add generative word alignment model and primitive EM trainer. Model 1 and HMM are supported, without NULL source words

1 files changed, 0 insertions, 113 deletions

diff --git a/decoder/lexcrf.cc b/decoder/lexcrf.cc
deleted file mode 100644
index b0e03c69..00000000
--- a/decoder/lexcrf.cc
+++ /dev/null
@@ -1,113 +0,0 @@
-#include "lexcrf.h"
-
-#include <iostream>
-
-#include "filelib.h"
-#include "hg.h"
-#include "tdict.h"
-#include "grammar.h"
-#include "sentence_metadata.h"
-
-using namespace std;
-
-struct LexicalCRFImpl {
-  LexicalCRFImpl(const boost::program_options::variables_map& conf) :
-      use_null(conf.count("lexcrf_use_null") > 0),
-      kXCAT(TD::Convert("X")*-1),
-      kNULL(TD::Convert("<eps>")),
-      kBINARY(new TRule("[X] ||| [X,1] [X,2] ||| [1] [2]")),
-      kGOAL_RULE(new TRule("[Goal] ||| [X,1] ||| [1]")) {
-    vector<string> gfiles = conf["grammar"].as<vector<string> >();
-    assert(gfiles.size() == 1);
-    ReadFile rf(gfiles.front());
-    TextGrammar *tg = new TextGrammar;
-    grammar.reset(tg);
-    istream* in = rf.stream();
-    int lc = 0;
-    bool flag = false;
-    while(*in) {
-      string line;
-      getline(*in, line);
-      if (line.empty()) continue;
-      ++lc;
-      TRulePtr r(TRule::CreateRulePhrasetable(line));
-      tg->AddRule(r);
-      if (lc %   50000 == 0) { cerr << '.'; flag = true; }
-      if (lc % 2000000 == 0) { cerr << " [" << lc << "]\n"; flag = false; }
-    }
-    if (flag) cerr << endl;
-    cerr << "Loaded " << lc << " rules\n";
-  }
-
-  void BuildTrellis(const Lattice& lattice, const SentenceMetadata& smeta, Hypergraph* forest) {
-    const int e_len = smeta.GetTargetLength();
-    assert(e_len > 0);
-    const int f_len = lattice.size();
-    // hack to tell the feature function system how big the sentence pair is
-    const int f_start = (use_null ? -1 : 0);
-    int prev_node_id = -1;
-    for (int i = 0; i < e_len; ++i) {  // for each word in the *target*
-      Hypergraph::Node* node = forest->AddNode(kXCAT);
-      const int new_node_id = node->id_;
-      for (int j = f_start; j < f_len; ++j) { // for each word in the source
-        const WordID src_sym = (j < 0 ? kNULL : lattice[j][0].label);
-        const GrammarIter* gi = grammar->GetRoot()->Extend(src_sym);
-        if (!gi) {
-          cerr << "No translations found for: " << TD::Convert(src_sym) << "\n";
-          abort();
-        }
-        const RuleBin* rb = gi->GetRules();
-        assert(rb);
-        for (int k = 0; k < rb->GetNumRules(); ++k) {
-          TRulePtr rule = rb->GetIthRule(k);
-          Hypergraph::Edge* edge = forest->AddEdge(rule, Hypergraph::TailNodeVector());
-          edge->i_ = j;
-          edge->j_ = j+1;
-          edge->prev_i_ = i;
-          edge->prev_j_ = i+1;
-          edge->feature_values_ += edge->rule_->GetFeatureValues();
-          forest->ConnectEdgeToHeadNode(edge->id_, new_node_id);
-        }
-      }
-      if (prev_node_id >= 0) {
-        const int comb_node_id = forest->AddNode(kXCAT)->id_;
-        Hypergraph::TailNodeVector tail(2, prev_node_id);
-        tail[1] = new_node_id;
-        Hypergraph::Edge* edge = forest->AddEdge(kBINARY, tail);
-        forest->ConnectEdgeToHeadNode(edge->id_, comb_node_id);
-        prev_node_id = comb_node_id;
-      } else {
-        prev_node_id = new_node_id;
-      }
-    }
-    Hypergraph::TailNodeVector tail(1, forest->nodes_.size() - 1);
-    Hypergraph::Node* goal = forest->AddNode(TD::Convert("Goal")*-1);
-    Hypergraph::Edge* hg_edge = forest->AddEdge(kGOAL_RULE, tail);
-    forest->ConnectEdgeToHeadNode(hg_edge, goal);
-  }
-
- private:
-  const bool use_null;
-  const WordID kXCAT;
-  const WordID kNULL;
-  const TRulePtr kBINARY;
-  const TRulePtr kGOAL_RULE;
-  GrammarPtr grammar;
-};
-
-LexicalCRF::LexicalCRF(const boost::program_options::variables_map& conf) :
-  pimpl_(new LexicalCRFImpl(conf)) {}
-
-bool LexicalCRF::Translate(const string& input,
-                      SentenceMetadata* smeta,
-                      const vector<double>& weights,
-                      Hypergraph* forest) {
-  Lattice lattice;
-  LatticeTools::ConvertTextToLattice(input, &lattice);
-  smeta->SetSourceLength(lattice.size());
-  pimpl_->BuildTrellis(lattice, *smeta, forest);
-  forest->is_linear_chain_ = true;
-  forest->Reweight(weights);
-  return true;
-}
-