Topological Sweep in Degenerate Cases

  • Eynat Rafalin
  • Diane Souvaine
  • Ileana Streinu
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 2409)


Topological sweep can contribute to efficient implementations of various algorithms for data analysis. Real data, however, has degeneracies. The modification of the topological sweep algorithm presented here handles degenerate cases such as parallel or multiply concurrent lines without requiring numerical perturbations to achieve general position. Our method maintains the O(n 2) and O(n) time and space complexities of the original algorithm, and is robust and easy to implement. We present experimental results.


Intersection Point Computational Geometry Degenerate Case Matching Sequence Elementary Step 
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Copyright information

© Springer-Verlag Berlin Heidelberg 2002

Authors and Affiliations

  • Eynat Rafalin
    • 1
  • Diane Souvaine
    • 1
  • Ileana Streinu
    • 2
  1. 1.Department of Electrical Engineering and Computer ScienceTufts UniversityMedford
  2. 2.Department of Computer ScienceSmith CollegeNorthampton

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