Graph plotting¶

(For LaTeX drawings of graphs, see the graph_latex module.)

All graphs have an associated Sage graphics object, which you can display:

Sage

sage: G = graphs.WheelGraph(15)
sage: P = G.plot()
sage: P.show()  # long time

Python

>>> from sage.all import *
>>> G = graphs.WheelGraph(Integer(15))
>>> P = G.plot()
>>> P.show()  # long time

When plotting a graph created using Sage’s Graph command, node positions are determined using the spring-layout algorithm. Special graphs available from graphs.* have preset positions. For example, compare the two plots of the Petersen graph, as obtained using Graph or as obtained from that database:

Sage

sage: petersen_spring = Graph(':I`ES@obGkqegW~')
sage: petersen_spring.show()  # long time

Python

>>> from sage.all import *
>>> petersen_spring = Graph(':I`ES@obGkqegW~')
>>> petersen_spring.show()  # long time

Sage

sage: petersen_database = graphs.PetersenGraph()
sage: petersen_database.show()  # long time

Python

>>> from sage.all import *
>>> petersen_database = graphs.PetersenGraph()
>>> petersen_database.show()  # long time

All constructors in this database (except some random graphs) prefill the position dictionary, bypassing the spring-layout positioning algorithm.

Plot options

Here is the list of options accepted by plot() and the constructor of GraphPlot. Those two functions also accept all options of sage.plot.graphics.Graphics.show().

`layout`	A layout algorithm – one of : “acyclic”, “circular” (plots the graph with vertices evenly distributed on a circle), “ranked”, “graphviz”, “planar”, “spring” (traditional spring layout, using the graph’s current positions as initial positions), or “tree” (the tree will be plotted in levels, depending on minimum distance for the root).
`iterations`	The number of times to execute the spring layout algorithm.
`heights`	A dictionary mapping heights to the list of vertices at this height.
`spring`	Use spring layout to finalize the current layout.
`tree_root`	A vertex designation for drawing trees. A vertex of the tree to be used as the root for the `layout='tree'` option. If no root is specified, then one is chosen close to the center of the tree. Ignored unless `layout='tree'`.
`forest_roots`	An iterable specifying which vertices to use as roots for the `layout='forest'` option. If no root is specified for a tree, then one is chosen close to the center of the tree. Ignored unless `layout='forest'`.
`tree_orientation`	The direction of tree branches – ‘up’, ‘down’, ‘left’ or ‘right’.
`save_pos`	Whether or not to save the computed position for the graph.
`dim`	The dimension of the layout – 2 or 3.
`prog`	Which graphviz layout program to use – one of “circo”, “dot”, “fdp”, “neato”, or “twopi”.
`by_component`	Whether to do the spring layout by connected component – boolean.
`pos`	The position dictionary of vertices.
`vertex_labels`	Vertex labels to draw. This can be `True`/`False` to indicate whether to print the vertex string representation of not, a dictionary keyed by vertices and associating to each vertex a label string, or a function taking as input a vertex and returning a label string.
`vertex_color`	Default color for vertices not listed in vertex_colors dictionary.
`vertex_colors`	A dictionary specifying vertex colors: each key is a color recognizable by matplotlib, and each corresponding value is a list of vertices.
`vertex_size`	The size to draw the vertices.
`vertex_shape`	The shape to draw the vertices. Currently unavailable for Multi-edged DiGraphs.
`edge_labels`	Whether or not to draw edge labels.
`edge_style`	The linestyle of the edges. It should be one of “solid”, “dashed”, “dotted”, dashdot”, or “-”, “–”, “:”, “-.”, respectively.
`edge_thickness`	The thickness of the edges.
`edge_color`	The default color for edges not listed in edge_colors.
`edge_colors`	A dictionary specifying edge colors: each key is a color recognized by matplotlib, and each corresponding value is a list of edges.
`color_by_label`	Whether to color the edges according to their labels. This also accepts a function or dictionary mapping labels to colors.
`partition`	A partition of the vertex set. If specified, plot will show each cell in a different color; vertex_colors takes precedence.
`loop_size`	The radius of the smallest loop.
`dist`	The distance between multiedges.
`max_dist`	The max distance range to allow multiedges.
`talk`	Whether to display the vertices in talk mode (larger and white).
`graph_border`	Whether or not to draw a frame around the graph.
`edge_labels_background`	The color of the background of the edge labels.

Default options

This module defines two dictionaries containing default options for the plot() and show() methods. These two dictionaries are sage.graphs.graph_plot.DEFAULT_PLOT_OPTIONS and sage.graphs.graph_plot.DEFAULT_SHOW_OPTIONS, respectively.

Obviously, these values are overruled when arguments are given explicitly.

Here is how to define the default size of a graph drawing to be (6, 6). The first two calls to show() use this option, while the third does not (a value for figsize is explicitly given):

Sage

sage: import sage.graphs.graph_plot
sage: sage.graphs.graph_plot.DEFAULT_SHOW_OPTIONS['figsize'] = (6, 6)
sage: graphs.PetersenGraph().show()  # long time
sage: graphs.ChvatalGraph().show()  # long time
sage: graphs.PetersenGraph().show(figsize=(4, 4))  # long time

Python

>>> from sage.all import *
>>> import sage.graphs.graph_plot
>>> sage.graphs.graph_plot.DEFAULT_SHOW_OPTIONS['figsize'] = (Integer(6), Integer(6))
>>> graphs.PetersenGraph().show()  # long time
>>> graphs.ChvatalGraph().show()  # long time
>>> graphs.PetersenGraph().show(figsize=(Integer(4), Integer(4)))  # long time

We can now reset the default to its initial value, and now display graphs as previously:

Sage

sage: sage.graphs.graph_plot.DEFAULT_SHOW_OPTIONS['figsize'] = (4, 4)
sage: graphs.PetersenGraph().show()  # long time
sage: graphs.ChvatalGraph().show()  # long time

Python

>>> from sage.all import *
>>> sage.graphs.graph_plot.DEFAULT_SHOW_OPTIONS['figsize'] = (Integer(4), Integer(4))
>>> graphs.PetersenGraph().show()  # long time
>>> graphs.ChvatalGraph().show()  # long time

Note

While DEFAULT_PLOT_OPTIONS affects both G.show() and G.plot(), settings from DEFAULT_SHOW_OPTIONS only affects G.show().

In order to define a default value permanently, you can add a couple of lines to Sage’s startup scripts. Example:

Sage

sage: import sage.graphs.graph_plot
sage: sage.graphs.graph_plot.DEFAULT_SHOW_OPTIONS['figsize'] = (4, 4)

Python

>>> from sage.all import *
>>> import sage.graphs.graph_plot
>>> sage.graphs.graph_plot.DEFAULT_SHOW_OPTIONS['figsize'] = (Integer(4), Integer(4))

Index of methods and functions

`GraphPlot.set_pos()`	Set the position plotting parameters for this GraphPlot.
`GraphPlot.set_vertices()`	Set the vertex plotting parameters for this GraphPlot.
`GraphPlot.set_edges()`	Set the edge (or arrow) plotting parameters for the GraphPlot object.
`GraphPlot.show()`	Show the (Di)Graph associated with this GraphPlot object.
`GraphPlot.plot()`	Return a graphics object representing the (di)graph.
`GraphPlot.layout_tree()`	Compute a nice layout of a tree.

class sage.graphs.graph_plot.GraphPlot(graph, options)[source]¶

Bases: SageObject

Return a GraphPlot object, which stores all the parameters needed for plotting (Di)Graphs.

A GraphPlot has a plot and show function, as well as some functions to set parameters for vertices and edges. This constructor assumes default options are set. Defaults are shown in the example below.

EXAMPLES:

Sage

sage: from sage.graphs.graph_plot import GraphPlot
sage: options = {
....:     'vertex_size': 200,
....:     'vertex_labels': True,
....:     'layout': None,
....:     'edge_style': 'solid',
....:     'edge_color': 'black',
....:     'edge_colors': None,
....:     'edge_labels': False,
....:     'iterations': 50,
....:     'tree_orientation': 'down',
....:     'heights': None,
....:     'graph_border': False,
....:     'talk': False,
....:     'color_by_label': False,
....:     'partition': None,
....:     'dist': .075,
....:     'max_dist': 1.5,
....:     'loop_size': .075,
....:     'edge_labels_background': 'transparent'}
sage: g = Graph({0: [1, 2], 2: [3], 4: [0, 1]})
sage: GP = GraphPlot(g, options)

Python

>>> from sage.all import *
>>> from sage.graphs.graph_plot import GraphPlot
>>> options = {
...     'vertex_size': Integer(200),
...     'vertex_labels': True,
...     'layout': None,
...     'edge_style': 'solid',
...     'edge_color': 'black',
...     'edge_colors': None,
...     'edge_labels': False,
...     'iterations': Integer(50),
...     'tree_orientation': 'down',
...     'heights': None,
...     'graph_border': False,
...     'talk': False,
...     'color_by_label': False,
...     'partition': None,
...     'dist': RealNumber('.075'),
...     'max_dist': RealNumber('1.5'),
...     'loop_size': RealNumber('.075'),
...     'edge_labels_background': 'transparent'}
>>> g = Graph({Integer(0): [Integer(1), Integer(2)], Integer(2): [Integer(3)], Integer(4): [Integer(0), Integer(1)]})
>>> GP = GraphPlot(g, options)

layout_tree(root, orientation)[source]¶

Compute a nice layout of a tree.

INPUT:

root – the root vertex
orientation – whether to place the root at the top or at the bottom:
- orientation="down" – children are placed below their parent
- orientation="top" – children are placed above their parent

EXAMPLES:

Sage

sage: from sage.graphs.graph_plot import GraphPlot
sage: G = graphs.HoffmanSingletonGraph()
sage: T = Graph()
sage: T.add_edges(G.min_spanning_tree(starting_vertex=0))
sage: T.show(layout='tree', tree_root=0)  # indirect doctest

Python

>>> from sage.all import *
>>> from sage.graphs.graph_plot import GraphPlot
>>> G = graphs.HoffmanSingletonGraph()
>>> T = Graph()
>>> T.add_edges(G.min_spanning_tree(starting_vertex=Integer(0)))
>>> T.show(layout='tree', tree_root=Integer(0))  # indirect doctest

plot(**kwds)[source]¶

Return a graphics object representing the (di)graph.

INPUT:

The options accepted by this method are to be found in the documentation of the sage.graphs.graph_plot module, and the show() method.

Note

See the module's documentation for information on default values of this method.

We can specify some pretty precise plotting of familiar graphs:

Sage

sage: from math import sin, cos, pi
sage: P = graphs.PetersenGraph()
sage: d = {'#FF0000': [0, 5], '#FF9900': [1, 6], '#FFFF00': [2, 7],
....:      '#00FF00': [3, 8], '#0000FF': [4,9]}
sage: pos_dict = {}
sage: for i in range(5):
....:  x = float(cos(pi/2 + ((2*pi)/5)*i))
....:  y = float(sin(pi/2 + ((2*pi)/5)*i))
....:  pos_dict[i] = [x,y]
...
sage: for i in range(5, 10):
....:  x = float(0.5*cos(pi/2 + ((2*pi)/5)*i))
....:  y = float(0.5*sin(pi/2 + ((2*pi)/5)*i))
....:  pos_dict[i] = [x,y]
...
sage: pl = P.graphplot(pos=pos_dict, vertex_colors=d)
sage: pl.show()

Python

>>> from sage.all import *
>>> from math import sin, cos, pi
>>> P = graphs.PetersenGraph()
>>> d = {'#FF0000': [Integer(0), Integer(5)], '#FF9900': [Integer(1), Integer(6)], '#FFFF00': [Integer(2), Integer(7)],
...      '#00FF00': [Integer(3), Integer(8)], '#0000FF': [Integer(4),Integer(9)]}
>>> pos_dict = {}
>>> for i in range(Integer(5)):
...  x = float(cos(pi/Integer(2) + ((Integer(2)*pi)/Integer(5))*i))
...  y = float(sin(pi/Integer(2) + ((Integer(2)*pi)/Integer(5))*i))
...  pos_dict[i] = [x,y]
...
>>> for i in range(Integer(5), Integer(10)):
...  x = float(RealNumber('0.5')*cos(pi/Integer(2) + ((Integer(2)*pi)/Integer(5))*i))
...  y = float(RealNumber('0.5')*sin(pi/Integer(2) + ((Integer(2)*pi)/Integer(5))*i))
...  pos_dict[i] = [x,y]
...
>>> pl = P.graphplot(pos=pos_dict, vertex_colors=d)
>>> pl.show()

Here are some more common graphs with typical options:

Sage

sage: C = graphs.CubeGraph(8)
sage: P = C.graphplot(vertex_labels=False, vertex_size=0,
....:                 graph_border=True)
sage: P.show()

Python

>>> from sage.all import *
>>> C = graphs.CubeGraph(Integer(8))
>>> P = C.graphplot(vertex_labels=False, vertex_size=Integer(0),
...                 graph_border=True)
>>> P.show()

Sage

sage: G = graphs.HeawoodGraph().copy(sparse=True)
sage: for u, v, l in G.edges(sort=True):
....:     G.set_edge_label(u, v, f'({u},{v})')
sage: G.graphplot(edge_labels=True).show()

Python

>>> from sage.all import *
>>> G = graphs.HeawoodGraph().copy(sparse=True)
>>> for u, v, l in G.edges(sort=True):
...     G.set_edge_label(u, v, f'({u},{v})')
>>> G.graphplot(edge_labels=True).show()

The options for plotting also work with directed graphs:

Sage

sage: D = DiGraph({
....:     0: [1, 10, 19], 1: [8, 2], 2: [3, 6], 3: [19, 4],
....:     4: [17, 5], 5: [6, 15], 6: [7], 7: [8, 14], 8: [9],
....:     9: [10, 13], 10: [11], 11: [12, 18], 12: [16, 13],
....:     13: [14], 14: [15], 15: [16], 16: [17], 17: [18],
....:     18: [19], 19: []})
sage: for u, v, l in D.edges(sort=True):
....:     D.set_edge_label(u, v, f'({u},{v})')
sage: D.graphplot(edge_labels=True, layout='circular').show()

Python

>>> from sage.all import *
>>> D = DiGraph({
...     Integer(0): [Integer(1), Integer(10), Integer(19)], Integer(1): [Integer(8), Integer(2)], Integer(2): [Integer(3), Integer(6)], Integer(3): [Integer(19), Integer(4)],
...     Integer(4): [Integer(17), Integer(5)], Integer(5): [Integer(6), Integer(15)], Integer(6): [Integer(7)], Integer(7): [Integer(8), Integer(14)], Integer(8): [Integer(9)],
...     Integer(9): [Integer(10), Integer(13)], Integer(10): [Integer(11)], Integer(11): [Integer(12), Integer(18)], Integer(12): [Integer(16), Integer(13)],
...     Integer(13): [Integer(14)], Integer(14): [Integer(15)], Integer(15): [Integer(16)], Integer(16): [Integer(17)], Integer(17): [Integer(18)],
...     Integer(18): [Integer(19)], Integer(19): []})
>>> for u, v, l in D.edges(sort=True):
...     D.set_edge_label(u, v, f'({u},{v})')
>>> D.graphplot(edge_labels=True, layout='circular').show()

This example shows off the coloring of edges:

Sage

sage: from sage.plot.colors import rainbow
sage: C = graphs.CubeGraph(5)
sage: R = rainbow(5)
sage: edge_colors = {}
sage: for i in range(5):
....:     edge_colors[R[i]] = []
sage: for u, v, l in C.edges(sort=True):
....:     for i in range(5):
....:         if u[i] != v[i]:
....:             edge_colors[R[i]].append((u, v, l))
sage: C.graphplot(vertex_labels=False, vertex_size=0,
....:             edge_colors=edge_colors).show()

Python

>>> from sage.all import *
>>> from sage.plot.colors import rainbow
>>> C = graphs.CubeGraph(Integer(5))
>>> R = rainbow(Integer(5))
>>> edge_colors = {}
>>> for i in range(Integer(5)):
...     edge_colors[R[i]] = []
>>> for u, v, l in C.edges(sort=True):
...     for i in range(Integer(5)):
...         if u[i] != v[i]:
...             edge_colors[R[i]].append((u, v, l))
>>> C.graphplot(vertex_labels=False, vertex_size=Integer(0),
...             edge_colors=edge_colors).show()

With the partition option, we can separate out same-color groups of vertices:

Sage

sage: D = graphs.DodecahedralGraph()
sage: Pi = [[6, 5, 15, 14, 7], [16, 13, 8, 2, 4],
....:       [12, 17, 9, 3, 1], [0, 19, 18, 10, 11]]
sage: D.show(partition=Pi)

Python

>>> from sage.all import *
>>> D = graphs.DodecahedralGraph()
>>> Pi = [[Integer(6), Integer(5), Integer(15), Integer(14), Integer(7)], [Integer(16), Integer(13), Integer(8), Integer(2), Integer(4)],
...       [Integer(12), Integer(17), Integer(9), Integer(3), Integer(1)], [Integer(0), Integer(19), Integer(18), Integer(10), Integer(11)]]
>>> D.show(partition=Pi)

Loops are also plotted correctly:

Sage

sage: G = graphs.PetersenGraph()
sage: G.allow_loops(True)
sage: G.add_edge(0,0)
sage: G.show()

Python

>>> from sage.all import *
>>> G = graphs.PetersenGraph()
>>> G.allow_loops(True)
>>> G.add_edge(Integer(0),Integer(0))
>>> G.show()

Sage

sage: D = DiGraph({0:[0,1], 1:[2], 2:[3]}, loops=True)
sage: D.show()
sage: D.show(edge_colors={(0, 1, 0): [(0, 1, None), (1, 2, None)],
....:                     (0, 0, 0): [(2, 3, None)]})

Python

>>> from sage.all import *
>>> D = DiGraph({Integer(0):[Integer(0),Integer(1)], Integer(1):[Integer(2)], Integer(2):[Integer(3)]}, loops=True)
>>> D.show()
>>> D.show(edge_colors={(Integer(0), Integer(1), Integer(0)): [(Integer(0), Integer(1), None), (Integer(1), Integer(2), None)],
...                     (Integer(0), Integer(0), Integer(0)): [(Integer(2), Integer(3), None)]})

More options:

Sage

sage: pos = {0: [0.0, 1.5], 1: [-0.8, 0.3], 2: [-0.6, -0.8],
....:        3:[0.6, -0.8], 4:[0.8, 0.3]}
sage: g = Graph({0: [1], 1: [2], 2: [3], 3: [4], 4: [0]})
sage: g.graphplot(pos=pos, layout='spring', iterations=0).plot()
Graphics object consisting of 11 graphics primitives

Python

>>> from sage.all import *
>>> pos = {Integer(0): [RealNumber('0.0'), RealNumber('1.5')], Integer(1): [-RealNumber('0.8'), RealNumber('0.3')], Integer(2): [-RealNumber('0.6'), -RealNumber('0.8')],
...        Integer(3):[RealNumber('0.6'), -RealNumber('0.8')], Integer(4):[RealNumber('0.8'), RealNumber('0.3')]}
>>> g = Graph({Integer(0): [Integer(1)], Integer(1): [Integer(2)], Integer(2): [Integer(3)], Integer(3): [Integer(4)], Integer(4): [Integer(0)]})
>>> g.graphplot(pos=pos, layout='spring', iterations=Integer(0)).plot()
Graphics object consisting of 11 graphics primitives

Sage

sage: G = Graph()
sage: P = G.graphplot().plot()
sage: P.axes()
False
sage: G = DiGraph()
sage: P = G.graphplot().plot()
sage: P.axes()
False

Python

>>> from sage.all import *
>>> G = Graph()
>>> P = G.graphplot().plot()
>>> P.axes()
False
>>> G = DiGraph()
>>> P = G.graphplot().plot()
>>> P.axes()
False

We can plot multiple graphs:

Sage

sage: T = list(graphs.trees(7))
sage: t = T[3]
sage: t.graphplot(heights={0: [0], 1: [4, 5, 1],
....:                      2: [2], 3: [3, 6]}
....:            ).plot()
Graphics object consisting of 14 graphics primitives

Python

>>> from sage.all import *
>>> T = list(graphs.trees(Integer(7)))
>>> t = T[Integer(3)]
>>> t.graphplot(heights={Integer(0): [Integer(0)], Integer(1): [Integer(4), Integer(5), Integer(1)],
...                      Integer(2): [Integer(2)], Integer(3): [Integer(3), Integer(6)]}
...            ).plot()
Graphics object consisting of 14 graphics primitives

Sage

sage: T = list(graphs.trees(7))
sage: t = T[3]
sage: t.graphplot(heights={0: [0], 1: [4, 5, 1],
....:                      2: [2], 3: [3, 6]}
....:            ).plot()
Graphics object consisting of 14 graphics primitives

Python

>>> from sage.all import *
>>> T = list(graphs.trees(Integer(7)))
>>> t = T[Integer(3)]
>>> t.graphplot(heights={Integer(0): [Integer(0)], Integer(1): [Integer(4), Integer(5), Integer(1)],
...                      Integer(2): [Integer(2)], Integer(3): [Integer(3), Integer(6)]}
...            ).plot()
Graphics object consisting of 14 graphics primitives

Sage

sage: t.set_edge_label(0, 1, -7)
sage: t.set_edge_label(0, 5, 3)
sage: t.set_edge_label(0, 5, 99)
sage: t.set_edge_label(1, 2, 1000)
sage: t.set_edge_label(3, 2, 'spam')
sage: t.set_edge_label(2, 6, 3/2)
sage: t.set_edge_label(0, 4, 66)
sage: t.graphplot(heights={0: [0], 1: [4, 5, 1],
....:                      2: [2], 3: [3, 6]},
....:             edge_labels=True
....:            ).plot()
Graphics object consisting of 20 graphics primitives

Python

>>> from sage.all import *
>>> t.set_edge_label(Integer(0), Integer(1), -Integer(7))
>>> t.set_edge_label(Integer(0), Integer(5), Integer(3))
>>> t.set_edge_label(Integer(0), Integer(5), Integer(99))
>>> t.set_edge_label(Integer(1), Integer(2), Integer(1000))
>>> t.set_edge_label(Integer(3), Integer(2), 'spam')
>>> t.set_edge_label(Integer(2), Integer(6), Integer(3)/Integer(2))
>>> t.set_edge_label(Integer(0), Integer(4), Integer(66))
>>> t.graphplot(heights={Integer(0): [Integer(0)], Integer(1): [Integer(4), Integer(5), Integer(1)],
...                      Integer(2): [Integer(2)], Integer(3): [Integer(3), Integer(6)]},
...             edge_labels=True
...            ).plot()
Graphics object consisting of 20 graphics primitives

Sage

sage: T = list(graphs.trees(7))
sage: t = T[3]
sage: t.graphplot(layout='tree').show()

Python

>>> from sage.all import *
>>> T = list(graphs.trees(Integer(7)))
>>> t = T[Integer(3)]
>>> t.graphplot(layout='tree').show()

The tree layout is also useful:

Sage

sage: t = DiGraph('JCC???@A??GO??CO??GO??')
sage: t.graphplot(layout='tree', tree_root=0,
....:             tree_orientation="up"
....:            ).show()

Python

>>> from sage.all import *
>>> t = DiGraph('JCC???@A??GO??CO??GO??')
>>> t.graphplot(layout='tree', tree_root=Integer(0),
...             tree_orientation="up"
...            ).show()

More examples:

Sage

sage: D = DiGraph({0:[1,2,3], 2:[1,4], 3:[0]})
sage: D.graphplot().show()

Python

>>> from sage.all import *
>>> D = DiGraph({Integer(0):[Integer(1),Integer(2),Integer(3)], Integer(2):[Integer(1),Integer(4)], Integer(3):[Integer(0)]})
>>> D.graphplot().show()

Sage

sage: D = DiGraph(multiedges=True, sparse=True)
sage: for i in range(5):
....:   D.add_edge((i, i + 1, 'a'))
....:   D.add_edge((i, i - 1, 'b'))
sage: D.graphplot(edge_labels=True,
....:             edge_colors=D._color_by_label()
....:            ).plot()
Graphics object consisting of 34 graphics primitives

Python

>>> from sage.all import *
>>> D = DiGraph(multiedges=True, sparse=True)
>>> for i in range(Integer(5)):
...   D.add_edge((i, i + Integer(1), 'a'))
...   D.add_edge((i, i - Integer(1), 'b'))
>>> D.graphplot(edge_labels=True,
...             edge_colors=D._color_by_label()
...            ).plot()
Graphics object consisting of 34 graphics primitives

Sage

sage: g = Graph({}, loops=True, multiedges=True, sparse=True)
sage: g.add_edges([(0, 0, 'a'), (0, 0, 'b'), (0, 1, 'c'),
....:              (0, 1, 'd'), (0, 1, 'e'), (0, 1, 'f'),
....:              (0, 1, 'f'), (2, 1, 'g'), (2, 2, 'h')])
sage: g.graphplot(edge_labels=True,
....:             color_by_label=True,
....:             edge_style='dashed'
....:            ).plot()
Graphics object consisting of 22 graphics primitives

Python

>>> from sage.all import *
>>> g = Graph({}, loops=True, multiedges=True, sparse=True)
>>> g.add_edges([(Integer(0), Integer(0), 'a'), (Integer(0), Integer(0), 'b'), (Integer(0), Integer(1), 'c'),
...              (Integer(0), Integer(1), 'd'), (Integer(0), Integer(1), 'e'), (Integer(0), Integer(1), 'f'),
...              (Integer(0), Integer(1), 'f'), (Integer(2), Integer(1), 'g'), (Integer(2), Integer(2), 'h')])
>>> g.graphplot(edge_labels=True,
...             color_by_label=True,
...             edge_style='dashed'
...            ).plot()
Graphics object consisting of 22 graphics primitives

The edge_style option may be provided in the short format too:

Sage

sage: g.graphplot(edge_labels=True,
....:             color_by_label=True,
....:             edge_style='--'
....:            ).plot()
Graphics object consisting of 22 graphics primitives

Python

>>> from sage.all import *
>>> g.graphplot(edge_labels=True,
...             color_by_label=True,
...             edge_style='--'
...            ).plot()
Graphics object consisting of 22 graphics primitives

set_edges(**edge_options)[source]¶

Set edge plotting parameters for the GraphPlot object.

This function is called by the constructor but can also be called to update the edge options of an existing GraphPlot object. Note that the changes are cumulative.

EXAMPLES:

Sage

sage: g = Graph(loops=True, multiedges=True, sparse=True)
sage: g.add_edges([(0, 0, 'a'), (0, 0, 'b'), (0, 1, 'c'),
....:              (0, 1, 'd'), (0, 1, 'e'), (0, 1, 'f'),
....:              (0, 1, 'f'), (2, 1, 'g'), (2, 2, 'h')])
sage: GP = g.graphplot(vertex_size=100, edge_labels=True,
....:                  color_by_label=True, edge_style='dashed')
sage: GP.set_edges(edge_style='solid')
sage: GP.plot()
Graphics object consisting of 22 graphics primitives

Python

>>> from sage.all import *
>>> g = Graph(loops=True, multiedges=True, sparse=True)
>>> g.add_edges([(Integer(0), Integer(0), 'a'), (Integer(0), Integer(0), 'b'), (Integer(0), Integer(1), 'c'),
...              (Integer(0), Integer(1), 'd'), (Integer(0), Integer(1), 'e'), (Integer(0), Integer(1), 'f'),
...              (Integer(0), Integer(1), 'f'), (Integer(2), Integer(1), 'g'), (Integer(2), Integer(2), 'h')])
>>> GP = g.graphplot(vertex_size=Integer(100), edge_labels=True,
...                  color_by_label=True, edge_style='dashed')
>>> GP.set_edges(edge_style='solid')
>>> GP.plot()
Graphics object consisting of 22 graphics primitives

Sage

sage: GP.set_edges(edge_color='black')
sage: GP.plot()
Graphics object consisting of 22 graphics primitives

Python

>>> from sage.all import *
>>> GP.set_edges(edge_color='black')
>>> GP.plot()
Graphics object consisting of 22 graphics primitives

Sage

sage: d = DiGraph(loops=True, multiedges=True, sparse=True)
sage: d.add_edges([(0, 0, 'a'), (0, 0, 'b'), (0, 1, 'c'),
....:              (0, 1, 'd'), (0, 1, 'e'), (0, 1, 'f'),
....:              (0, 1, 'f'), (2, 1, 'g'), (2, 2, 'h')])
sage: GP = d.graphplot(vertex_size=100, edge_labels=True,
....:                  color_by_label=True, edge_style='dashed')
sage: GP.set_edges(edge_style='solid')
sage: GP.plot()
Graphics object consisting of 24 graphics primitives

Python

>>> from sage.all import *
>>> d = DiGraph(loops=True, multiedges=True, sparse=True)
>>> d.add_edges([(Integer(0), Integer(0), 'a'), (Integer(0), Integer(0), 'b'), (Integer(0), Integer(1), 'c'),
...              (Integer(0), Integer(1), 'd'), (Integer(0), Integer(1), 'e'), (Integer(0), Integer(1), 'f'),
...              (Integer(0), Integer(1), 'f'), (Integer(2), Integer(1), 'g'), (Integer(2), Integer(2), 'h')])
>>> GP = d.graphplot(vertex_size=Integer(100), edge_labels=True,
...                  color_by_label=True, edge_style='dashed')
>>> GP.set_edges(edge_style='solid')
>>> GP.plot()
Graphics object consisting of 24 graphics primitives

Sage

sage: GP.set_edges(edge_color='black')
sage: GP.plot()
Graphics object consisting of 24 graphics primitives

Python

>>> from sage.all import *
>>> GP.set_edges(edge_color='black')
>>> GP.plot()
Graphics object consisting of 24 graphics primitives

set_pos()[source]¶

Set the position plotting parameters for this GraphPlot.

EXAMPLES:

This function is called implicitly by the code below:

Sage

sage: g = Graph({0: [1, 2], 2: [3], 4: [0, 1]})
sage: g.graphplot(save_pos=True, layout='circular')  # indirect doctest
GraphPlot object for Graph on 5 vertices

Python

>>> from sage.all import *
>>> g = Graph({Integer(0): [Integer(1), Integer(2)], Integer(2): [Integer(3)], Integer(4): [Integer(0), Integer(1)]})
>>> g.graphplot(save_pos=True, layout='circular')  # indirect doctest
GraphPlot object for Graph on 5 vertices

The following illustrates the format of a position dictionary, but due to numerical noise we do not check the values themselves:

Sage

sage: g.get_pos()
{0: (0.0, 1.0),
 1: (-0.951..., 0.309...),
 2: (-0.587..., -0.809...),
 3: (0.587..., -0.809...),
 4: (0.951..., 0.309...)}

Python

>>> from sage.all import *
>>> g.get_pos()
{0: (0.0, 1.0),
 1: (-0.951..., 0.309...),
 2: (-0.587..., -0.809...),
 3: (0.587..., -0.809...),
 4: (0.951..., 0.309...)}

Sage

sage: T = list(graphs.trees(7))
sage: t = T[3]
sage: t.plot(heights={0: [0], 1: [4, 5, 1], 2: [2], 3: [3, 6]})
Graphics object consisting of 14 graphics primitives

Python

>>> from sage.all import *
>>> T = list(graphs.trees(Integer(7)))
>>> t = T[Integer(3)]
>>> t.plot(heights={Integer(0): [Integer(0)], Integer(1): [Integer(4), Integer(5), Integer(1)], Integer(2): [Integer(2)], Integer(3): [Integer(3), Integer(6)]})
Graphics object consisting of 14 graphics primitives

set_vertices(**vertex_options)[source]¶

Set the vertex plotting parameters for this GraphPlot.

This function is called by the constructor but can also be called to make updates to the vertex options of an existing GraphPlot object. Note that the changes are cumulative.

EXAMPLES:

Sage

sage: g = Graph({}, loops=True, multiedges=True, sparse=True)
sage: g.add_edges([(0, 0, 'a'), (0, 0, 'b'), (0, 1, 'c'),
....:              (0, 1, 'd'), (0, 1, 'e'), (0, 1, 'f'),
....:              (0, 1, 'f'), (2, 1, 'g'), (2, 2, 'h')])
sage: GP = g.graphplot(vertex_size=100, edge_labels=True,
....:                  color_by_label=True, edge_style='dashed')
sage: GP.set_vertices(talk=True)
sage: GP.plot()
Graphics object consisting of 22 graphics primitives
sage: GP.set_vertices(vertex_color='green', vertex_shape='^')
sage: GP.plot()
Graphics object consisting of 22 graphics primitives

Python

>>> from sage.all import *
>>> g = Graph({}, loops=True, multiedges=True, sparse=True)
>>> g.add_edges([(Integer(0), Integer(0), 'a'), (Integer(0), Integer(0), 'b'), (Integer(0), Integer(1), 'c'),
...              (Integer(0), Integer(1), 'd'), (Integer(0), Integer(1), 'e'), (Integer(0), Integer(1), 'f'),
...              (Integer(0), Integer(1), 'f'), (Integer(2), Integer(1), 'g'), (Integer(2), Integer(2), 'h')])
>>> GP = g.graphplot(vertex_size=Integer(100), edge_labels=True,
...                  color_by_label=True, edge_style='dashed')
>>> GP.set_vertices(talk=True)
>>> GP.plot()
Graphics object consisting of 22 graphics primitives
>>> GP.set_vertices(vertex_color='green', vertex_shape='^')
>>> GP.plot()
Graphics object consisting of 22 graphics primitives

Vertex labels are flexible:

Sage

sage: g = graphs.PathGraph(4)
sage: g.plot(vertex_labels=False)
Graphics object consisting of 4 graphics primitives

Python

>>> from sage.all import *
>>> g = graphs.PathGraph(Integer(4))
>>> g.plot(vertex_labels=False)
Graphics object consisting of 4 graphics primitives

Sage

sage: g = graphs.PathGraph(4)
sage: g.plot(vertex_labels=True)
Graphics object consisting of 8 graphics primitives

Python

>>> from sage.all import *
>>> g = graphs.PathGraph(Integer(4))
>>> g.plot(vertex_labels=True)
Graphics object consisting of 8 graphics primitives

Sage

sage: g = graphs.PathGraph(4)
sage: g.plot(vertex_labels=dict(zip(g, ['+', '-', '/', '*'])))
Graphics object consisting of 8 graphics primitives

Python

>>> from sage.all import *
>>> g = graphs.PathGraph(Integer(4))
>>> g.plot(vertex_labels=dict(zip(g, ['+', '-', '/', '*'])))
Graphics object consisting of 8 graphics primitives

Sage

sage: g = graphs.PathGraph(4)
sage: g.plot(vertex_labels=lambda x: str(x % 2))
Graphics object consisting of 8 graphics primitives

Python

>>> from sage.all import *
>>> g = graphs.PathGraph(Integer(4))
>>> g.plot(vertex_labels=lambda x: str(x % Integer(2)))
Graphics object consisting of 8 graphics primitives

show(**kwds)[source]¶

Show the (di)graph associated with this GraphPlot object.

INPUT:

This method accepts all parameters of sage.plot.graphics.Graphics.show().

Note

See the module's documentation for information on default values of this method.
Any options not used by plot will be passed on to the show() method.

EXAMPLES:

Sage

sage: C = graphs.CubeGraph(8)
sage: P = C.graphplot(vertex_labels=False, vertex_size=0,
....:                 graph_border=True)
sage: P.show()

Python

>>> from sage.all import *
>>> C = graphs.CubeGraph(Integer(8))
>>> P = C.graphplot(vertex_labels=False, vertex_size=Integer(0),
...                 graph_border=True)
>>> P.show()