At Eric's behest, I'm releasing the code that I used to generate the ABC colored graphs that I posted about earlier. It allows for quick and dirty (I prefer the term "clean") graphs through Graphviz's dot language.
graph = Graph.new graph["from"] << "to" puts graph.to_s
when processed becomes:
It has other bells and whistles, when a plain graph just won't do, but the emphasis is on simplicity and getting things done. Best of all, it is only 65 lines long. Code after the cut...
#!/usr/local/bin/ruby -w
class Graph < Hash
attr_reader :attribs
attr_reader :prefix
attr_reader :order
def initialize
super { |h,k| h[k] = [] }
@prefix = []
@attribs = Hash.new { |h,k| h[k] = [] }
@order = []
end
def []=(key, val)
@order << key unless self.has_key? key
super(key, val)
end
def each_pair
@order.each do |from|
self[from].each do |to|
yield(from, to)
end
end
end
def invert
result = self.class.new
each_pair do |from, to|
result[to] << from
end
result
end
def counts
result = Hash.new(0)
each_pair do |from, to|
result[from] += 1
end
result
end
def keys_by_count
counts.sort_by { |x,y| y }.map {|x| x.first }
end
def to_s
result = []
result << "digraph absent"
result << " {"
@prefix.each do |line|
result << line
end
@attribs.sort.each do |node, attribs|
result << " #{node.inspect} [ #{attribs.join(',')} ]"
end
each_pair do |from, to|
result << " #{from.inspect} -> #{to.inspect};"
end
result << " }"
result.join("\n")
end
end
Very nice. Would you consider registering this on RubyForge and make it a gem? It would also be cool if you added integration with dot so you can do something like graph.write("some/file.png")
[absolutely--but do know there is a very bloated graphviz library on RAA already if you can't wait]