Editing Circle graph (section)

{{Short description|Intersection graph of a chord diagram}}
{{For|the chart|Pie chart}}
{{For|other diagrams|Circle diagram|Smith chart|Nyquist plot}}
[[Image:Circle graph and circle model.svg|thumb|175px|A circle with five chords and the corresponding circle graph.]]
In [[graph theory]], a '''circle graph''' is  the [[intersection graph]] of a [[Chord diagram (mathematics)|chord diagram]]. That is, it is an [[undirected graph]] whose vertices can be associated with a finite system of [[Chord (geometry)|chords]] of a [[circle]] such that two vertices are adjacent if and only if the corresponding chords cross each other.