diff options
Diffstat (limited to 'hg.rb')
| -rw-r--r-- | hg.rb | 78 |
1 files changed, 31 insertions, 47 deletions
@@ -8,17 +8,20 @@ module HG class HG::Node - attr_accessor :id, :outgoing, :incoming, :score + attr_accessor :id, :symbol, :left, :right, :outgoing, :incoming, :score - def initialize id=nil, cat=nil, outgoing=[], incoming=[], score=nil - @id = id + def initialize id=nil, symbol='', span=[-1,-1], outgoing=[], incoming=[], score=nil + @id = id + @symbol = symbol + @left = span[0] + @right = span[1] @outgoing = outgoing @incoming = incoming - @score = nil + @score = score end def to_s - "Node<id:#{@id}, outgoing:#{@outgoing.size}, incoming:#{@incoming.size}>" + "Node<id=#{@id}, symbol='#{symbol}', span=(#{@left},#{@right}), outgoing:#{@outgoing.size}, incoming:#{@incoming.size}>" end end @@ -41,20 +44,20 @@ class HG::Hypergraph end def to_s - "Hypergraph<nodes:#{@nodes.size}, edges:#{@edges.size}, arity:#{arity}>" + "Hypergraph<nodes:#{@nodes.size}, edges:#{@edges.size}, arity=#{arity}>" end end class HG::Hyperedge attr_accessor :head, :tails, :score, :f, :mark, :rule - def initialize head=nil, tails=[], score=0.0, f=SparseVector.new, rule=nil + def initialize head=Node.new, tails=[], score=0.0, f=SparseVector.new, rule=nil @head = head @tails = tails @score = score @f = f @mark = 0 - @rule = (rule ? Grammar::Rule.from_s(rule) : nil) + @rule = (rule.class==String ? Grammar::Rule.from_s(rule) : rule) end def arity @@ -66,7 +69,7 @@ class HG::Hyperedge end def to_s - "Hyperedge<head:\"#{@head.id}\", rule:\"#{@rule.to_s}, \"tails:#{@tails.map{|n|n.id}}, arity:#{arity}, score:#{@score}, f:#{f.to_s}, mark:#{@mark}>" + "Hyperedge<head=#{@head.id}, rule:'#{@rule.to_s}', tails=#{@tails.map{|n|n.id}}, arity=#{arity}, score=#{@score}, f=#{f.to_s}, mark=#{@mark}>" end end @@ -124,27 +127,6 @@ def HG::viterbi_path hypergraph, root, semiring=ViterbiSemiring.new return best_path, toposorted.last.score end -def HG::viterbi_string hypergraph, root, semiring=ViterbiSemiring.new - toposorted = topological_sort hypergraph.nodes - init toposorted, semiring, root - s = '' - toposorted.each { |n| - best_s = nil - n.incoming.each { |e| - s = semiring.one - e.tails.each { |m| - s = semiring.multiply.call(s, m.score) - } - if n.score < semiring.multiply.call(s, e.score) # ViterbiSemiring add - best_s = e.e - end - n.score = semiring.add.call(n.score, semiring.multiply.call(s, e.score)) - } - s += best_s if best_s - } - return s, toposorted.last.score -end - def HG::all_paths hypergraph, root toposorted = topological_sort hypergraph.nodes paths = [[]] @@ -162,6 +144,22 @@ def HG::all_paths hypergraph, root return paths end +def HG::derive path, cur, carry + edge = path.select { |e| e.head.symbol==cur.symbol \ + && e.head.left==cur.left \ + && e.head.right==cur.right }.first + j = 0 + edge.rule.target.each { |i| + if i.class == Grammar::NT + derive path, edge.tails[j], carry + j += 1 + else + carry << i + end + } + return carry +end + def HG::read_hypergraph_from_json fn, semiring=RealSemiring.new, log_weights=false nodes = [] edges = [] @@ -169,7 +167,7 @@ def HG::read_hypergraph_from_json fn, semiring=RealSemiring.new, log_weights=fal h = JSON.parse File.new(fn).read w = SparseVector.from_h h['weights'] h['nodes'].each { |x| - n = Node.new x['id'] + n = Node.new x['id'], x['symbol'], x['span'] nodes << n nodes_by_id[n.id] = n } @@ -181,9 +179,9 @@ def HG::read_hypergraph_from_json fn, semiring=RealSemiring.new, log_weights=fal x['rule']) if x['f'] if log_weights - e.weight = Math.exp(w.dot(e.f)) + e.score = Math.exp(w.dot(e.f)) else - e.weight = w.dot(e.f) + e.score = w.dot(e.f) end end e.tails.each { |m| @@ -195,20 +193,6 @@ def HG::read_hypergraph_from_json fn, semiring=RealSemiring.new, log_weights=fal return Hypergraph.new(nodes, edges), nodes_by_id end -def HG::derive path, cur, carry - edge = path.select { |e| e.rule.lhs.symbol==cur.symbol \ - && e.rule.lhs.left==cur.left \ - && e.rule.lhs.right==cur.right }.first - edge.rule.target.each { |i| - if i.class == Grammar::NT - derive path, i, carry - else - carry << i - end - } - return carry -end - end #module |