"AJP" wrote in message <email@example.com>...
> After triangulating my points (x,y) using delaunay(x,y) I have many undesirable long edges around the outer perimeter of the triangulation.
> Is there any way to prevent these from appearing or modifying them so that edges are computed to more nearby points?
> I am aware that this problem is inherent to the Delaunay Triangulation and has something to do with encroaching on the convex hull of the data, but beyond that I'm lost.
> I have looked at doing a constrained triangulation, but since I have no knowledge of the points or triangulation in advance, I don't know how to specify the constraint matrix.
> Any ideas would be great. Thanks to all for contributions.
I dont know about computing edges to closer points, but you might be able to remove the long edges completely by calculating the alpha shape of your points (search the file exchange for this) for an appropriate value of alpha, then remove any triangles whose centroid falls outside of the alpha shape (tested using inpolygon). You might still need some prior knowledge of the points to choose a value for alpha, which basically defines what you consider to be too long of an edge.
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