edge Module¶
-
class
graphistry.layout.graph.edge.
Edge
(x, y, w=1, data=None, connect=False) Bases:
graphistry.layout.graph.edgeBase.EdgeBase
A graph edge.
- Attributes
data (object): an optional payload
w (int): an optional weight associated with the edge (default 1) used by Dijkstra to find min-flow paths.
feedback (bool): whether the Tarjan algorithm has inverted this edge to de-cycle the graph.
-
attach
() Attach this edge to the edge collections of the vertices.
-
data
: object
-
detach
() Removes this edge from the edge collections of the vertices.
-
feedback
: bool
-
w
: int
edgeBase Module¶
-
class
graphistry.layout.graph.edgeBase.
EdgeBase
(x, y) Bases:
object
Base class for edges.
- Attributes
degree (int): degree of the edge (number of unique vertices).
v (list[Vertex]): list of vertices associated with this edge.
-
degree
: int Is 0 if a loop, otherwise 1.
graph Module¶
-
class
graphistry.layout.graph.graph.
Graph
(vertices=None, edges=None, directed=True) Bases:
object
-
N
(v, f_io=0)
-
add_edge
(e) add edge e and its vertices into the Graph possibly merging the associated graph_core components
-
add_edges
(edges) - Parameters
edges (
List
) –
-
add_vertex
(v) add vertex v into the Graph as a new component
-
component_class
-
connected
() returns the list of components
-
deg_avg
() the average degree of vertices
-
deg_max
() the maximum degree of vertices
-
deg_min
() the minimum degree of vertices
-
edges
()
-
eps
() the graph epsilon value (norm/order), average number of edges per vertex.
-
get_vertex_from_data
(data)
-
get_vertices_count
()
-
norm
() the norm of the graph (number of edges)
-
order
() the order of the graph (number of vertices)
-
path
(x, y, f_io=0, hook=None)
-
remove_edge
(e) remove edge e possibly spawning two new cores if the graph_core that contained e gets disconnected.
-
remove_vertex
(x) remove vertex v and all its edges.
-
vertices
() see graph_core
-
graphBase Module¶
-
class
graphistry.layout.graph.graphBase.
GraphBase
(vertices=None, edges=None, directed=True) Bases:
object
A connected graph of Vertex/Edge objects. A GraphBase is a component of a Graph that contains a connected set of Vertex and Edges.
- Attributes:
verticesPoset (Poset[Vertex]): the partially ordered set of vertices of the graph. edgesPoset (Poset[Edge]): the partially ordered set of edges of the graph. loops (set[Edge]): the set of loop edges (of degree 0). directed (bool): indicates if the graph is considered oriented or not.
-
N
(v, f_io=0)
-
add_edge
(e) add edge e. At least one of its vertex must belong to the graph, the other being added automatically.
-
add_single_vertex
(v) allow a GraphBase to hold a single vertex.
-
complement
(G)
-
constant_function
(value)
-
contract
(e)
-
deg_avg
() the average degree of vertices
-
deg_max
() the maximum degree of vertices
-
deg_min
() the minimum degree of vertices
-
dft
(start_vertex=None)
-
dijkstra
(x, f_io=0, hook=None) shortest weighted-edges paths between x and all other vertices by dijkstra’s algorithm with heap used as priority queue.
-
edges
(cond=None) generates an iterator over edges, with optional filter
-
eps
() the graph epsilon value (norm/order), average number of edges per vertex.
-
get_scs_with_feedback
(roots=None) Minimum FAS algorithm (feedback arc set) creating a DAG. Returns the set of strongly connected components (“scs”) by using Tarjan algorithm. These are maximal sets of vertices such that there is a path from each vertex to every other vertex. The algorithm performs a DFS from the provided list of root vertices. A cycle is of course a strongly connected component,but a strongly connected component can include several cycles. The Feedback Acyclic Set of edge to be removed/reversed is provided by marking the edges with a “feedback” flag. Complexity is O(V+E).
- Parameters
roots –
- Returns
-
leaves
() returns the list of leaves (vertices with no outward edges).
-
matrix
(cond=None) This associativity matrix is like the adjacency matrix but antisymmetric. Returns the associativity matrix of the graph component
- Parameters
cond – same a the condition function in vertices().
- Returns
array
-
norm
() The size of the edge poset (number of edges).
-
order
() the order of the graph (number of vertices)
-
partition
()
-
path
(x, y, f_io=0, hook=None) shortest path between vertices x and y by breadth-first descent, contrained by f_io direction if provided. The path is returned as a list of Vertex objects. If a hook function is provided, it is called at every vertex added to the path, passing the vertex object as argument.
-
remove_edge
(e) remove Edge e, asserting that the resulting graph is still connex.
-
remove_vertex
(x) remove Vertex x and all associated edges.
-
roots
() returns the list of roots (vertices with no inward edges).
-
spans
(vertices)
-
union_update
(G)
-
vertices
(cond=None) generates an iterator over vertices, with optional filter
vertex Module¶
-
class
graphistry.layout.graph.vertex.
Vertex
(data=None) Bases:
graphistry.layout.graph.vertexBase.VertexBase
Vertex class enhancing a VertexBase with graph-related features.
- Attributes
component (GraphBase): the component of connected vertices that contains this vertex. By default, a vertex belongs no component but when it is added in a graph, c points to the connected component in this graph. data (object) : an object associated with the vertex.
-
property
index
vertexBase Module¶
-
class
graphistry.layout.graph.vertexBase.
VertexBase
Bases:
object
Base class for vertices.
- Attributes
e (list[Edge]): list of edges associated with this vertex.
-
degree
() degree() : degree of the vertex (number of edges).
-
detach
() removes this vertex from all its edges and returns this list of edges.
-
e_dir
(dir) either e_in, e_out or all edges depending on provided direction parameter (>0 means outward).
-
e_from
(x) returns the Edge from vertex v directed toward this vertex.
-
e_in
() e_in() : list of edges directed toward this vertex.
-
e_out
() e_out(): list of edges directed outward this vertex.
-
e_to
(y) returns the Edge from this vertex directed toward vertex v.
-
e_with
(v) return the Edge with both this vertex and vertex v
-
neighbors
(direction=0) Returns the neighbors of this vertex. List of neighbor vertices in all directions (default) or in filtered f_io direction (>0 means outward).
- Parameters
direction –
0: parent and children
-1: parents
+1: children
- Returns
list of vertices