Class: Graph

Inherits:
Object show all
Defined in:
lib/graph.rb

Overview

Graph models directed graphs and subgraphs and outputs in graphviz’s dot format.

Defined Under Namespace

Classes: Attribute, CompoundAttribute, Edge, Node, Thingy

Constant Summary collapse

VERSION =

:nodoc:

"2.8.0"
LIGHT_COLORS =

:stopdoc:

%w(gray lightblue lightcyan lightgray lightpink
lightslategray lightsteelblue white)
BOLD_COLORS =

WTF – can’t be %w() because of a bug in rcov

["black", "brown", "mediumblue", "blueviolet",
"orange", "magenta", "darkgreen", "maroon",
"violetred", "purple", "greenyellow", "deeppink",
"midnightblue", "firebrick", "darkturquoise",
"mediumspringgreen", "chartreuse", "navy",
"lightseagreen", "chocolate", "lawngreen", "green",
"indigo", "darkgoldenrod", "darkviolet", "red",
"springgreen", "saddlebrown", "mediumvioletred",
"goldenrod", "tomato", "cyan", "forestgreen",
"darkorchid", "crimson", "coral", "deepskyblue",
"seagreen", "peru", "turquoise", "orangered",
"dodgerblue", "sienna", "limegreen", "royalblue",
"darkorange", "blue"]
COLOR_SCHEME_MAX =

Defines the brewer color schemes and the maximum number of colors in each set.

{
  :accent   => 8,  :blues    => 9,  :brbg     => 11, :bugn     => 9,
  :dark2    => 8,  :gnbu     => 9,  :greens   => 9,  :greys    => 9,
  :oranges  => 9,  :orrd     => 9,  :paired   => 12, :pastel1  => 9,
  :pastel2  => 8,  :piyg     => 11, :prgn     => 11, :pubu     => 9,
  :pubugn   => 9,  :puor     => 11, :purd     => 9,  :purples  => 9,
  :rdbu     => 11, :rdgy     => 11, :rdylbu   => 11, :rdylgn   => 11,
  :reds     => 9,  :set1     => 9,  :set2     => 8,  :set3     => 12,
  :spectral => 11, :ylgn     => 9,  :ylgnbu   => 9,  :ylorbr   => 9,
  :ylorrd   => 9
}
SHAPES =
%w(Mcircle Mdiamond Msquare box box3d circle component
diamond doublecircle doubleoctagon egg ellipse folder
hexagon house invhouse invtrapezium invtriangle none
note octagon parallelogram pentagon plaintext point
polygon rect rectangle septagon square tab trapezium
triangle tripleoctagon)
STYLES =
%w(dashed dotted solid invis bold filled diagonals rounded)
ARROW_RE =
/(?:o?[lr]?(?:box|crow|diamond|dot|inv|none|normal|tee|vee)){1,4}/
ARROWS =
%w(box crow diamond dot inv none normal tee vee)

Instance Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(name = nil, graph = nil, &block) ⇒ Graph

Creates a new graph object. Optional name and parent graph are available. Also takes an optional block for DSL-like use.



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# File 'lib/graph.rb', line 137

def initialize name = nil, graph = nil, &block
  @name = name
  @graph = graph
  graph << self if graph
  @nodes_order = []
  @nodes  = Hash.new { |h,k| @nodes_order << k; h[k] = Node.new self, k }
  @edges_order = []
  @edges  = Hash.new { |h,k|
    h[k] = Hash.new { |h2, k2|
      @edges_order << [k, k2]
      h2[k2] = Edge.new self, self[k], self[k2]
    }
  }
  @graph_attribs = []
  @node_attribs  = []
  @edge_attribs  = []
  @subgraphs     = []

  self.scheme = graph.scheme if graph
  node_attribs << scheme if scheme

  instance_eval(&block) if block
end

Instance Attribute Details

#edge_attribsObject (readonly)

Global attributes for edges in this graph.



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# File 'lib/graph.rb', line 102

def edge_attribs
  @edge_attribs
end

#edgesObject (readonly)

The hash of hashes of edges in this graph. Use #[] or #node to create edges.



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# File 'lib/graph.rb', line 107

def edges
  @edges
end

#edges_orderObject (readonly)

:nodoc:



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# File 'lib/graph.rb', line 131

def edges_order
  @edges_order
end

#graphObject

A parent graph, if any. Only used for subgraphs.



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# File 'lib/graph.rb', line 91

def graph
  @graph
end

#graph_attribsObject (readonly)

Global attributes for this graph.



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# File 'lib/graph.rb', line 112

def graph_attribs
  @graph_attribs
end

#nameObject

The name of the graph. Optional for graphs and subgraphs. Prefix the name of a subgraph with “cluster” for subgraph that is boxed.



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# File 'lib/graph.rb', line 97

def name
  @name
end

#node_attribsObject (readonly)

Global attributes for nodes in this graph.



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# File 'lib/graph.rb', line 117

def node_attribs
  @node_attribs
end

#nodesObject (readonly)

The hash of nodes in this graph. Use #[] or #node to create nodes.



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# File 'lib/graph.rb', line 122

def nodes
  @nodes
end

#nodes_orderObject (readonly)

TODO: remove if/when I drop 1.8 support.



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# File 'lib/graph.rb', line 130

def nodes_order
  @nodes_order
end

#schemeObject

Shortcut method to create a new colorscheme Attribute instance. If passed n, name must match one of the brewer color scheme names and it will generate accessors for each fillcolor as well as push the colorscheme onto the node_attribs.



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# File 'lib/graph.rb', line 219

def scheme
  @scheme
end

#subgraphsObject (readonly)

An array of subgraphs.



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# File 'lib/graph.rb', line 127

def subgraphs
  @subgraphs
end

Class Method Details

.escape_label(s) ⇒ Object



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# File 'lib/graph.rb', line 293

def self.escape_label s
  s = s.gsub(/\n/, '\n').gsub(/\"/, '\\\"')
  if s[0] == ?< and s[-1] == ?> then
    s
  else
    "\"#{s}\""
  end
end

Instance Method Details

#<<(subgraph) ⇒ Object

Push a subgraph into the current graph. Sets the subgraph’s graph to self.



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# File 'lib/graph.rb', line 164

def << subgraph
  subgraphs << subgraph
  subgraph.graph = self
end

#[](name) ⇒ Object

Access a node by name



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# File 'lib/graph.rb', line 172

def [] name
  nodes[name]
end

#arrowhead(shape) ⇒ Object

Shortcut method for creating an arrowhead attribute.

Raises:

  • (ArgumentError)


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# File 'lib/graph.rb', line 179

def arrowhead shape
  raise ArgumentError, "Bad arrow shape: #{shape}" unless shape =~ ARROW_RE
  Attribute.new "arrowhead = #{shape}"
end

#arrowsize(size) ⇒ Object

Shortcut method for creating an arrowsize attribute.



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# File 'lib/graph.rb', line 195

def arrowsize size
  Attribute.new "arrowsize = #{size}"
end

#arrowtail(shape) ⇒ Object

Shortcut method for creating an arrowtail attribute.

Raises:

  • (ArgumentError)


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# File 'lib/graph.rb', line 187

def arrowtail shape
  raise ArgumentError, "Bad arrow shape: #{shape}" unless shape =~ ARROW_RE
  Attribute.new "arrowtail = #{shape}"
end

#boxesObject

Shortcut method to set the global node attributes to use boxes.



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# File 'lib/graph.rb', line 202

def boxes
  node_attribs << shape("box")
end

#cluster(name, &block) ⇒ Object

Shortcut method to create a clustered subgraph in the current graph. Use with the top-level digraph method in block form for a graph DSL.



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# File 'lib/graph.rb', line 371

def cluster name, &block
  subgraph "cluster_#{name}", &block
end

#color(color) ⇒ Object

Shortcut method to create a new color Attribute instance.



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# File 'lib/graph.rb', line 209

def color color
  Attribute.new "color = #{color}"
end

#colorscheme(name, n = nil) ⇒ Object

Shortcut method to create and set the graph to use a colorscheme.



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# File 'lib/graph.rb', line 224

def colorscheme name, n = nil
  self.scheme = Attribute.new "colorscheme = #{name}#{n}"
  max = COLOR_SCHEME_MAX[name.to_sym]

  node_attribs << scheme if max

  scheme
end

#delete_node(node_name) ⇒ Object

Deletes a node from the graph



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# File 'lib/graph.rb', line 377

def delete_node node_name
  nodes.delete node_name
  nodes_order.delete node_name
end

#edge(*names) ⇒ Object

Define one or more edges.

edge "a", "b", "c", ...

is equivalent to:

edge "a", "b"
edge "b", "c"
...


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# File 'lib/graph.rb', line 250

def edge(*names)
  last = nil
  names.each_cons(2) do |from, to|
    last = self[from][to]
  end
  last
end

#fillcolor(n) ⇒ Object

Shortcut method to create a new fillcolor Attribute instance.



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# File 'lib/graph.rb', line 274

def fillcolor n
  Attribute.new "fillcolor = #{n}"
end

#font(name) ⇒ Object

Shortcut method to create a new font Attribute instance. You can pass in both the name and an optional font size.



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# File 'lib/graph.rb', line 282

def font name
  Attribute.new "fontname = #{name.inspect}"
end

#fontsize(size) ⇒ Object

Shortcut method to create a new fontsize Attribute instance.



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# File 'lib/graph.rb', line 289

def fontsize size
  Attribute.new "fontsize = #{size}"
end

#invertObject

Creates a new Graph whose edges point the other direction.



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# File 'lib/graph.rb', line 261

def invert
  result = self.class.new
  edges.each do |from, h|
    h.each do |to, edge|
      result[to][from]
    end
  end
  result
end

#label(name) ⇒ Object

Shortcut method to set the graph’s label. Usually used with subgraphs.



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# File 'lib/graph.rb', line 305

def label name
  graph_attribs << "label = #{Graph.escape_label name}"
end

#node(name, label = nil) ⇒ Object

Access a node by name, supplying an optional label



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# File 'lib/graph.rb', line 312

def node name, label = nil
  n = nodes[name]
  n.label label if label
  n
end

#orient(dir = "TB") ⇒ Object

Shortcut method to specify the orientation of the graph. Defaults to the graphviz default “TB”.



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# File 'lib/graph.rb', line 322

def orient dir = "TB"
  graph_attribs << "rankdir = #{dir}"
end

#rotate(dir = "LR") ⇒ Object

Shortcut method to specify the orientation of the graph. Defaults to “LR”.



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# File 'lib/graph.rb', line 329

def rotate dir = "LR"
  orient dir
end

#save(path, type = nil) ⇒ Object

Saves out both a dot file to path and an image for the specified type. Specify type as nil to skip exporting an image.



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# File 'lib/graph.rb', line 337

def save path, type = nil
  File.open "#{path}.dot", "w" do |f|
    f.puts self.to_s
  end
  system "dot -T#{type} #{path}.dot > #{path}.#{type}" if type
end

#shape(shape) ⇒ Object

Shortcut method to create a new shape Attribute instance.



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# File 'lib/graph.rb', line 347

def shape shape
  Attribute.new "shape = #{shape}"
end

#style(name) ⇒ Object

Shortcut method to create a new style Attribute instance.



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# File 'lib/graph.rb', line 354

def style name
  Attribute.new "style = #{name}"
end

#subgraph(name = nil, &block) ⇒ Object

Shortcut method to create a subgraph in the current graph. Use with the top-level digraph method in block form for a graph DSL.



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# File 'lib/graph.rb', line 362

def subgraph name = nil, &block
  Graph.new name, self, &block
end

#to_sObject

Outputs a graphviz graph.



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# File 'lib/graph.rb', line 385

def to_s
  result = []

  type = graph ? "subgraph " : "digraph "
  type << "\"#{name}\"" if name and !name.empty?
  result << type
  result << "  {"

  graph_attribs.each do |line|
    result << "    #{line};"
  end

  unless node_attribs.empty? then
    result << "    node [ #{node_attribs.join(", ")} ];"
  end

  unless edge_attribs.empty? then
    result << "    edge [ #{edge_attribs.join(", ")} ];"
  end

  subgraphs.each do |line|
    result << "    #{line};"
  end

  nodes_order.each do |name|
    node = nodes[name]
    result << "    #{node};" if graph or node.attributes? or node.orphan?
  end

  edges_order.uniq.each do |(from, to)|
    edge = edges[from][to]
    result << "    #{edge};"
  end

  result << "  }"
  result.join "\n"
end