Class for Graphviz agraph type.
Example use
>>> G=AGraph()
>>> G=AGraph(directed=True)
>>> G=AGraph("file.dot")
Graphviz graph keyword parameters are processed so you may add them like
>>> G=AGraph(landscape='true',ranksep='0.1')
or alternatively
>>> G=AGraph()
>>> G.graph_attr.update(landscape='true',ranksep='0.1')
and
>>> G.node_attr.update(color='red')
>>> G.edge_attr.update(len='2.0',color='blue')
See http://www.graphviz.org/doc/info/attrs.html for a list of attributes.
Keyword parameters:
thing is a generic input type (filename, string, handle to pointer, dictionary of dictionaries). An attempt is made to automaticaly detect the type so you may write for example:
>>> d={'1': {'2': None}, '2': {'1': None, '3': None}, '3': {'2': None}}
>>> A=AGraph(d)
>>> s=AGraph.to_string()
>>> B=AGraph(s)
>>> h=AGraph.handle
>>> C=AGraph(h)
Parameters:
name: String name for the graph
strict: True|False (True for simple graphs)
directed: True|False
data: Dictionary of dictionaries or dictionary of lists
representing nodes or edges to load into intial graph
string: String containing a dot format graph
handle: Swig pointer to an agraph_t data structure
Reverse sufficient edges in digraph to make graph acyclic. Modifies existing graph.
To create a new graph use
>>> A=AGraph()
>>> B=A.acyclic(copy=True)
See the graphviz “acyclic” program for details of the algorithm.
Add a single edge between nodes u and v to the graph.
If u and v are not nodes in they graph they will added.
If u and v is not a strings, conversion to a string will be attempted. String conversion will work if u and v have valid string representation (try e.g. str(u) if you are unsure).
>>> G=AGraph()
>>> G.add_edge('a','b')
>>> G.edges()
[('a', 'b')]
The optional key argument allows assignment of a key to the edge. This is especially useful to distinguish between parallel edges in multi-edge graphs (strict=False).
>>> G=AGraph(strict=False)
>>> G.add_edge('a','b','first')
>>> G.add_edge('a','b','second')
>>> sorted(G.edges())
[('a', 'b', 'first'), ('a', 'b', 'second')]
Attributes can be added when edges are created
>>> G.add_edge('a','b',color='green')
See http://www.graphviz.org/doc/info/attrs.html for a list of attributes.
Add nodes to graph from a container ebunch.
ebunch is a container of edges such as a list or dictionary.
>>> G=AGraph()
>>> elist=[('a','b'),('b','c')]
>>> G.add_edges_from(elist)
Attributes can be added when edges are created
>>> G.add_edges_from(elist, color='green')
Add a single node n.
If n is not a string, conversion to a string will be attempted. String conversion will work if n has valid string representation (try str(n) if you are unsure).
>>> G=AGraph()
>>> G.add_node('a')
>>> G.nodes()
['a']
>>> G.add_node(1) # will be converted to a string
>>> G.nodes()
['a', '1']
Attributes can be added to nodes on creation
>>> G.add_node(2,color='red')
See http://www.graphviz.org/doc/info/attrs.html for a list of attributes.
Anonymous Graphviz nodes are currently not implemented.
Add nodes from a container nbunch.
nbunch can be any iterable container such as a list or dictionary
>>> G=AGraph()
>>> nlist=['a','b',1,'spam']
>>> G.add_nodes_from(nlist)
>>> sorted(G.nodes())
['1', 'a', 'b', 'spam']
Attributes can be added to nodes on creation
>>> G.add_nodes_from(nlist, color='red') # set all nodes in nlist red
Return the degree of nodes given in nbunch container.
Using optional with_labels=True returns a dictionary keyed by node with value set to the degree.
Return an iterator over the degree of the nodes given in nbunch container.
Returns paris of (node,degree).
Remove edge between nodes u and v from the graph.
With optional key argument will only remove an edge matching (u,v,key).
Remove the single node n.
Attempting to remove a node that isn’t in the graph will produce an error.
>>> G=AGraph()
>>> G.add_node('a')
>>> G.remove_node('a')
Remove nodes from a container nbunch.
nbunch can be any iterable container such as a list or dictionary
>>> G=AGraph()
>>> nlist=['a','b',1,'spam']
>>> G.add_nodes_from(nlist)
>>> G.remove_nodes_from(nlist)
Output graph to path in specified format.
An attempt will be made to guess the output format based on the file extension of path. If that fails the format keyword will be used.
Formats (not all may be available on every system depending on how Graphviz was built)
‘canon’, ‘cmap’, ‘cmapx’, ‘cmapx_np’, ‘dia’, ‘dot’, ‘fig’, ‘gd’, ‘gd2’, ‘gif’, ‘hpgl’, ‘imap’, ‘imap_np’, ‘ismap’, ‘jpe’, ‘jpeg’, ‘jpg’, ‘mif’, ‘mp’, ‘pcl’, ‘pdf’, ‘pic’, ‘plain’, ‘plain-ext’, ‘png’, ‘ps’, ‘ps2’, ‘svg’, ‘svgz’, ‘vml’, ‘vmlz’, ‘vrml’, ‘vtx’, ‘wbmp’, ‘xdot’, ‘xlib’
If prog is not specified and the graph has positions (see layout()) then no additional graph positioning will be performed.
Optional prog=[‘neato’|’dot’|’twopi’|’circo’|’fdp’|’nop’] will use specified graphviz layout method.
>>> G=AGraph()
>>> G.layout()
# use current node positions, output ps in ‘file.ps’ >>> G.draw(‘file.ps’)
# use dot to position, output png in ‘file’ >>> G.draw(‘file’, format=’png’,prog=’dot’)
# use keyword ‘args’ to pass additional arguments to graphviz >>> G.draw(‘test.ps’,prog=’twopi’,args=’-Gepsilon=1’)
The layout might take a long time on large graphs.
Return list of edges in the graph.
If the optional nbunch (container of nodes) only edges adjacent to nodes in nbunch will be returned.
>>> G=AGraph()
>>> G.add_edge('a','b')
>>> G.add_edge('c','d')
>>> print sorted(G.edges())
[('a', 'b'), ('c', 'd')]
>>> print G.edges('a')
[('a', 'b')]
Return iterator over out edges in the graph.
If the optional nbunch (container of nodes) only out edges adjacent to nodes in nbunch will be returned.
Load a graph from a string in dot format.
Overwrites any existing graph.
To make a new graph from a string use
>>> s='digraph {1 -> 2}'
>>> A=AGraph()
>>> A.from_string(s)
>>> A=AGraph(string=s) # specify s is a string
>>> A=AGraph(s) # s assumed to be a string during initialization
Return an edge object (Edge) corresponding to edge (u,v).
>>> G=AGraph()
>>> G.add_edge('a','b')
>>> edge=G.get_edge('a','b')
>>> print edge
('a', 'b')
With optional key argument will only get edge matching (u,v,key).
Return a node object (Node) corresponding to node n.
>>> G=AGraph()
>>> G.add_node('a')
>>> node=G.get_node('a')
>>> print node
a
Return True an edge u-v is in the graph or False if not.
>>> G=AGraph()
>>> G.add_edge('a','b')
>>> G.has_edge('a','b')
True
Optional key argument will restrict match to edges (u,v,key).
Return True if u has an edge to v or False if not.
>>> G=AGraph()
>>> G.add_edge('a','b')
>>> G.has_neighbor('a','b')
True
Optional key argument will only find edges (u,v,key).
Return True if n is in the graph or False if not.
>>> G=AGraph()
>>> G.add_node('a')
>>> G.has_node('a')
True
>>> 'a' in G # same as G.has_node('a')
True
Return the in-degree of nodes given in nbunch container.
Using optional with_labels=True returns a dictionary keyed by node with value set to the degree.
Return an iterator over the in-degree of the nodes given in nbunch container.
Returns paris of (node,degree).
Return iterator over out edges in the graph.
If the optional nbunch (container of nodes) only out edges adjacent to nodes in nbunch will be returned.
Return True if graph is strict or False if not.
Strict graphs do not allow parallel edges or self loops.
Return an iterator over the degree of the nodes given in nbunch container.
Returns paris of (node,degree).
Return iterator over out edges in the graph.
If the optional nbunch (container of nodes) only out edges adjacent to nodes in nbunch will be returned.
Return an iterator over the in-degree of the nodes given in nbunch container.
Returns paris of (node,degree).
Return iterator over out edges in the graph.
If the optional nbunch (container of nodes) only out edges adjacent to nodes in nbunch will be returned.
Return an iterator over the out-degree of the nodes given in nbunch container.
Returns paris of (node,degree).
Return iterator over out edges in the graph.
If the optional nbunch (container of nodes) only out edges adjacent to nodes in nbunch will be returned.
Assign positions to nodes in graph.
Optional prog=[‘neato’|’dot’|’twopi’|’circo’|’fdp’|’nop’] will use specified graphviz layout method.
>>> A=AGraph()
>>> A.layout() # uses neato
>>> A.layout(prog='dot')
Use keyword args to add additional arguments to graphviz programs.
The layout might take a long time on large graphs.
Return the out-degree of nodes given in nbunch container.
Using optional with_labels=True returns a dictionary keyed by node with value set to the degree.
Return an iterator over the out-degree of the nodes given in nbunch container.
Returns paris of (node,degree).
Return list of out edges in the graph.
If the optional nbunch (container of nodes) only out edges adjacent to nodes in nbunch will be returned.
Return iterator over out edges in the graph.
If the optional nbunch (container of nodes) only out edges adjacent to nodes in nbunch will be returned.
Read graph from dot format file on path.
path can be a file name or file handle
use:
G.read('file.dot')
Remove edge between nodes u and v from the graph.
With optional key argument will only remove an edge matching (u,v,key).
Remove the single node n.
Attempting to remove a node that isn’t in the graph will produce an error.
>>> G=AGraph()
>>> G.add_node('a')
>>> G.remove_node('a')
Remove nodes from a container nbunch.
nbunch can be any iterable container such as a list or dictionary
>>> G=AGraph()
>>> nlist=['a','b',1,'spam']
>>> G.add_nodes_from(nlist)
>>> G.remove_nodes_from(nlist)
Return True if graph is strict or False if not.
Strict graphs do not allow parallel edges or self loops.
Return directed copy of graph.
Each undirected edge u-v is represented as two directed edges u->v and v->u.
Transitive reduction of graph. Modifies existing graph.
To create a new graph use
>>> A=AGraph()
>>> B=A.tred(copy=True)
See the graphviz “tred” program for details of the algorithm.
Write graph in dot format to file on path.
path can be a file name or file handle
use:
G.write('file.dot')