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authorAvneesh Saluja <asaluja@gmail.com>2013-03-28 18:28:16 -0700
committerAvneesh Saluja <asaluja@gmail.com>2013-03-28 18:28:16 -0700
commit3d8d656fa7911524e0e6885647173474524e0784 (patch)
tree81b1ee2fcb67980376d03f0aa48e42e53abff222 /klm/search/vertex_generator.hh
parentbe7f57fdd484e063775d7abf083b9fa4c403b610 (diff)
parent96fedabebafe7a38a6d5928be8fff767e411d705 (diff)
fixed conflicts
Diffstat (limited to 'klm/search/vertex_generator.hh')
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1 files changed, 99 insertions, 0 deletions
diff --git a/klm/search/vertex_generator.hh b/klm/search/vertex_generator.hh
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+#ifndef SEARCH_VERTEX_GENERATOR__
+#define SEARCH_VERTEX_GENERATOR__
+
+#include "search/edge.hh"
+#include "search/types.hh"
+#include "search/vertex.hh"
+#include "util/exception.hh"
+
+#include <boost/unordered_map.hpp>
+#include <boost/version.hpp>
+
+namespace lm {
+namespace ngram {
+class ChartState;
+} // namespace ngram
+} // namespace lm
+
+namespace search {
+
+class ContextBase;
+
+#if BOOST_VERSION > 104200
+// Parallel structure to VertexNode.
+struct Trie {
+ Trie() : under(NULL) {}
+
+ VertexNode *under;
+ boost::unordered_map<uint64_t, Trie> extend;
+};
+
+void AddHypothesis(ContextBase &context, Trie &root, const NBestComplete &end);
+
+#endif // BOOST_VERSION
+
+// Output makes the single-best or n-best list.
+template <class Output> class VertexGenerator {
+ public:
+ VertexGenerator(ContextBase &context, Vertex &gen, Output &nbest) : context_(context), gen_(gen), nbest_(nbest) {
+ gen.root_.InitRoot();
+ }
+
+ void NewHypothesis(PartialEdge partial) {
+ nbest_.Add(existing_[hash_value(partial.CompletedState())], partial);
+ }
+
+ void FinishedSearch() {
+#if BOOST_VERSION > 104200
+ Trie root;
+ root.under = &gen_.root_;
+ for (typename Existing::iterator i(existing_.begin()); i != existing_.end(); ++i) {
+ AddHypothesis(context_, root, nbest_.Complete(i->second));
+ }
+ existing_.clear();
+ root.under->SortAndSet(context_);
+#else
+ UTIL_THROW(util::Exception, "Upgrade Boost to >= 1.42.0 to use incremental search.");
+#endif
+ }
+
+ const Vertex &Generating() const { return gen_; }
+
+ private:
+ ContextBase &context_;
+
+ Vertex &gen_;
+
+ typedef boost::unordered_map<uint64_t, typename Output::Combine> Existing;
+ Existing existing_;
+
+ Output &nbest_;
+};
+
+// Special case for root vertex: everything should come together into the root
+// node. In theory, this should happen naturally due to state collapsing with
+// <s> and </s>. If that's the case, VertexGenerator is fine, though it will
+// make one connection.
+template <class Output> class RootVertexGenerator {
+ public:
+ RootVertexGenerator(Vertex &gen, Output &out) : gen_(gen), out_(out) {}
+
+ void NewHypothesis(PartialEdge partial) {
+ out_.Add(combine_, partial);
+ }
+
+ void FinishedSearch() {
+ gen_.root_.InitRoot();
+ NBestComplete completed(out_.Complete(combine_));
+ gen_.root_.SetEnd(completed.history, completed.score);
+ }
+
+ private:
+ Vertex &gen_;
+
+ typename Output::Combine combine_;
+ Output &out_;
+};
+
+} // namespace search
+#endif // SEARCH_VERTEX_GENERATOR__