add Bilingual LM class

moses/FF/bilingual-lm/BilingualLM.cpp

@@ -0,0 +1,74 @@
+#include <vector>
+#include "BilingualLM.h"
+#include "moses/ScoreComponentCollection.h"
+#include "moses/Hypothesis.h"
+
+using namespace std;
+
+namespace Moses
+{
+int BilingualLMState::Compare(const FFState& other) const
+{
+  const BilingualLMState &otherState = static_cast<const BilingualLMState&>(other);
+
+  if (m_targetLen == otherState.m_targetLen)
+    return 0;
+  return (m_targetLen < otherState.m_targetLen) ? -1 : +1;
+}
+
+////////////////////////////////////////////////////////////////
+BilingualLM::BilingualLM(const std::string &line)
+  :StatefulFeatureFunction(3, line)
+{
+  ReadParameters();
+}
+
+void BilingualLM::EvaluateInIsolation(const Phrase &source
+                                  , const TargetPhrase &targetPhrase
+                                  , ScoreComponentCollection &scoreBreakdown
+                                  , ScoreComponentCollection &estimatedFutureScore) const
+{}
+
+void BilingualLM::EvaluateWithSourceContext(const InputType &input
+                                  , const InputPath &inputPath
+                                  , const TargetPhrase &targetPhrase
+                                  , const StackVec *stackVec
+                                  , ScoreComponentCollection &scoreBreakdown
+                                  , ScoreComponentCollection *estimatedFutureScore) const
+{}
+
+FFState* BilingualLM::EvaluateWhenApplied(
+  const Hypothesis& cur_hypo,
+  const FFState* prev_state,
+  ScoreComponentCollection* accumulator) const
+{
+  // dense scores
+  vector<float> newScores(m_numScoreComponents);
+  newScores[0] = 1.5;
+  newScores[1] = 0.3;
+  newScores[2] = 0.4;
+  accumulator->PlusEquals(this, newScores);
+
+  // int targetLen = cur_hypo.GetCurrTargetPhrase().GetSize(); // ??? [UG]
+  return new BilingualLMState(0);
+}
+
+FFState* BilingualLM::EvaluateWhenApplied(
+  const ChartHypothesis& /* cur_hypo */,
+  int /* featureID - used to index the state in the previous hypotheses */,
+  ScoreComponentCollection* accumulator) const
+{
+  return new BilingualLMState(0);
+}
+
+void BilingualLM::SetParameter(const std::string& key, const std::string& value)
+{
+  if (key == "arg") {
+    // set value here
+  } else {
+    StatefulFeatureFunction::SetParameter(key, value);
+  }
+}
+
+}
+

moses/FF/bilingual-lm/BilingualLM.h

@@ -0,0 +1,58 @@
+#pragma once
+
+#include <string>
+#include "moses/FF/StatefulFeatureFunction.h"
+#include "moses/FF/FFState.h"
+
+namespace Moses
+{
+
+class BilingualLMState : public FFState
+{
+  int m_targetLen;
+public:
+  BilingualLMState(int targetLen)
+    :m_targetLen(targetLen)
+  {}
+
+  int Compare(const FFState& other) const;
+};
+
+class BilingualLM : public StatefulFeatureFunction
+{
+public:
+  BilingualLM(const std::string &line);
+
+  bool IsUseable(const FactorMask &mask) const {
+    return true;
+  }
+  virtual const FFState* EmptyHypothesisState(const InputType &input) const {
+    return new BilingualLMState(0);
+  }
+
+  void EvaluateInIsolation(const Phrase &source
+                , const TargetPhrase &targetPhrase
+                , ScoreComponentCollection &scoreBreakdown
+                , ScoreComponentCollection &estimatedFutureScore) const;
+  void EvaluateWithSourceContext(const InputType &input
+                , const InputPath &inputPath
+                , const TargetPhrase &targetPhrase
+                , const StackVec *stackVec
+                , ScoreComponentCollection &scoreBreakdown
+                , ScoreComponentCollection *estimatedFutureScore = NULL) const;
+  FFState* EvaluateWhenApplied(
+    const Hypothesis& cur_hypo,
+    const FFState* prev_state,
+    ScoreComponentCollection* accumulator) const;
+  FFState* EvaluateWhenApplied(
+    const ChartHypothesis& /* cur_hypo */,
+    int /* featureID - used to index the state in the previous hypotheses */,
+    ScoreComponentCollection* accumulator) const;
+
+  void SetParameter(const std::string& key, const std::string& value);
+
+};
+
+
+}
+