floor plan vs undirected graph

floor plan

noun
  • A layout representation of where the major functional blocks of an integrated circuit will be physically placed. 

  • A diagram, usually to scale, showing the layout of a building. 

undirected graph

noun
  • A graph in which the edges are not ordered, so the edge (a, b) is identical to the edge (b, a). 

How often have the words floor plan and undirected graph occurred in a corpus of books? (source: Google Ngram Viewer )