Triangulate a planar straight line graph using the Triangle library (http://www.cs.cmu.edu/~quake/triangle.html). The triangulation is a constrained conforming Delaunay triangulation in which additional vertices, called Steiner points, can be inserted into segments to improved the quality of the triangulation. To prevent the insertion of Steiner points on boundary segments, specify Y=1. If the maximum triangle area a is specified, the area of each triangle is not allowed to exceed this value. If the the minimum angle q is specified, no triangle angle is allowed to be below this value.
pslg
(Package: RTriangle) :
Create a Planar Straight Line Graph object
A Planar Straight Line Graph (PSLG) is a collection of vertices and segments. Segments are edges whose endpoints are vertices in the PSLG, and whose presence in any mesh generated from the PSLG is enforced.
providing 
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