Differences between revisions 19 and 21 (spanning 2 versions)

Emily Kirkman is working on this project. [http://sage.math.washington.edu:9001/graph Back to main wiki.]

The goal of the Graph Generators Class is to implement constructors for many common graphs, as well as thorough docstrings that can be used for reference. The graph generators will grow as the Graph Theory Project does. So please check back for additions and feel free to leave requests in the suggestions section.

We currently have 54 constructors of named graphs and basic structures. Most of these graphs are constructed with a preset dictionary of x-y coordinates of each node. This is advantageous for both style and time. (The default graph plotting in SAGE uses the spring-layout algorithm). SAGE graphs all have an associated graphics object, and examples of plotting options are shown on the graphs below.

As we implement algorithms into the Graph Theory Package, the constructors of known graphs would set their properties upon instantiation as well. For example, if someone created a very large complete bipartite graph and then asked if it is a bipartite graph (not currently implemented), then instead of running through an algorithm to check it, we could return a value set at instantiation. Further, this will improve the reference use of the docstrings as we would list the properties of each named graph.

Due to the volume of graphs now in the generators class, this wiki page is now intended to give status updates and serve as a gallery of graphs currently implemented. To see information on a specific graph, run SAGE or the SAGE [http://sage.math.washington.edu:8100 notebook]. For a list of graph constructors, type "graphs." and hit tab. For docstrings, type the graph name and one question mark (i.e.: "graphs.CubeGraph?") then shift + enter. For source code, do likewise with two question marks.

TableOfContents

Suggestions

Graphs I Plan to Add

Inherited from NetworkX

Bipartite Generators
Grid (n-dim)
Sedgewick
Truncated cube
Truncated tetrahedron
Tutte

Families of Graphs

Generalized Petersen graphs
Petersen Graph family
Trees (Directed – not simple. Maybe Balanced tree constructor and query isTree)
Cayley (Requires Edge Coloring)
Paley

Named Graphs

Brinkman
Clebsch
Grötzsch graph
Tutte eight-cage
Szekeres snark
Thomassen graph
Johnson (maybe own class)
Turan

Gallery of Graph Generators in SAGE

Named Graphs

Chvatal Graph

sage: (graphs.ChvatalGraph()).show(figsize=[4,4], graph_border=True)

attachment:chvatal.png

Desargues Graph

sage: (graphs.DesarguesGraph()).show(figsize=[4,4], graph_border=True)

attachment:desargues.png

Flower Snark

sage: flower_snark = graphs.FlowerSnark()
sage: flower_snark.set_boundary([15,16,17,18,19])
sage: flower_snark.show(figsize=[4,4], graph_border=True)

attachment:flower.png

Frucht

sage: frucht = graphs.FruchtGraph()
sage: frucht.show(figsize=[4,4], graph_border=True)

attachment:frucht.png

Heawood

sage: heawood = graphs.HeawoodGraph()
sage: heawood.show(figsize=[4,4], graph_border=True)

attachment:heawood.png

Möbius Kantor

sage: moebius_kantor = graphs.MoebiusKantorGraph()
sage: moebius_kantor.show(figsize=[4,4], graph_border=True)

attachment:moebiuskantor.png

Pappus Graph

sage: (graphs.PappusGraph()).show(figsize=[4,4], graph_border=True)

attachment:pappus.png

Petersen

sage: petersen = graphs.PetersenGraph()
sage: petersen.show(figsize=[4,4], graph_border=True)

attachment:petersen.png

Thomsen

sage: thomsen = graphs.ThomsenGraph()
sage: thomsen.show(figsize=[4,4], graph_border=True)

attachment:thomsen.png

Graph Families

Complete Bipartite Graphs

sage: comp_bip_list = []
sage: for i in range (2):
... for j in range (4):
...  comp_bip_list.append(graphs.CompleteBipartiteGraph(i+3,j+1))
...
sage: graphs_list.show_graphs(comp_bip_list)

attachment:compbip.png

Complete Graphs

sage: comp_list = []
sage: for i in range(13)[1:]:
... comp_list.append(graphs.CompleteGraph(i))
...
sage: graphs_list.show_graphs(comp_list)

attachment:complete.png

Cube Graphs

sage: cube_list = []
sage: for i in range(6)[2:]:
... cube_list.append(graphs.CubeGraph(i))
...
sage: graphs_list.show_graphs(cube_list)

attachment:cube.png

sage: bigger_cube = graphs.CubeGraph(8)
sage: bigger_cube.show(figsize=[8,8], node_size=20, vertex_labels=False, graph_border=True)

attachment:biggercube.png

Balanced Tree

sage: (graphs.BalancedTree(3,5)).show(node_size=20, vertex_labels=False, figsize=[4,4], graph_border=True)

attachment:baltree.png

LCF Graph

sage: (graphs.LCFGraph(20, [-10,-7,-5,4,7,-10,-7,-4,5,7,-10,-7,6,-5,7,-10,-7,5,-6,7], 1)).show(figsize=[4,4], graph_border=True)

attachment:lcf.png

Platonic Solids

Tetrahedral Graph

sage: tetrahedral = graphs.TetrahedralGraph()
sage: tetrahedral.show(figsize=[4,4], graph_border=True)

attachment:tetrahedral.png

Hexahedral Graph

sage: (graphs.HexahedralGraph()).show(figsize=[4,4], graph_border=True)

attachment:hexahedral.png

Octahedral Graph

sage: octahedral = graphs.OctahedralGraph()
sage: octahedral.show(figsize=[4,4], vertex_labels=False, node_size=50, graph_border=True)

attachment:octahedral.png

Icosahedral Graph

sage: (graphs.IcosahedralGraph()).show(figsize=[4,4], graph_border=True)

attachment:icosahedral.png

Dodecahedral Graph

sage: dodecahedral = graphs.DodecahedralGraph()
sage: dodecahedral.show(figsize=[4,4], vertex_labels=False, node_size=50, graph_border=True)

attachment:dodecahedral.png

Pseudofractal Graphs

Dorogovtsev Goltsev Mendes Graph

sage: (graphs.DorogovtsevGoltsevMendesGraph(3)).show(figsize=[4,4], graph_border=True)

attachment:dorogovtsev.png

Basic Structures

Barbell Graph

sage: barbell_list = []
sage: for i in range (4):
... for j in range (2):
...  barbell_list.append(graphs.BarbellGraph(i+3, j+2))
...
sage: graphs_list.show_graphs(barbell_list)

attachment:barbell.png

Bull Graph

sage: bull = graphs.BullGraph()
sage: bull.show(figsize=[4,4], graph_border=True)

attachment:bull.png

Circular Ladder Graph

sage: circ_ladder = graphs.CircularLadderGraph(9)
sage: circ_ladder.show(figsize=[4,4], graph_border=True)

attachment:circladder.png

Claw Graph

sage: claw = graphs.ClawGraph()
sage: claw.show(figsize=[4,4], graph_border=True)

attachment:claw.png

Cycle Graphs

sage: cycle = graphs.CycleGraph(17)
sage: cycle.show(figsize=[4,4], graph_border=True)

attachment:cycle.png

Diamond Graph

sage: diamond = graphs.DiamondGraph()
sage: diamond.show(figsize=[4,4], graph_border=True)

attachment:diamond.png

Empty Graph

sage: empty = graphs.EmptyGraph()
sage: empty.show(figsize=[1,1], graph_border=True)

attachment:empty.png

Grid 2d Graph

sage: grid = graphs.Grid2dGraph(3,5)
sage: grid.show(figsize=[5,3])

attachment:grid.png

House Graph

sage: house = graphs.HouseGraph()
sage: house.show(figsize=[4,4], graph_border=True)

attachment:house.png

House X Graph

sage: houseX = graphs.HouseXGraph()
sage: houseX.show(figsize=[4,4], graph_border=True)

attachment:housex.png

Krackhardt Kite Graph

sage: krackhardt = graphs.KrackhardtKiteGraph()
sage: krackhardt.show(figsize=[4,4], graph_border=True)

attachment:krack.png

Ladder Graph

sage: ladder = graphs.LadderGraph(5)
sage: ladder.show(figsize=[4,4], graph_border=True)

attachment:ladder.png

Lollipop Graph

sage: lollipop_list = []
sage: for i in range (4):
... for j in range (2):
...  lollipop_list.append(graphs.LollipopGraph(i+3, j+2))
...
sage: graphs_list.show_graphs(lollipop_list)

attachment:lollipop.png

Path Graph

sage: path_line = graphs.PathGraph(5)
sage: path_circle = graphs.PathGraph(15)
sage: path_maze = graphs.PathGraph(45)
sage: path_list = [path_line, path_circle, path_maze]
sage: graphs_list.show_graphs(path_list)

attachment:path.png

Star Graph

sage: star_list = []
sage: for i in range (12)[4:]:
... star_list.append(graphs.StarGraph(i))
...
sage: graphs_list.show_graphs(star_list)

attachment:star.png

Wheel Graph

sage: wheel_list = []
sage: for i in range (12)[4:]:
... wheel_list.append(graphs.WheelGraph(i))
...
sage: graphs_list.show_graphs(wheel_list)

attachment:wheel.png

Random Generators

Random GNP

Use for dense graphs:

time
sage: (graphs.RandomGNP(16,.77)).show(figsize=[4,4], graph_border=True)

My results: CPU time: 0.74 s, Wall time: 0.73 s attachment:random.png

Random GNP Fast

Use for sparse graphs:

time
sage: (graphs.RandomGNPFast(16,.19)).show(figsize=[4,4], graph_border=True)

My results: CPU time: 0.63 s, Wall time: 0.62 s attachment:randomfast.png

Random Barabasi Albert

sage: (graphs.RandomBarabasiAlbert(7,3)).show(figsize=[4,4], graph_border=True)

attachment:barabasi.png

Random GNM

sage: (graphs.RandomGNM(7,16)).show(figsize=[4,4], graph_border=True)

attachment:gnm.png

Random Newman Watts Strogatz

sage: (graphs.RandomNewmanWattsStrogatz(7,3,.5)).show(figsize=[4,4], graph_border=True)

attachment:newman.png

Random Holme Kim

sage: (graphs.RandomHolmeKim(12,3,.4)).show(figsize=[4,4], graph_border=True)

attachment:holme.png

Random Lobster

sage: (graphs.RandomHolmeKim(12,3,.4)).show(figsize=[4,4], graph_border=True)

attachment:lobster.png

Random Tree Powerlaw

sage: (graphs.RandomTreePowerlaw(15)).show(figsize=[4,4], graph_border=True)

attachment:powerlaw.png

Random Regular

sage: (graphs.RandomRegular(3,20)).show(node_size=20, vertex_labels=False, figsize=[4,4], graph_border=True)

attachment:randreg.png

Random Shell

sage: (graphs.RandomShell([(10,20,0.8),(20,40,0.8)])).show(node_size=20, vertex_labels=False, figsize=[4,4], graph_border=True)

attachment:shell.png

Random Directed Graphs

Random Directed GN

sage: (graphs.RandomDirectedGN(12)).show(node_size=20, vertex_labels=False, figsize=[4,4], graph_border=True)

attachment:randdirgn.png

Random Directed GNC

sage: (graphs.RandomDirectedGNC(12)).show(node_size=20, vertex_labels=False, figsize=[4,4], graph_border=True)

attachment:randdirgnc.png

Random Directed GNR

sage: (graphs.RandomDirectedGNR(12,.15)).show(node_size=20, vertex_labels=False, figsize=[4,4], graph_border=True)

attachment:randdirgnr.png

Graphs With a Given Degree Sequence

Degree Sequence

sage: (graphs.DegreeSequence([3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3])).show(vertex_labels=False, node_size=30, figsize=[4,4], graph_border=True)

attachment:degseq.png

Degree Sequence Configuration Model

sage: (graphs.DegreeSequenceConfigurationModel([3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3])).show(vertex_labels=False, node_size=30, figsize=[4,4], graph_border=True)

attachment:degseqconf.png

Degree Sequence Tree

sage: (graphs.DegreeSequenceTree([3,1,3,3,1,1,1,2,1])).show(figsize=[4,4], graph_border=True)

attachment:degseqtree.png

Degree Sequence Expected

sage: (graphs.DegreeSequenceExpected([1,2,3,2,3])).show(figsize=[4,4],graph_border=True)

attachment:degseqexp.png

-  ⇤ ← Revision 19 as of 2007-06-12 21:12:12 → 
  Size: 9244
  Editor: anonymous
  Comment:
+   ← Revision 21 as of 2007-06-12 22:37:08 → ⇥
  Size: 12090
  Editor: anonymous
  Comment:
-Deletions are marked like this.
+Additions are marked like this.
 Line 5:
-We currently have 30 constructors of named graphs and basic structures.  Most of these graphs are constructed with a preset dictionary of x-y coordinates of each node.  This is advantageous for both style and time.  (The default graph plotting in SAGE uses the spring-layout algorithm).  SAGE graphs all have an associated graphics object, and examples of plotting options are shown on the graphs below.
+We currently have 54 constructors of named graphs and basic structures.  Most of these graphs are constructed with a preset dictionary of x-y coordinates of each node.  This is advantageous for both style and time.  (The default graph plotting in SAGE uses the spring-layout algorithm).  SAGE graphs all have an associated graphics object, and examples of plotting options are shown on the graphs below.
 Line 20:
- * Balanced tree
 * Dorogovstev golstev mendes graph
-Line 23:
+Line 21:
- * Chvatal
 * Desargues
 * Pappus
-Line 30:
+Line 25:
- * Also many more random generators and gens from degree sequence to sort through
-Line 42:
+Line 36:
- * Icosahedron
-Line 55:
+Line 48:
+{{{
sage: (graphs.ChvatalGraph()).show(figsize=[4,4], graph_border=True)
}}}
attachment:chvatal.png
-Line 57:
+Line 54:
+{{{
sage: (graphs.DesarguesGraph()).show(figsize=[4,4], graph_border=True)
}}}
attachment:desargues.png
-Line 80:
+Line 81:
 Line 89:
+{{{
sage: (graphs.PappusGraph()).show(figsize=[4,4], graph_border=True)
}}}
attachment:pappus.png
-Line 144:
+Line 148:
+{{{
sage: (graphs.BalancedTree(3,5)).show(node_size=20, vertex_labels=False, figsize=[4,4], graph_border=True)
}}}
attachment:baltree.png
-Line 146:
+Line 154:
+{{{
sage: (graphs.LCFGraph(20, [-10,-7,-5,4,7,-10,-7,-4,5,7,-10,-7,6,-5,7,-10,-7,5,-6,7], 1)).show(figsize=[4,4], graph_border=True)
}}}
attachment:lcf.png
-Line 157:
+Line 169:
+{{{
sage: (graphs.HexahedralGraph()).show(figsize=[4,4], graph_border=True)
}}}
attachment:hexahedral.png
-Line 166:
+Line 182:
+{{{
sage: (graphs.IcosahedralGraph()).show(figsize=[4,4], graph_border=True)
}}}
attachment:icosahedral.png
-Line 177:
+Line 197:
+{{{
sage: (graphs.DorogovtsevGoltsevMendesGraph(3)).show(figsize=[4,4], graph_border=True)
}}}
attachment:dorogovtsev.png
-Line 332:
+Line 356:
+{{{
sage: (graphs.RandomBarabasiAlbert(7,3)).show(figsize=[4,4], graph_border=True)
}}}
attachment:barabasi.png
-Line 334:
+Line 362:
-=== Random Neewman Watts Strogatz ===
+{{{
sage: (graphs.RandomGNM(7,16)).show(figsize=[4,4], graph_border=True)
}}}
attachment:gnm.png

=== Random Newman Watts Strogatz ===
{{{
sage: (graphs.RandomNewmanWattsStrogatz(7,3,.5)).show(figsize=[4,4], graph_border=True)
}}}
attachment:newman.png
-Line 338:
+Line 374:
+{{{
sage: (graphs.RandomHolmeKim(12,3,.4)).show(figsize=[4,4], graph_border=True)
}}}
attachment:holme.png
-Line 340:
+Line 380:
+{{{
sage: (graphs.RandomHolmeKim(12,3,.4)).show(figsize=[4,4], graph_border=True)
}}}
attachment:lobster.png
-Line 342:
+Line 386:
+{{{
sage: (graphs.RandomTreePowerlaw(15)).show(figsize=[4,4], graph_border=True)
}}}
attachment:powerlaw.png
-Line 344:
+Line 392:
+{{{
sage: (graphs.RandomRegular(3,20)).show(node_size=20, vertex_labels=False, figsize=[4,4], graph_border=True)
}}}
attachment:randreg.png
-Line 346:
+Line 398:
+{{{
sage: (graphs.RandomShell([(10,20,0.8),(20,40,0.8)])).show(node_size=20, vertex_labels=False, figsize=[4,4], graph_border=True)
}}}
attachment:shell.png
-Line 350:
+Line 406:
+{{{
sage: (graphs.RandomDirectedGN(12)).show(node_size=20, vertex_labels=False, figsize=[4,4], graph_border=True)
}}}
attachment:randdirgn.png
-Line 352:
+Line 412:
+{{{
sage: (graphs.RandomDirectedGNC(12)).show(node_size=20, vertex_labels=False, figsize=[4,4], graph_border=True)
}}}
attachment:randdirgnc.png
-Line 354:
+Line 418:
+{{{
sage: (graphs.RandomDirectedGNR(12,.15)).show(node_size=20, vertex_labels=False, figsize=[4,4], graph_border=True)
}}}
attachment:randdirgnr.png
-Line 358:
+Line 426:
+{{{
sage: (graphs.DegreeSequence([3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3])).show(vertex_labels=False, node_size=30, figsize=[4,4], graph_border=True)
}}}
attachment:degseq.png
-Line 360:
+Line 432:
+{{{
sage: (graphs.DegreeSequenceConfigurationModel([3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3])).show(vertex_labels=False, node_size=30, figsize=[4,4], graph_border=True)
}}}
attachment:degseqconf.png
-Line 362:
+Line 438:
+{{{
sage: (graphs.DegreeSequenceTree([3,1,3,3,1,1,1,2,1])).show(figsize=[4,4], graph_border=True)
}}}
attachment:degseqtree.png
-Line 364:
+Line 444:
+{{{
sage: (graphs.DegreeSequenceExpected([1,2,3,2,3])).show(figsize=[4,4],graph_border=True)
}}}
attachment:degseqexp.png

Diff for "graph_generators"

Suggestions

Graphs I Plan to Add

Inherited from NetworkX

Families of Graphs

Named Graphs

Gallery of Graph Generators in SAGE

Named Graphs

Chvatal Graph

Desargues Graph

Flower Snark

Frucht

Heawood

Möbius Kantor

Pappus Graph

Petersen

Thomsen

Graph Families

Complete Bipartite Graphs

Complete Graphs

Cube Graphs

Balanced Tree

LCF Graph

Platonic Solids

Tetrahedral Graph

Hexahedral Graph

Octahedral Graph

Icosahedral Graph

Dodecahedral Graph

Pseudofractal Graphs

Dorogovtsev Goltsev Mendes Graph

Basic Structures

Barbell Graph

Bull Graph

Circular Ladder Graph

Claw Graph

Cycle Graphs

Diamond Graph

Empty Graph

Grid 2d Graph

House Graph

House X Graph

Krackhardt Kite Graph

Ladder Graph

Lollipop Graph

Path Graph

Star Graph

Wheel Graph

Random Generators

Random GNP

Random GNP Fast

Random Barabasi Albert

Random GNM

Random Newman Watts Strogatz

Random Holme Kim

Random Lobster

Random Tree Powerlaw

Random Regular

Random Shell

Random Directed Graphs

Random Directed GN

Random Directed GNC

Random Directed GNR

Graphs With a Given Degree Sequence

Degree Sequence

Degree Sequence Configuration Model

Degree Sequence Tree

Degree Sequence Expected