Algorithms for determining the geometrical congruity in two and three dimensions

  • Tatsuya Akutsu
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 650)


This paper discusses the problem of determining the geometrical congruity. O(n log n) time algorithms for point sets in three dimensions and for graphs whose vertices are points in three dimensions are presented, respectively. They are based on Sugihara's algorithm for determining the congruity of polyhedra. Moreover, an O(log n) time O(n) processors parallel algorithm for graphs in two dimensions which works on a CRCW PRAM is presented. In this algorithm, the original problem is transformed into the string matching problem. All the algorithms are optimal and can be modified for computing the canonical forms.


Convex Hull Canonical Form Time Algorithm Random Access Machine String Match Algorithm 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer-Verlag Berlin Heidelberg 1992

Authors and Affiliations

  • Tatsuya Akutsu
    • 1
  1. 1.Mechanical Engineering LaboratoryIbarakiJapan

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