rez.vendor.pygraph.classes.digraph

Digraph class

class rez.vendor.pygraph.classes.digraph.digraph

Bases: basegraph, common, labeling

Digraph class.

Digraphs are built of nodes and directed edges.

@sort: __eq__, __init__, __ne__, add_edge, add_node, del_edge, del_node, edges, has_edge, has_node, incidents, neighbors, node_order, nodes

DIRECTED = True

__init__()

Initialize a digraph.

nodes()

Return node list.

@rtype: list @return: Node list.

neighbors(node)

Return all nodes that are directly accessible from given node.

@type node: node @param node: Node identifier

@rtype: list @return: List of nodes directly accessible from given node.

incidents(node)

Return all nodes that are incident to the given node.

@type node: node @param node: Node identifier

@rtype: list @return: List of nodes directly accessible from given node.

edges()

Return all edges in the graph.

@rtype: list @return: List of all edges in the graph.

has_node(node)

Return whether the requested node exists.

@type node: node @param node: Node identifier

@rtype: boolean @return: Truth-value for node existence.

add_node(node, attrs=None)

Add given node to the graph.

@attention: While nodes can be of any type, it’s strongly recommended to use only numbers and single-line strings as node identifiers if you intend to use write().

@type node: node @param node: Node identifier.

@type attrs: list @param attrs: List of node attributes specified as (attribute, value) tuples.

add_edge(edge, wt=1, label='', attrs=[])

Add an directed edge to the graph connecting two nodes.

An edge, here, is a pair of nodes like C{(n, m)}.

@type edge: tuple @param edge: Edge.

@type wt: number @param wt: Edge weight.

@type label: string @param label: Edge label.

@type attrs: list @param attrs: List of node attributes specified as (attribute, value) tuples.

del_node(node)

Remove a node from the graph.

@type node: node @param node: Node identifier.

del_edge(edge)

Remove an directed edge from the graph.

@type edge: tuple @param edge: Edge.

has_edge(edge)

Return whether an edge exists.

@type edge: tuple @param edge: Edge.

@rtype: boolean @return: Truth-value for edge existence.

node_order(node)

Return the order of the given node.

@rtype: number @return: Order of the given node.

DEFAULT_LABEL = ''

DEFAULT_WEIGHT = 1

LABEL_ATTRIBUTE_NAME = 'label'

WEIGHT_ATTRIBUTE_NAME = 'weight'

add_edge_attribute(edge, attr)

Add attribute to the given edge.

@type edge: edge @param edge: One edge.

@type attr: tuple @param attr: Node attribute specified as a tuple in the form (attribute, value).

add_edge_attributes(edge, attrs)

Append a sequence of attributes to the given edge

@type edge: edge @param edge: One edge.

@type attrs: tuple @param attrs: Node attributes specified as a sequence of tuples in the form (attribute, value).

add_graph(other)

Add other graph to this graph.

@attention: Attributes and labels are not preserved.

@type other: graph @param other: Graph

add_node_attribute(node, attr)

Add attribute to the given node.

@type node: node @param node: Node identifier

@type attr: tuple @param attr: Node attribute specified as a tuple in the form (attribute, value).

add_nodes(nodelist)

Add given nodes to the graph.

@attention: While nodes can be of any type, it’s strongly recommended to use only numbers and single-line strings as node identifiers if you intend to use write(). Objects used to identify nodes absolutely must be hashable. If you need attach a mutable or non-hashable node, consider using the labeling feature.

@type nodelist: list @param nodelist: List of nodes to be added to the graph.

add_spanning_tree(st)

Add a spanning tree to the graph.

@type st: dictionary @param st: Spanning tree.

complete()

Make the graph a complete graph.

@attention: This will modify the current graph.

del_edge_labeling(edge)

del_node_labeling(node)

edge_attributes(edge)

Return the attributes of the given edge.

@type edge: edge @param edge: One edge.

@rtype: list @return: List of attributes specified tuples in the form (attribute, value).

edge_label(edge)

Get the label of an edge.

@type edge: edge @param edge: One edge.

@rtype: string @return: Edge label

edge_weight(edge)

Get the weight of an edge.

@type edge: edge @param edge: One edge.

@rtype: number @return: Edge weight.

get_edge_properties(edge)

inverse()

Return the inverse of the graph.

@rtype: graph @return: Complement graph for the graph.

node_attributes(node)

Return the attributes of the given node.

@type node: node @param node: Node identifier

@rtype: list @return: List of attributes specified tuples in the form (attribute, value).

order()

Return the order of self, this is defined as the number of nodes in the graph.

@rtype: number @return: Size of the graph.

reverse()

Generate the reverse of a directed graph, returns an identical graph if not directed. Attributes & weights are preserved.

@rtype: digraph @return: The directed graph that should be reversed.

set_edge_label(edge, label)

Set the label of an edge.

@type edge: edge @param edge: One edge.

@type label: string @param label: Edge label.

set_edge_properties(edge, **properties)

set_edge_weight(edge, wt)

Set the weight of an edge.

@type edge: edge @param edge: One edge.

@type wt: number @param wt: Edge weight.