The Cayley graph for
sage: G = sage.groups.perm_gps.permgroup.AlternatingGroup(5) sage: C = G.cayley_graph() sage: C.show3d(bgcolor=(0,0,0), arc_color=(1,1,1), vertex_size=0.02, arc_size=0.007, arc_size2=0.01, xres=1000, yres=800, iterations=200)
attachment:A5.jpg
Emily Kirkman and Robert Miller are working on this project. [http://wiki.sagemath.org/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.
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(5)).show(figsize=[4,4], graph_border=True, vertex_size=10, vertex_labels=False)
attachment:tmp_6.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