class Zadt::Graph

Attributes

edges[R]

Which are connected by

value[RW]

Contains

vertices[R]

Made up of

Public Class Methods

help() click to toggle source
# File lib/zadt/HelpModules/Functionality/Graph/graph.rb, line 7
def self.help
  Graph.show_help_message
end
new() click to toggle source

init_v allows for initial vertices (not generally used)

# File lib/zadt/AbstractDataTypes/Graph/graph.rb, line 15
def initialize
  #@vertices is ALL vertices on the graph
  @vertices = []
  #@edges is ALL edges on the graph
  @edges = []
  @value = Hash.new
end

Private Class Methods

show_help_message() click to toggle source
# File lib/zadt/HelpModules/Functionality/Graph/graph.rb, line 13
def self.show_help_message
  Zadt::ADT::show_graph_help_message
end

Public Instance Methods

add_vertex() click to toggle source

Add a vertex

# File lib/zadt/AbstractDataTypes/Graph/graph.rb, line 24
def add_vertex
  vertex = Vertex.new
  @vertices << vertex
  vertex
end
break_connection(v1, v2) click to toggle source
# File lib/zadt/AbstractDataTypes/Graph/graph.rb, line 75
def break_connection(v1, v2)
  raise "First vertex does not exist" if !v1
  raise "Second vertex does not exist" if !v2

  if is_connected?(v1, v2)
    # Find edge
    edge = find_connection(v1, v2)
    # Remove edge from edges catalog
    @edges.delete(edge)
    #Remove edge from vertices
    v1.edges.delete(edge)
    v2.edges.delete(edge)
    v1.connections.delete(v2)
    v2.connections.delete(v1)
  else
    raise "Vertices are not connected"
  end
end
find_connection(v1, v2) click to toggle source

Find the edge connecting two vertices

# File lib/zadt/AbstractDataTypes/Graph/graph.rb, line 61
def find_connection(v1, v2)
  raise "not a vertex" unless v1.is_a?(Vertex) && v2.is_a?(Vertex)
  raise "Vertices not connected" if !is_connected?(v1, v2)
  connection = v1.edges.select {|edge| edge.connection.include?(v2)}
  raise "Error finding connection" if connection.length > 1
  connection.first
end
help() click to toggle source
# File lib/zadt/HelpModules/Functionality/Graph/graph.rb, line 3
def help
  Graph.help
end
is_connected?(v1, v2) click to toggle source

Returns whether two vertices are connected

# File lib/zadt/AbstractDataTypes/Graph/graph.rb, line 70
def is_connected?(v1, v2)
  raise "not a vertex" unless v1.is_a?(Vertex) && v2.is_a?(Vertex)
  v1.connections.include?(v2)
end
make_connection(v1, v2) click to toggle source

Make an edge between two vertices

# File lib/zadt/AbstractDataTypes/Graph/graph.rb, line 46
def make_connection(v1, v2)
  raise "not a vertex" unless v1.is_a?(Vertex) && v2.is_a?(Vertex)
  raise "already connected" if is_connected?(v1, v2)
  # Make new edge
  edge = Edge.new(v1, v2)
  # Connect the two using the vertex method "connect"
  v1.connect(v2, edge)
  v2.connect(v1, edge)

  # Add to edge catalog
  @edges << edge
  edge
end
remove_vertex(vertex) click to toggle source

Remove a vertex

# File lib/zadt/AbstractDataTypes/Graph/graph.rb, line 31
def remove_vertex(vertex)
  # The vertex must exist
  raise "not a vertex" unless vertex.is_a?(Vertex)
  if !vertex
    raise "Vertex does not exist"
  # The vertex must not be connected to anything
  elsif !vertex.connections.empty?
    raise "Vertex has edges.  Break them first."
  # If it exists and isn't connected, delete it
  else
    @vertices.delete(vertex)
  end
end