FloydWarshall

Implements the Floyd-Warshall algorithm to find the shortest paths between all pairs of nodes.

Installation

Add this line to your application's Gemfile:

gem 'floyd_warshall'

And then execute:

$ bundle install

Or install it yourself as:

$ gem install floyd_warshall

Usage

Create a graph and the adjacency matrix

nodes = ['A', 'B', 'C', 'D', 'E']

graph = WeightedGraph::PositiveWeightedGraph.new
graph.add_undirected_edge('A', 'B', 2)
graph.add_undirected_edge('B', 'C', 2)
graph.add_undirected_edge('C', 'D', 2)
graph.add_undirected_edge('A', 'D', 10)
graph.add_undirected_edge('B', 'E', 1)

matrix = AdjacencyMatrix::Matrix.new(nodes, graph)

Create the optimizer

optimizer = FloydWarshall::Optimizer.new(matrix)

Running

The run method returns an AdjacencyMatrix::Matrix object which allows you to access individual edge values. See the adjacency_matrix gem for more info.

result = optimizer.run

result.get('A', 'D')
#=> 4

Development

After checking out the repo, run bin/setup to install dependencies. Then, run rake spec to run the tests. You can also run bin/console for an interactive prompt that will allow you to experiment.

To install this gem onto your local machine, run bundle exec rake install. To release a new version, update the version number in version.rb, and then run bundle exec rake release, which will create a git tag for the version, push git commits and tags, and push the .gem file to rubygems.org.

Contributing

Bug reports and pull requests are welcome on GitHub at https://github.com/code-fabrik/floyd_warshall. This project is intended to be a safe, welcoming space for collaboration, and contributors are expected to adhere to the code of conduct.

License

The gem is available as open source under the terms of the MIT License.

Code of Conduct

Everyone interacting in the FloydWarshall project's codebases, issue trackers, chat rooms and mailing lists is expected to follow the code of conduct.