# Functions¶

Functional interface to graph methods and assorted utilities.

## Graph¶

 degree(G[, nbunch, t]) Return the degree of a node or nodes at time t. degree_histogram(G[, t]) Return a list of the frequency of each degree value. density(G[, t]) Return the density of a graph at timestamp t. create_empty_copy(G[, with_data]) Return a copy of the graph G with all of the edges removed. is_directed(G) Return True if graph is directed. add_star(G, nodes, t, **attr) Add a star at time t. add_path(G, nodes, t, **attr) Add a path at time t. add_cycle(G, nodes, t, **attr) Add a cycle at time t.

## Nodes¶

 nodes(G[, t]) Return a list of the nodes in the graph at a given snapshot. number_of_nodes(G[, t]) Return the number of nodes in the t snpashot of a dynamic graph. all_neighbors(graph, node[, t]) Returns all of the neighbors of a node in the graph at time t. non_neighbors(graph, node[, t]) Returns the non-neighbors of the node in the graph at time t.

## Interactions¶

 interactions(G[, nbunch, t]) Return the list of edges present in a given snapshot. number_of_interactions(G[, u, v, t]) Return the number of edges between two nodes at time t. non_interactions(graph[, t]) Returns the non-existent edges in the graph at time t.

## Freezing graph structure¶

 freeze(G) Modify graph to prevent further change by adding or removing nodes or edges. is_frozen(G) Return True if graph is frozen.

## Snapshots and Interaction Stream¶

 stream_interactions(G) Generate a temporal ordered stream of interactions. time_slice(G, t_from[, t_to]) Return an iterator for (node, degree) at time t. temporal_snapshots_ids(G) Return the ordered list of snapshot ids present in the dynamic graph. interactions_per_snapshots(G[, t]) Return the number of interactions within snapshot t. inter_event_time_distribution(G[, u, v]) Return the distribution of inter event time.