DAG - Directed Acyclic Graph API

A directed acyclic graph (DAG) API written in the crystal programming languge. This DAG implementation can be used for creating schedulers. E.g.: running multiple tasks which has predefined dependencies.

Installation

1. Add the dependency to your shard.yml:

   dependencies:
     dag:
       github: dseres/dag

2. Run shards install

Usage

Create a new Graph object. You can add and delete vertices and edges easily. If you enumarate the vertices with the #each method, the enumeration will be topologically sorted. The graph structure uses adjacency lists in the backend (implemented with Hash(K,V)), and you can store any hashable objects in it.

require "dag"
dag = Dag::Graph(Int32).new 
(1...10).each { |i| dag.add i}
dag.add_edge({1, 3} , {5, 9} , {8, 7} , {8, 6} , {6, 4} , {4, 3} , {4, 7})
dag.successors 4 # => [3,7]
dag.each { |v| p! v}
dag.to_a # => [1, 2, 5, 9, 8, 6, 4, 3, 7]

Contributing

1. Fork it (https://github.com/your-github-user/dag_cr/fork)
2. Create your feature branch (git checkout -b my-new-feature)
3. Commit your changes (git commit -am 'Add some feature')
4. Push to the branch (git push origin my-new-feature)
5. Create a new Pull Request

Contributors

• dseres - creator and maintainer