Flips in combinatorial pointed pseudo - triangulations with face degree at most four ( extended abstract )
نویسندگان
چکیده
In this paper we consider the ip operation for combinatorial pointed pseudo-triangulations where faces have size 3 or 4, so-called combinatorial 4-PPTs. We show that every combinatorial 4-PPT is stretchable to a geometric pseudo-triangulation, which in general is not the case if faces may have size larger than 4. Moreover, we prove that the ip graph of combinatorial 4-PPTs with triangular outer face is connected and has diameter O(n).
منابع مشابه
Flips in combinatorial pointed pseudo-triangulations with face degree at most four
In this paper we consider the flip operation for combinatorial pointed pseudo-triangulations where faces have size 3 or 4, so-called combinatorial 4-PPTs. We show that every combinatorial 4-PPT is stretchable to a geometric pseudo-triangulation, which in general is not the case if faces may have size larger than 4. Moreover, we prove that the flip graph of combinatorial 4-PPTs is connected and ...
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