add nodes module

[yaslena]

Module description
This module adds new nodes to an existing graph object that has already been generated.

Inputs

• iterable container (list, dict, set...)
• new graph

Graph types
All graph types will need this module.

Example code
In the Jupyter notebook there is one example of how this can be done (cell 199-208): https://github.com/DHARPA-Project/NetworkXAnalysis/blob/master/ReviewsNXPandas.ipynb

add nodes:
new_data = new_nodes_unique.set_index('Id').to_dict('index').items()
A.add_nodes_from(new_data)

add edges (by adding a new graph (B) to the old graph(A)):
A.add_edges_from(B.edges(data=True))
General:
Graph.add_nodes_from(nodes_for_adding, **attr)

Parameters
nodes_for_adding: iterable container
A container of nodes (list, dict, set, etc.). OR A container of (node, attribute dict) tuples. Node attributes are updated using the attribute dict.