nx-parallel

nx-parallel is a NetworkX backend that uses joblib for parallelization. This project aims to provide parallelized implementations of various NetworkX functions to improve performance. Refer NetworkX backends documentation to learn more about the backend architecture in NetworkX.

Algorithms in nx-parallel

• all_pairs_all_shortest_paths
• all_pairs_bellman_ford_path
• all_pairs_bellman_ford_path_length
• all_pairs_dijkstra
• all_pairs_dijkstra_path
• all_pairs_dijkstra_path_length
• all_pairs_node_connectivity
• all_pairs_shortest_path
• all_pairs_shortest_path_length
• approximate_all_pairs_node_connectivity
• betweenness_centrality
• closeness_vitality
• edge_betweenness_centrality
• is_reachable
• johnson
• local_efficiency
• node_redundancy
• number_of_isolates
• square_clustering
• tournament_is_strongly_connected

Script used to generate the above list

import _nx_parallel as nxp
d = nxp.get_funcs_info() # temporarily add `from .update_get_info import *` to _nx_parallel/__init__.py
for func in d:
    print(f"- [{func}]({d[func]['url']})")

Installation

You can install the stable version of nx-parallel using pip or conda:

pip install nx-parallel

conda install nx-parallel

For more, see INSTALL.md.

Backend usage

You can run your networkx code with nx-parallel backend by:

export NETWORKX_AUTOMATIC_BACKENDS="parallel" && python nx_code.py

Note that for all functions inside nx_code.py that do not have an nx-parallel implementation their original networkx implementation will be executed. You can also use the nx-parallel backend in your code for only some specific function calls in the following ways:

import networkx as nx
import nx_parallel as nxp

# enabling networkx's config for nx-parallel
nx.config.backends.parallel.active = True

# setting `n_jobs` (by default, `n_jobs=None`)
nx.config.backends.parallel.n_jobs = 4

G = nx.path_graph(4)
H = nxp.ParallelGraph(G)

# method 1 : passing ParallelGraph object in networkx function (Type-based dispatching)
nx.betweenness_centrality(H)

# method 2 : using the 'backend' kwarg
nx.betweenness_centrality(G, backend="parallel")

# method 3 : using nx-parallel implementation with networkx object
nxp.betweenness_centrality(G)

# method 4 : using nx-parallel implementation with ParallelGraph object
nxp.betweenness_centrality(H)

For more on how to play with configurations in nx-parallel refer the Config.md! Additionally, refer the NetworkX's official backend and config docs for more on functionalities provided by networkx for backends and configs like logging, backend_priority, etc. Another way to configure nx-parallel is by using joblib.parallel_config.

Notes

1. Some functions in networkx have the same name but different implementations, so to avoid these name conflicts at the time of dispatching networkx differentiates them by specifying the name parameter in the _dispatchable decorator of such algorithms. So, method 3 and method 4 are not recommended. But, you can use them if you know the correct name. For example:

   # using `name` parameter - nx-parallel as an independent package
   
   # run the parallel implementation in `connectivity/connectivity`
   nxp.all_pairs_node_connectivity(H)
   
   # runs the parallel implementation in `approximation/connectivity`
   nxp.approximate_all_pairs_node_connectivity(H)

   Also, if you are using nx-parallel as a backend then mentioning the subpackage to which the algorithm belongs is recommended to ensure that networkx dispatches to the correct implementation. For example:

   # with subpackage - nx-parallel as a backend
   nx.all_pairs_node_connectivity(H)
   nx.approximation.all_pairs_node_connectivity(H)

2. Right now there isn't much difference between nx.Graph and nxp.ParallelGraph so method 3 would work fine but it is not recommended because in the future that might not be the case.

Feel free to contribute to nx-parallel. You can find the contributing guidelines here. If you'd like to implement a feature or fix a bug, we'd be happy to review a pull request. Please make sure to explain the changes you made in the pull request description. And feel free to open issues for any problems you face, or for new features you'd like to see implemented.

This project is managed under the NetworkX organisation, so the code of conduct of NetworkX applies here as well.

All code in this repository is available under the Berkeley Software Distribution (BSD) 3-Clause License (see LICENSE).

Thank you :)