SimpleGraph

gem 'simple_graph'

require "simple_graph"

# Creating a new, empty graph
graph = SimpleGraph::Graph.new

# Adding nodes to the graph
# Creates a empty node containing only a autogenerated identifier
# Returns a graph-unique identifier for the newly created node
foo = graph.add_node()
# IDs can also be set manually
graph.add_node(id: "Kevin")
# Graphs can also hold arbitrary information in the 'data' hash
stuff = {
  age: 21,
  depression: true
}
bar = graph.add_node(id: "Igor", data: stuff)

# Edges can be created by passing the two node IDs to the connect_nodes method
graph.connect_nodes(foo, "Kevin")

# Paths between two nodes can be found by breadth-first search
paths = graph.find_paths(foo, bar)

# Retrieving info about the graph
graph.nodes # Lists all of the nodes in the graph
graph.node_count # Returns the amount of nodes in the graph
graph.node_ids # Array of node identifiers in the graph
graph.are_connected?(foo, bar) # Checks whether two nodes are connected by an Edge
graph.include?("Kevin") # Checks whether the graph includes a node with the given ID

# Graphs can be written to files in the DOT format to be used with Graphviz
# Note that the node ID will be used for labels
File.write("test.dot", graph.to_dot_string)

# Export a graph to a JSON file
File.write("output.json", graph.to_json)

# Import a graph from a JSON file
graph.load_from_json(File.read("input.json"))