Adjective
nonplanar (not comparable)
Not planar.
Additionally, subdividing a graph cannot turn a nonplanar graph into a planar graph: if a subdivision of a graph G has a planar drawing, the paths of the subdivision form curves that may be used to represent the edges of G itself. Source: Internet
"Extended Hückel MO theory" ( EHT ) applies to both sigma and pi electrons, and has its origins in work by William Lipscomb and Roald Hoffmann for nonplanar molecules in 1962. Source: Internet
Kazimierz Kuratowski stated in 1930 that K 3,3 is nonplanar, citation. Source: Internet
The more difficult direction in proving Kuratowski's theorem is to show that, if a graph is nonplanar, it must contain a Kuratowski subgraph. Source: Internet
More generally, the genus of a graph is the minimum genus of a two-dimensional surface into which the graph may be embedded; planar graphs have genus zero and nonplanar toroidal graphs have genus one. Source: Internet
This allows the correctness of a planarity testing algorithm to be verified for nonplanar inputs, as it is straightforward to test whether a given subgraph is or is not a Kuratowski subgraph. citation. Source: Internet