, such as Google Chrome or Mozilla Firefox.