the book embedding problem from a sat solving perspective
play

The Book Embedding Problem from a SAT-Solving Perspective [GD 2015] - PowerPoint PPT Presentation

The Book Embedding Problem from a SAT-Solving Perspective [GD 2015] Michalis Bekos, Michael Kaufmann, Christian Zielke Universit at T ubingen, Germany The Book Embedding problem Vertices V ordered, on a spine Edges E assigned


  1. SAT formulation General idea: build formula F ( G , p ) via � 1. 1. ensure a proper order of the vertices on the spine σ ( v i , v j ) v i v j � 2. 2. assure that every edge is assigned to one of p pages e i e j χ ( e i , e j ) 3. 3. forbid crossings on each page e i e j forbid χ ( e i , e j ) together with

  2. SAT formulation General idea: build formula F ( G , p ) via � 1. 1. ensure a proper order of the vertices on the spine σ ( v i , v j ) v i v j � 2. 2. assure that every edge is assigned to one of p pages e i e j χ ( e i , e j ) 3. 3. forbid crossings on each page e i e j forbid χ ( e i , e j ) together with σ ( v i , v k ), σ ( v k , v j ), σ ( v j , v l ) v i v k v j v l

  3. SAT formulation General idea: build formula F ( G , p ) via � 1. 1. ensure a proper order of the vertices on the spine σ ( v i , v j ) v i v j � 2. 2. assure that every edge is assigned to one of p pages e i e j χ ( e i , e j ) � 3. 3. forbid crossings on each page e i e j forbid χ ( e i , e j ) together with σ ( v i , v k ), σ ( v k , v j ), σ ( v j , v l ) v i v k v j v l (for every pair of edges 8 forbidden configurations)

  4. SAT formulation General idea: build formula F ( G , p ) via � 1. 1. ensure a proper order of the vertices on the spine σ ( v i , v j ) v i v j � 2. 2. assure that every edge is assigned to one of p pages e i e j χ ( e i , e j ) � 3. 3. forbid crossings on each page solve optimization problem: F ( G , k − 1) is UNSAT , F ( G , k ) is SAT

  5. Experiments Setup: all Rome and North graphs (taken from www.graphdrawing.org)

  6. Experiments Setup: all Rome and North graphs (taken from www.graphdrawing.org) Timeout: 1200 sec

  7. Experiments Setup: all Rome and North graphs (taken from www.graphdrawing.org) Timeout: 1200 sec Rome graphs planar: 3281 nonplanar: 8253 (graphs are very sparse: 0.069)

  8. Experiments Setup: all Rome and North graphs (taken from www.graphdrawing.org) Timeout: 1200 sec Rome graphs planar: 3281 all fit in 2 pages nonplanar: 8253 all fit in 3 pages (graphs are very sparse: 0.069)

  9. Experiments Setup: all Rome and North graphs (taken from www.graphdrawing.org) Timeout: 1200 sec Rome graphs planar: 3281 all fit in 2 pages nonplanar: 8253 all fit in 3 pages (graphs are very sparse: 0.069) North graphs planar: 854 nonplanar: 423 (graphs are denser: 0.13)

  10. Experiments Setup: all Rome and North graphs (taken from www.graphdrawing.org) Timeout: 1200 sec Rome graphs planar: 3281 all fit in 2 pages nonplanar: 8253 all fit in 3 pages (graphs are very sparse: 0.069) North graphs planar: 854 all fit in 2 pages nonplanar: 423 only 344 were solved completely (graphs are denser: 0.13)

  11. Experiments Setup: all Rome and North graphs (taken from www.graphdrawing.org) Timeout: 1200 sec Rome graphs planar: 3281 all fit in 2 pages nonplanar: 8253 all fit in 3 pages (graphs are very sparse: 0.069) North graphs planar: 854 all fit in 2 pages nonplanar: 423 only 344 were solved completely (some graphs have high book thickness) (graphs are denser: 0.13)

  12. Experiments Hypothesis: There is a (maximal) planar graph whose book thickness is 4.

  13. Experiments Hypothesis: There is a (maximal) planar graph whose book thickness is 4. Setup: several maximal planar graphs with 500-700 vertices

  14. Experiments Hypothesis: There is a (maximal) planar graph whose book thickness is 4. Setup: several maximal planar graphs with 500-700 vertices Construction: 1. triangulated graph as base (”skeleton”) 1. (not necessarily non-Hamiltonian)

  15. Experiments Hypothesis: There is a (maximal) planar graph whose book thickness is 4. Setup: several maximal planar graphs with 500-700 vertices Construction: 1. 1. triangulated graph as base (”skeleton”) (not necessarily non-Hamiltonian) 2. 2. augmenting the faces of the base graph by a combination of Stellation Octahedron Creation Graph Insertion

  16. Experiments Hypothesis: There is a (maximal) planar graph whose book thickness is 4. Setup: several maximal planar graphs with 500-700 vertices Construction: 1. 1. triangulated graph as base (”skeleton”) (not necessarily non-Hamiltonian) 2. 2. augmenting the faces of the base graph by a combination of Stellation Octahedron Creation Graph Insertion

  17. Experiments Hypothesis: There is a (maximal) planar graph whose book thickness is 4. Setup: several maximal planar graphs with 500-700 vertices Construction: 1. 1. triangulated graph as base (”skeleton”) (not necessarily non-Hamiltonian) 2. 2. augmenting the faces of the base graph by a combination of Stellation Octahedron Creation Graph Insertion

  18. Experiments Hypothesis: There is a (maximal) planar graph whose book thickness is 4. Setup: several maximal planar graphs with 500-700 vertices Construction: 1. 1. triangulated graph as base (”skeleton”) (not necessarily non-Hamiltonian) 2. 2. augmenting the faces of the base graph by a combination of Stellation Octahedron Creation Graph Insertion

  19. Experiments Hypothesis: There is a (maximal) planar graph whose book thickness is 4. Setup: several maximal planar graphs with 500-700 vertices Construction: 1. 1. triangulated graph as base (”skeleton”) (not necessarily non-Hamiltonian) 2. 2. augmenting the faces of the base graph by a combination of Stellation Octahedron Creation Graph Insertion

  20. Experiments Hypothesis: There is a (maximal) planar graph whose book thickness is 4. Setup: several maximal planar graphs with 500-700 vertices Construction: 1. 1. triangulated graph as base (”skeleton”) (not necessarily non-Hamiltonian) 2. 2. augmenting the faces of the base graph by a combination of Stellation Octahedron Creation Graph Insertion

  21. Experiments Hypothesis: There is a (maximal) planar graph whose book thickness is 4. Setup: several maximal planar graphs with 500-700 vertices Construction: 1. 1. triangulated graph as base (”skeleton”) (not necessarily non-Hamiltonian) 2. 2. augmenting the faces of the base graph by a combination of Stellation Octahedron Creation Graph Insertion

  22. Experiments Hypothesis: There is a (maximal) planar graph whose book thickness is 4. Setup: several maximal planar graphs with 500-700 vertices Construction: 1. 1. triangulated graph as base (”skeleton”) (not necessarily non-Hamiltonian) 2. 2. augmenting the faces of the base graph by a combination of Stellation Octahedron Creation Graph Insertion

  23. Experiments Hypothesis: There is a (maximal) planar graph whose book thickness is 4. Setup: several maximal planar graphs with 500-700 vertices (all 3 page embeddable) Construction: 1. 1. triangulated graph as base (”skeleton”) (not necessarily non-Hamiltonian) 2. 2. augmenting the faces of the base graph by a combination of Stellation Octahedron Creation Graph Insertion

  24. Experiments - Idea: possibly overcome the limit of ≈ 700 vertices

  25. Experiments - Idea: possibly overcome the limit of ≈ 700 vertices Hypotheses: There is a maximal planar graph G a that has at least one face f a whose edges cannot be on the same page in any book embedding on 3 pages.

  26. Experiments - Idea: possibly overcome the limit of ≈ 700 vertices Hypotheses: There is a maximal planar graph G a that has at least one face f a whose edges cannot be on the same page in any book embedding on 3 pages. test F ( G a , 3) ∪ { ( χ ( e i , e j ) ∧ χ ( e i , e k ) } ∀ f a = ( e i , e j , e k ) ∈ G a

  27. Experiments - Idea: possibly overcome the limit of ≈ 700 vertices Hypotheses: There is a maximal planar graph G a that has at least one face f a whose edges cannot be on the same page in any book embedding on 3 pages. test F ( G a , 3) ∪ { ( χ ( e i , e j ) ∧ χ ( e i , e k ) } ∀ f a = ( e i , e j , e k ) ∈ G a There is a maximal planar graph G c that has at least one face f c whose edges are on the same page in any book embedding on 3 pages.

  28. Experiments - Idea: possibly overcome the limit of ≈ 700 vertices Hypotheses: There is a maximal planar graph G a that has at least one face f a whose edges cannot be on the same page in any book embedding on 3 pages. test F ( G a , 3) ∪ { ( χ ( e i , e j ) ∧ χ ( e i , e k ) } ∀ f a = ( e i , e j , e k ) ∈ G a There is a maximal planar graph G c that has at least one face f c whose edges are on the same page in any book embedding on 3 pages. ∀ f c = ( e i , e j , e k ) ∈ G c test F ( G c , 3) ∪ ( ¬ χ ( e i , e j ) ∨ ¬ χ ( e i , e k ))

  29. Experiments - Idea: possibly overcome the limit of ≈ 700 vertices Hypotheses: There is a maximal planar graph G a that has at least one face f a whose edges cannot be on the same page in any book embedding on 3 pages. test F ( G a , 3) ∪ { ( χ ( e i , e j ) ∧ χ ( e i , e k ) } ∀ f a = ( e i , e j , e k ) ∈ G a There is a maximal planar graph G c that has at least one face f c whose edges are on the same page in any book embedding on 3 pages. ∀ f c = ( e i , e j , e k ) ∈ G c test F ( G c , 3) ∪ ( ¬ χ ( e i , e j ) ∨ ¬ χ ( e i , e k )) G c

  30. Experiments - Idea: possibly overcome the limit of ≈ 700 vertices Hypotheses: There is a maximal planar graph G a that has at least one face f a whose edges cannot be on the same page in any book embedding on 3 pages. test F ( G a , 3) ∪ { ( χ ( e i , e j ) ∧ χ ( e i , e k ) } ∀ f a = ( e i , e j , e k ) ∈ G a There is a maximal planar graph G c that has at least one face f c whose edges are on the same page in any book embedding on 3 pages. ∀ f c = ( e i , e j , e k ) ∈ G c test F ( G c , 3) ∪ ( ¬ χ ( e i , e j ) ∨ ¬ χ ( e i , e k )) f a is outer face G a G c

  31. Experiments - Idea: possibly overcome the limit of ≈ 700 vertices Hypotheses: There is a maximal planar graph G a that has at least one face f a whose edges cannot be on the same page in any book embedding on 3 pages. test F ( G a , 3) ∪ { ( χ ( e i , e j ) ∧ χ ( e i , e k ) } ∀ f a = ( e i , e j , e k ) ∈ G a There is a maximal planar graph G c that has at least one face f c whose edges are on the same page in any book embedding on 3 pages. ∀ f c = ( e i , e j , e k ) ∈ G c test F ( G c , 3) ∪ ( ¬ χ ( e i , e j ) ∨ ¬ χ ( e i , e k )) G a G a G c

  32. Experiments - Idea: possibly overcome the limit of ≈ 700 vertices Hypotheses: There is a maximal planar graph G a that has at least one face f a whose edges cannot be on the same page in any book embedding on 3 pages. test F ( G a , 3) ∪ { ( χ ( e i , e j ) ∧ χ ( e i , e k ) } ∀ f a = ( e i , e j , e k ) ∈ G a There is a maximal planar graph G c that has at least one face f c whose edges are on the same page in any book embedding on 3 pages. ∀ f c = ( e i , e j , e k ) ∈ G c test F ( G c , 3) ∪ ( ¬ χ ( e i , e j ) ∨ ¬ χ ( e i , e k )) G a tested ≈ 284,000 graphs G a G c with 60 to 125 vertices → 0 confirmed Hypotheses

  33. Experiments Hypothesis: There is a 1-planar graph whose book thickness is (at least) 4.

  34. Experiments Hypothesis: There is a 1-planar graph whose book thickness is (at least) 4. 5 8 1 4 2 3 6 7

  35. Experiments Hypothesis: There is a 1-planar graph whose book thickness is (at least) 4. 5 8 1 4 1 5 4 2 7 3 8 6 2 3 6 7

  36. Experiments Hypothesis: There is a 1-planar graph whose book thickness is (at least) 5.

  37. Experiments Hypothesis: There is a 1-planar graph whose book thickness is (at least) 5. Setup: all 2,098,675 planar quadrangulations with 25 vertices triconnected; min degree 3 → augment every face with two crossing edges

  38. Experiments Hypothesis: There is a 1-planar graph whose book thickness is (at least) 5. Setup: all 2,098,675 planar quadrangulations with 25 vertices (all 4 page embeddable) triconnected; min degree 3 → augment every face with two crossing edges

  39. Experiments Hypothesis: There is a 1-planar graph whose book thickness is (at least) 5. Setup: all 2,098,675 planar quadrangulations with 25 vertices (all 4 page embeddable) triconnected; min degree 3 → augment every face with two crossing edges

  40. Experiments Hypothesis: There is a 1-planar graph whose book thickness is (at least) 5. Setup: all 2,098,675 planar quadrangulations with 25 vertices (all 4 page embeddable) triconnected; min degree 3 → augment every face with two crossing edges 8312 random optimal 1-planar graphs with 50 − 155 vertices (all 4 page embeddable)

  41. Experiments Hypothesis: There is a 1-planar graph whose book thickness is (at least) 5. Setup: all 2,098,675 planar quadrangulations with 25 vertices (all 4 page embeddable) triconnected; min degree 3 → augment every face with two crossing edges 8312 random optimal 1-planar graphs with 50 − 155 vertices (all 4 page embeddable)

  42. Experiments Hypothesis: There is a (maximal) planar graph, which cannot be embedded in a book of 3 pages, if the subgraphs at each page must be acyclic.

  43. Experiments Hypothesis: There is a (maximal) planar graph, which cannot be embedded in a book of 3 pages, if the subgraphs at each page must be acyclic. (Heath used that for proving book thickness of 3 for planar 3-trees)

  44. Experiments Hypothesis: There is a (maximal) planar graph, which cannot be embedded in a book of 3 pages, if the subgraphs at each page must be acyclic. (Heath used that for proving book thickness of 3 for planar 3-trees) Setup: tested over 15,000 maximal planar graphs with 25 to 80 vertices

  45. Experiments Hypothesis: There is a (maximal) planar graph, which cannot be embedded in a book of 3 pages, if the subgraphs at each page must be acyclic. (Heath used that for proving book thickness of 3 for planar 3-trees) Setup: tested over 15,000 maximal planar graphs with 25 to 80 vertices Timeout: 1200 sec 70.78 % of graphs were solved ≤ 3 minutes 76.37 % of graphs were solved ≤ 20 minutes

  46. Experiments Hypothesis: There is a (maximal) planar graph, which cannot be embedded in a book of 3 pages, if the subgraphs at each page must be acyclic. (Heath used that for proving book thickness of 3 for planar 3-trees) Setup: tested over 15,000 maximal planar graphs with 25 to 80 vertices Timeout: 1200 sec 70.78 % of graphs were solved ≤ 3 minutes 76.37 % of graphs were solved ≤ 20 minutes → additional constraints to force acyclic subgraphs increase runtime

  47. Experiments Hypothesis: (weaker) There is a (maximal) planar graph, which cannot be embedded in a book of 3 pages, if the subgraphs at each page must be acyclic. subgraphs are trees on n − 1 vertices vertices not spanned by trees build a face (w.l.o.g. outer face)

  48. Experiments Hypothesis: (weaker) There is a (maximal) planar graph, which cannot be embedded in a book of 3 pages, if the subgraphs at each page must be acyclic. 16 subgraphs are trees on n − 1 vertices vertices not spanned by trees 15 build a face (w.l.o.g. outer face) 14 12 11 13 9 10 7 8 6 5 3 4 1 2

  49. Experiments Hypothesis: (weaker) There is a (maximal) planar graph, which cannot be embedded in a book of 3 pages, if the subgraphs at each page must be acyclic. 16 subgraphs are trees on n − 1 vertices vertices not spanned by trees 15 build a face (w.l.o.g. outer face) 14 12 11 13 9 → Schnyder decomposition 10 not always possible 7 8 6 5 3 4 1 2

  50. Open problems All Hypothesis are unproven!

  51. Open problems All Hypothesis are unproven! - 1: (maximal) planar graph that requires 4 pages

  52. Open problems All Hypothesis are unproven! - 1: (maximal) planar graph that requires 4 pages - 1a: (maximal) planar graph that requires unicolored face

  53. Open problems All Hypothesis are unproven! - 1: (maximal) planar graph that requires 4 pages - 1a: (maximal) planar graph that requires unicolored face - 1b: (maximal) planar graph that cannot have a unicolored face

  54. Open problems All Hypothesis are unproven! - 1: (maximal) planar graph that requires 4 pages - 1a: (maximal) planar graph that requires unicolored face - 1b: (maximal) planar graph that cannot have a unicolored face - 2: 1-planar graph that requires 5 pages

  55. Open problems All Hypothesis are unproven! - 1: (maximal) planar graph that requires 4 pages - 1a: (maximal) planar graph that requires unicolored face - 1b: (maximal) planar graph that cannot have a unicolored face - 2: 1-planar graph that requires 5 pages - 3: (maximal) planar graph, that requires cyclic subgraphs on pages

  56. Open problems All Hypothesis are unproven! - 1: (maximal) planar graph that requires 4 pages - 1a: (maximal) planar graph that requires unicolored face - 1b: (maximal) planar graph that cannot have a unicolored face - 2: 1-planar graph that requires 5 pages - 3: (maximal) planar graph, that requires cyclic subgraphs on pages Improve the Encoding!

  57. Open problems All Hypothesis are unproven! - 1: (maximal) planar graph that requires 4 pages - 1a: (maximal) planar graph that requires unicolored face - 1b: (maximal) planar graph that cannot have a unicolored face - 2: 1-planar graph that requires 5 pages - 3: (maximal) planar graph, that requires cyclic subgraphs on pages Improve the Encoding! - cope with graphs, that have a high number of vertices and edges

  58. Open problems All Hypothesis are unproven! - 1: (maximal) planar graph that requires 4 pages - 1a: (maximal) planar graph that requires unicolored face - 1b: (maximal) planar graph that cannot have a unicolored face - 2: 1-planar graph that requires 5 pages - 3: (maximal) planar graph, that requires cyclic subgraphs on pages Improve the Encoding! - cope with graphs, that have a high number of vertices and edges - cope with graphs, that have high book thickness

  59. Open problems All Hypothesis are unproven! - 1: (maximal) planar graph that requires 4 pages - 1a: (maximal) planar graph that requires unicolored face - 1b: (maximal) planar graph that cannot have a unicolored face - 2: 1-planar graph that requires 5 pages - 3: (maximal) planar graph, that requires cyclic subgraphs on pages Improve the Encoding! - cope with graphs, that have a high number of vertices and edges - cope with graphs, that have high book thickness Thanks!!!

  60. Random Graph Creation

  61. Random Graph Creation

  62. Random Graph Creation left-to-right sorting

  63. Random Graph Creation left-to-right sorting

  64. Random Graph Creation left-to-right sorting

  65. Random Graph Creation left-to-right sorting

  66. Random Graph Creation left-to-right sorting

  67. Random Graph Creation

Download Presentation
Download Policy: The content available on the website is offered to you 'AS IS' for your personal information and use only. It cannot be commercialized, licensed, or distributed on other websites without prior consent from the author. To download a presentation, simply click this link. If you encounter any difficulties during the download process, it's possible that the publisher has removed the file from their server.

Recommend


More recommend