Coordinate Assignment for Cyclic Level Graphs

Abstract. The Sugiyama framework is the most commonly used concept for visualizing directed graphs. It draws them in a hierarchical way and operates in four phases: cycle removal, leveling, crossing reduction, and coordinate assignment. However, there are situations where cycles must be displayed as such, e. g., distinguished cycles in the biosciences and scheduling processes which repeat in a daily or weekly turn. This excludes the removal of cycles. In their seminal paper Sugiyama et al. introduced recurrent hierarchies as a concept to draw graphs with cycles. However, this concept has not received much attention in the following years. In this paper we supplement our cyclic Sugiyama framework and investigate the coordinate assignment phase. We provide an algorithm which runs in linear time and constructs drawings which have at most two bends per edge and use quadratic area.

• Type: Conference
• Year: 2009
• Where: COCOON
• Authors: Christian Bachmaier, Franz-Josef Brandenburg, Wolfgang Brunner, Raymund Fülöp
• Keywords: COCOON 2009, Combinatorics, Coordinate Assignment, Seminal Paper Sugiyama, Sugiyama Framework