Abstract
A triangulation of a planar point set S is a maximal plane straight-line graph with vertex set S. In the minimum-weight triangulation (MWT) problem, we are looking for a triangulation of a given point set that minimizes the sum of the edge lengths. We prove that the decision version of this problem is NP-hard, using a reduction from PLANAR 1-IN-3-SAT. The correct working of the gadgets is established with computer assistance, using dynamic programming on polygonal faces, as well as the β-skeleton heuristic to certify that certain edges belong to the minimum-weight triangulation.
Supplemental Material
Available for Download
Precise description of the point sets that were used for the gadgets described in the article (unrefereed material)
Extended version of the article with a technical appendix that includes the data for all gadgets and documents the computer program; also available under http://arxiv.org/abs/cs/0601002 (unrefereed material)
Source code for a Python program that verifies that the gadgets fulfill the desired properties (unrefereed material)
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Index Terms
- Minimum-weight triangulation is NP-hard
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