Department of Computer Science | Institute of Theoretical Computer Science | CADMO

Theory of Combinatorial Algorithms

Prof. Emo Welzl and Prof. Bernd Gärtner

Mittagsseminar (in cooperation with A. Steger, D. Steurer and B. Sudakov)

Mittagsseminar Talk Information

Date and Time: Tuesday, April 25, 2017, 12:15 pm

Duration: 30 minutes

Location: OAT S15/S16/S17

Speaker: Manuel Wettstein

An Optimal Algorithm for Reconstructing Point Set Order Types from Radial Orderings

Let P be a set of n points in the plane. The order type \chi of P is a function which assigns an orientation (clockwise or counterclockwise) to every ordered triple in P. The radial system R of P describes the (counterclockwise) radial order in which all other points are encountered around each point in P. While given \chi it is easy to construct the corresponding R, the converse is not true and there might be more than one solution. We give an algorithm that takes R as input and, after O(n) time of preprocessing, allows constant-time queries to all order types that are consistent with R.
Joint work with Oswin Aichholzer, Vincent Kusters, Wolfgang Mulzer, and Alexander Pilz.

Upcoming talks     |     All previous talks     |     Talks by speaker     |     Upcoming talks in iCal format (beta version!)

Previous talks by year:   2024  2023  2022  2021  2020  2019  2018  2017  2016  2015  2014  2013  2012  2011  2010  2009  2008  2007  2006  2005  2004  2003  2002  2001  2000  1999  1998  1997  1996  

Information for students and suggested topics for student talks

Automatic MiSe System Software Version 1.4803M   |   admin login