Merge remote-tracking branch 'upstream/master'

20 files changed, 6085 insertions, 1016 deletions

diff --git a/decoder/ff_ngrams.cc b/decoder/ff_ngrams.cc
index d6d79f5e..9c13fdbb 100644
--- a/decoder/ff_ngrams.cc
+++ b/decoder/ff_ngrams.cc
@@ -48,6 +48,9 @@ struct State {
 
 namespace {
   string Escape(const string& x) {
+    if (x.find('=') == string::npos && x.find(';') == string::npos) {
+      return x;
+    }
     string y = x;
     for (int i = 0; i < y.size(); ++i) {
       if (y[i] == '=') y[i]='_';
@@ -57,10 +60,17 @@ namespace {
   }
 }
 
-static bool ParseArgs(string const& in, bool* explicit_markers, unsigned* order) {
+static bool ParseArgs(string const& in, bool* explicit_markers, unsigned* order, vector<string>& prefixes, string& target_separator) {
   vector<string> const& argv=SplitOnWhitespace(in);
   *explicit_markers = false;
   *order = 3;
+  prefixes.push_back("NOT-USED");
+  prefixes.push_back("U:"); // default unigram prefix
+  prefixes.push_back("B:"); // default bigram prefix
+  prefixes.push_back("T:"); // ...etc
+  prefixes.push_back("4:"); // ...etc
+  prefixes.push_back("5:"); // max allowed!
+  target_separator = "_";
 #define LMSPEC_NEXTARG if (i==argv.end()) {            \
     cerr << "Missing argument for "<<*last<<". "; goto usage; \
     } else { ++i; }
@@ -73,6 +83,30 @@ static bool ParseArgs(string const& in, bool* explicit_markers, unsigned* order)
       case 'x':
         *explicit_markers = true;
         break;
+      case 'U':
+	LMSPEC_NEXTARG;
+	prefixes[1] = *i;
+	break;
+      case 'B':
+	LMSPEC_NEXTARG;
+	prefixes[2] = *i;
+	break;
+      case 'T':
+	LMSPEC_NEXTARG;
+	prefixes[3] = *i;
+	break;
+      case '4':
+	LMSPEC_NEXTARG;
+	prefixes[4] = *i;
+	break;
+      case '5':
+	LMSPEC_NEXTARG;
+	prefixes[5] = *i;
+	break;
+      case 'S':
+	LMSPEC_NEXTARG;
+	target_separator = *i;
+	break;
       case 'o':
         LMSPEC_NEXTARG; *order=atoi((*i).c_str());
         break;
@@ -86,7 +120,29 @@ static bool ParseArgs(string const& in, bool* explicit_markers, unsigned* order)
   }
   return true;
 usage:
-  cerr << "NgramFeatures is incorrect!\n";
+  cerr << "Wrong parameters for NgramFeatures.\n\n"
+
+       << "NgramFeatures Usage: \n"			     
+       << " feature_function=NgramFeatures filename.lm [-x] [-o <order>] \n"
+       << " [-U <unigram-prefix>] [-B <bigram-prefix>][-T <trigram-prefix>]\n"
+       << " [-4 <4-gram-prefix>] [-5 <5-gram-prefix>] [-S <separator>]\n\n" 
+    
+       << "Defaults: \n"
+       << "  <order>          = 3\n" 
+       << "  <unigram-prefix> = U:\n"
+       << "  <bigram-prefix>  = B:\n"
+       << "  <trigram-prefix> = T:\n"
+       << "  <4-gram-prefix>  = 4:\n"
+       << "  <5-gram-prefix>  = 5:\n"
+       << "  <separator>      = _\n"
+       << "  -x (i.e. explicit sos/eos markers) is turned off\n\n"
+
+       << "Example configuration: \n"
+       << "  feature_function=NgramFeatures -o 3 -T tri: -S |\n\n"
+
+       << "Example feature instantiation: \n"
+       << "  tri:a|b|c \n\n";
+
   return false;
 }
 
@@ -158,16 +214,12 @@ class NgramDetectorImpl {
       int& fid = ft->fids[curword];
       ++n;
       if (!fid) {
-        const char* code="_UBT456789"; // prefix code (unigram, bigram, etc.)
         ostringstream os;
-        os << code[n] << ':';
+        os << prefixes_[n];
         for (int i = n-1; i >= 0; --i) {
-          os << (i != n-1 ? "_" : "");
+          os << (i != n-1 ? target_separator_ : "");
           const string& tok = TD::Convert(buf[i]);
-          if (tok.find('=') == string::npos)
-            os << tok;
-          else
-            os << Escape(tok);
+	  os << Escape(tok);
         }
         fid = FD::Convert(os.str());
       }
@@ -297,7 +349,8 @@ class NgramDetectorImpl {
   }
 
  public:
-  explicit NgramDetectorImpl(bool explicit_markers, unsigned order) :
+  explicit NgramDetectorImpl(bool explicit_markers, unsigned order,
+			     vector<string>& prefixes, string& target_separator) :
       kCDEC_UNK(TD::Convert("<unk>")) ,
       add_sos_eos_(!explicit_markers) {
     order_ = order;
@@ -305,6 +358,8 @@ class NgramDetectorImpl {
     unscored_size_offset_ = (order_ - 1) * sizeof(WordID);
     is_complete_offset_ = unscored_size_offset_ + 1;
     unscored_words_offset_ = is_complete_offset_ + 1;
+    prefixes_ = prefixes;
+    target_separator_ = target_separator;
 
     // special handling of beginning / ending sentence markers
     dummy_state_ = new char[state_size_];
@@ -340,6 +395,8 @@ class NgramDetectorImpl {
   char* dummy_state_;
   vector<const void*> dummy_ants_;
   TRulePtr dummy_rule_;
+  vector<string> prefixes_;
+  string target_separator_;
   struct FidTree {
     map<WordID, int> fids;
     map<WordID, FidTree> levels;
@@ -348,11 +405,13 @@ class NgramDetectorImpl {
 };
 
 NgramDetector::NgramDetector(const string& param) {
-  string filename, mapfile, featname;
+  string filename, mapfile, featname, target_separator;
+  vector<string> prefixes;
   bool explicit_markers = false;
   unsigned order = 3;
-  ParseArgs(param, &explicit_markers, &order);
-  pimpl_ = new NgramDetectorImpl(explicit_markers, order);
+  ParseArgs(param, &explicit_markers, &order, prefixes, target_separator);
+  pimpl_ = new NgramDetectorImpl(explicit_markers, order, prefixes, 
+				 target_separator);
   SetStateSize(pimpl_->ReserveStateSize());
 }
 
diff --git a/decoder/ff_ngrams.h b/decoder/ff_ngrams.h
index 82f61b33..064dbb49 100644
--- a/decoder/ff_ngrams.h
+++ b/decoder/ff_ngrams.h
@@ -10,7 +10,7 @@
 struct NgramDetectorImpl;
 class NgramDetector : public FeatureFunction {
  public:
-  // param = "filename.lm [-o n]"
+  // param = "filename.lm [-o <order>] [-U <unigram-prefix>] [-B <bigram-prefix>] [-T <trigram-prefix>] [-4 <4-gram-prefix>] [-5 <5-gram-prefix>] [-S <separator>]
   NgramDetector(const std::string& param);
   ~NgramDetector();
   virtual void FinalTraversalFeatures(const void* context,
diff --git a/minrisk/minrisk_optimize.cc b/minrisk/minrisk_optimize.cc
index 6e651994..da8b5260 100644
--- a/minrisk/minrisk_optimize.cc
+++ b/minrisk/minrisk_optimize.cc
@@ -17,6 +17,7 @@
 #include "ns_docscorer.h"
 #include "candidate_set.h"
 #include "risk.h"
+#include "entropy.h"
 
 using namespace std;
 namespace po = boost::program_options;
@@ -28,6 +29,9 @@ void InitCommandLine(int argc, char** argv, po::variables_map* conf) {
         ("weights,w",po::value<string>(), "[REQD] Weights files from current iterations")
         ("input,i",po::value<string>()->default_value("-"), "Input file to map (- is STDIN)")
         ("evaluation_metric,m",po::value<string>()->default_value("IBM_BLEU"), "Evaluation metric (ibm_bleu, koehn_bleu, nist_bleu, ter, meteor, etc.)")
+        ("temperature,T",po::value<double>()->default_value(0.0), "Temperature parameter for objective (>0 increases the entropy)")
+        ("l1_strength,C",po::value<double>()->default_value(0.0), "L1 regularization strength")
+        ("memory_buffers,M",po::value<unsigned>()->default_value(20), "Memory buffers used in LBFGS")
         ("kbest_repository,R",po::value<string>(), "Accumulate k-best lists from previous iterations (parameter is path to repository)")
         ("kbest_size,k",po::value<unsigned>()->default_value(500u), "Top k-hypotheses to extract")
         ("help,h", "Help");
@@ -52,36 +56,80 @@ void InitCommandLine(int argc, char** argv, po::variables_map* conf) {
 EvaluationMetric* metric = NULL;
 
 struct RiskObjective {
-  explicit RiskObjective(const vector<training::CandidateSet>& tr) : training(tr) {}
+  explicit RiskObjective(const vector<training::CandidateSet>& tr, const double temp) : training(tr), T(temp) {}
   double operator()(const vector<double>& x, double* g) const {
     fill(g, g + x.size(), 0.0);
     double obj = 0;
+    double h = 0;
     for (unsigned i = 0; i < training.size(); ++i) {
       training::CandidateSetRisk risk(training[i], *metric);
-      SparseVector<double> tg;
+      training::CandidateSetEntropy entropy(training[i]);
+      SparseVector<double> tg, hg;
       double r = risk(x, &tg);
+      double hh = entropy(x, &hg);
+      h += hh;
       obj += r;
       for (SparseVector<double>::iterator it = tg.begin(); it != tg.end(); ++it)
         g[it->first] += it->second;
+      if (T) {
+        for (SparseVector<double>::iterator it = hg.begin(); it != hg.end(); ++it)
+          g[it->first] += T * it->second;
+      }
     }
-    cerr << (1-(obj / training.size())) << endl;
-    return obj;
+    cerr << (1-(obj / training.size())) << "  H=" << h << endl;
+    return obj - T * h;
   }
   const vector<training::CandidateSet>& training;
+  const double T; // temperature for entropy regularization
 };  
 
 double LearnParameters(const vector<training::CandidateSet>& training,
+                       const double temp, // > 0 increases the entropy, < 0 decreases the entropy
                        const double C1,
                        const unsigned memory_buffers,
                        vector<weight_t>* px) {
-  RiskObjective obj(training);
+  RiskObjective obj(training, temp);
   LBFGS<RiskObjective> lbfgs(px, obj, memory_buffers, C1);
   lbfgs.MinimizeFunction();
   return 0;
 }
 
-// runs lines 4--15 of rampion algorithm
+#if 0
+struct FooLoss {
+  double operator()(const vector<double>& x, double* g) const {
+    fill(g, g + x.size(), 0.0);
+    training::CandidateSet cs;
+    training::CandidateSetEntropy cse(cs);
+    cs.cs.resize(3);
+    cs.cs[0].fmap.set_value(FD::Convert("F1"), -1.0);
+    cs.cs[1].fmap.set_value(FD::Convert("F2"), 1.0);
+    cs.cs[2].fmap.set_value(FD::Convert("F1"), 2.0);
+    cs.cs[2].fmap.set_value(FD::Convert("F2"), 0.5);
+    SparseVector<double> xx;
+    double h = cse(x, &xx);
+    cerr << cse(x, &xx) << endl; cerr << "G: " << xx << endl;
+    for (SparseVector<double>::iterator i = xx.begin(); i != xx.end(); ++i)
+      g[i->first] += i->second;
+    return -h;
+  }
+};
+#endif
+
 int main(int argc, char** argv) {
+#if 0
+  training::CandidateSet cs;
+  training::CandidateSetEntropy cse(cs);
+  cs.cs.resize(3);
+  cs.cs[0].fmap.set_value(FD::Convert("F1"), -1.0);
+  cs.cs[1].fmap.set_value(FD::Convert("F2"), 1.0);
+  cs.cs[2].fmap.set_value(FD::Convert("F1"), 2.0);
+  cs.cs[2].fmap.set_value(FD::Convert("F2"), 0.5);
+  FooLoss foo;
+  vector<double> ww(FD::NumFeats()); ww[FD::Convert("F1")] = 1.0;
+  LBFGS<FooLoss> lbfgs(&ww, foo, 100, 0.0);
+  lbfgs.MinimizeFunction();
+  return 1;
+#endif
   po::variables_map conf;
   InitCommandLine(argc, argv, &conf);
   const string evaluation_metric = conf["evaluation_metric"].as<string>();
@@ -89,8 +137,6 @@ int main(int argc, char** argv) {
   metric = EvaluationMetric::Instance(evaluation_metric);
   DocumentScorer ds(metric, conf["reference"].as<vector<string> >());
   cerr << "Loaded " << ds.size() << " references for scoring with " << evaluation_metric << endl;
-  double goodsign = -1;
-  double badsign = -goodsign;
 
   Hypergraph hg;
   string last_file;
@@ -141,7 +187,10 @@ int main(int argc, char** argv) {
   cerr << "\nHypergraphs loaded.\n";
   weights.resize(FD::NumFeats());
 
-  LearnParameters(kis, 0.0, 100, &weights);
+  double c1 = conf["l1_strength"].as<double>();
+  double temp = conf["temperature"].as<double>();
+  unsigned m = conf["memory_buffers"].as<unsigned>();
+  LearnParameters(kis, temp, c1, m, &weights);
   Weights::WriteToFile("-", weights);
   return 0;
 }
diff --git a/python/cdec/__init__.py b/python/cdec/__init__.py
index eda81194..0d7b8782 100644
--- a/python/cdec/__init__.py
+++ b/python/cdec/__init__.py
@@ -1 +1,2 @@
 from _cdec import Decoder, Lattice
+import score
diff --git a/python/cdec/score.py b/python/cdec/score.py
new file mode 100644
index 00000000..c107446f
--- /dev/null
+++ b/python/cdec/score.py
@@ -0,0 +1 @@
+from _cdec import BLEU, TER
diff --git a/python/setup.py b/python/setup.py
index 49a1ec8f..cc8b289d 100644
--- a/python/setup.py
+++ b/python/setup.py
@@ -3,8 +3,8 @@ from distutils.extension import Extension
 from Cython.Distutils import build_ext
 import os
 
-INC = ['..', 'src/', '../decoder', '../utils']
-LIB = ['../decoder', '../utils', '../mteval', '../klm/lm', '../klm/util']
+INC = ['..', 'src/', '../decoder', '../utils', '../mteval']
+LIB = ['../decoder', '../utils', '../mteval', '../training', '../klm/lm', '../klm/util']
 
 BOOST_ROOT = os.getenv('BOOST_ROOT')
 if BOOST_ROOT:
@@ -18,7 +18,8 @@ ext_modules = [
         include_dirs=INC,
         library_dirs=LIB,
         libraries=['boost_program_options-mt', 'z',
-                   'cdec', 'utils', 'mteval', 'klm', 'klm_util'])
+                   'cdec', 'utils', 'mteval', 'training', 'klm', 'klm_util'],
+        extra_compile_args=['-DHAVE_CONFIG_H']),
 ]
 
 setup(
diff --git a/python/src/_cdec.cpp b/python/src/_cdec.cpp
index 0b9b9911..bc522b32 100644
--- a/python/src/_cdec.cpp
+++ b/python/src/_cdec.cpp
@@ -1,4 +1,4 @@
-/* Generated by Cython 0.16 on Sat Jun 23 11:57:21 2012 */
+/* Generated by Cython 0.16 on Mon Jul  2 17:01:11 2012 */
 
 #define PY_SSIZE_T_CLEAN
 #include "Python.h"
@@ -279,11 +279,12 @@
 #include "utils/wordid.h"
 #include "utils/small_vector.h"
 #include "utils/sparse_vector.h"
-#include "utils/tdict.cc"
+#include "utils/tdict.h"
 #include "utils/verbose.h"
 #include "utils/fdict.h"
 #include "utils/filelib.h"
 #include "utils/sampler.h"
+#include <boost/shared_ptr.hpp>
 #include "decoder/lattice.h"
 #include "decoder/hg.h"
 #include "decoder/viterbi.h"
@@ -295,6 +296,8 @@
 #include "decoder/decoder.h"
 #include "observer.h"
 #include "decoder/kbest.h"
+#include "mteval/ns.h"
+#include "training/candidate_set.h"
 #ifdef _OPENMP
 #include <omp.h>
 #endif /* _OPENMP */
@@ -381,50 +384,94 @@ static const char *__pyx_f[] = {
   "vectors.pxi",
   "hypergraph.pxi",
   "lattice.pxi",
+  "mteval.pxi",
 };
 
 /*--- Type declarations ---*/
-struct __pyx_obj_5_cdec___pyx_scope_struct_4_sample;
+struct __pyx_obj_5_cdec_Scorer;
+struct __pyx_obj_5_cdec_CandidateSet;
+struct __pyx_obj_5_cdec_SufficientStats;
 struct __pyx_obj_5_cdec___pyx_scope_struct_1___iter__;
+struct __pyx_obj_5_cdec___pyx_scope_struct_4_kbest_features;
 struct __pyx_obj_5_cdec___pyx_scope_struct_3_kbest_tree;
 struct __pyx_obj_5_cdec_Decoder;
+struct __pyx_obj_5_cdec_SegmentEvaluator;
 struct __pyx_obj_5_cdec_SparseVector;
 struct __pyx_obj_5_cdec_Hypergraph;
 struct __pyx_obj_5_cdec_Lattice;
-struct __pyx_obj_5_cdec___pyx_scope_struct_5___iter__;
 struct __pyx_obj_5_cdec___pyx_scope_struct____iter__;
 struct __pyx_obj_5_cdec___pyx_scope_struct_2_kbest;
+struct __pyx_obj_5_cdec_Candidate;
+struct __pyx_obj_5_cdec___pyx_scope_struct_5_sample;
 struct __pyx_obj_5_cdec_DenseVector;
+struct __pyx_obj_5_cdec___pyx_scope_struct_6___iter__;
+struct __pyx_obj_5_cdec___pyx_scope_struct_8___iter__;
+struct __pyx_obj_5_cdec___pyx_scope_struct_7___iter__;
+struct __pyx_opt_args_5_cdec_as_str;
 
-/* "/Users/vchahun/Sandbox/cdec/python/src/hypergraph.pxi":56
- *         del derivations
+/* "/Users/vchahun/Sandbox/cdec/python/src/mteval.pxi":3
+ * cimport mteval
+ * 
+ * cdef char* as_str(sentence, error_msg='Cannot convert type %s to str'):             # <<<<<<<<<<<<<<
+ *     cdef bytes ret
+ *     if isinstance(sentence, unicode):
+ */
+struct __pyx_opt_args_5_cdec_as_str {
+  int __pyx_n;
+  PyObject *error_msg;
+};
+
+/* "/Users/vchahun/Sandbox/cdec/python/src/mteval.pxi":109
+ *         return CandidateSet(self)
+ * 
+ * cdef class Scorer:             # <<<<<<<<<<<<<<
+ *     cdef string* name
  * 
- *     def sample(self, unsigned n):             # <<<<<<<<<<<<<<
- *         cdef vector[hypergraph.Hypothesis]* hypos = new vector[hypergraph.Hypothesis]()
- *         if self.rng == NULL:
  */
-struct __pyx_obj_5_cdec___pyx_scope_struct_4_sample {
+struct __pyx_obj_5_cdec_Scorer {
   PyObject_HEAD
-  std::vector<HypergraphSampler::Hypothesis> *__pyx_v_hypos;
-  unsigned int __pyx_v_k;
-  unsigned int __pyx_v_n;
-  struct __pyx_obj_5_cdec_Hypergraph *__pyx_v_self;
-  PyObject *__pyx_v_sentence;
-  size_t __pyx_t_0;
-  unsigned int __pyx_t_1;
+  std::string *name;
+};
+
+
+/* "/Users/vchahun/Sandbox/cdec/python/src/mteval.pxi":59
+ *         return result
+ * 
+ * cdef class CandidateSet:             # <<<<<<<<<<<<<<
+ *     cdef shared_ptr[mteval.SegmentEvaluator]* scorer
+ *     cdef mteval.EvaluationMetric* metric
+ */
+struct __pyx_obj_5_cdec_CandidateSet {
+  PyObject_HEAD
+  boost::shared_ptr<SegmentEvaluator> *scorer;
+  EvaluationMetric *metric;
+  training::CandidateSet *cs;
+};
+
+
+/* "/Users/vchahun/Sandbox/cdec/python/src/mteval.pxi":27
+ *             return fmap
+ * 
+ * cdef class SufficientStats:             # <<<<<<<<<<<<<<
+ *     cdef mteval.SufficientStats* stats
+ *     cdef mteval.EvaluationMetric* metric
+ */
+struct __pyx_obj_5_cdec_SufficientStats {
+  PyObject_HEAD
+  SufficientStats *stats;
+  EvaluationMetric *metric;
 };
 
 
-/* "/Users/vchahun/Sandbox/cdec/python/src/vectors.pxi":43
+/* "/Users/vchahun/Sandbox/cdec/python/src/vectors.pxi":55
  *         self.vector.set_value(fid, value)
  * 
  *     def __iter__(self):             # <<<<<<<<<<<<<<
  *         cdef FastSparseVector[weight_t].const_iterator* it = new FastSparseVector[weight_t].const_iterator(self.vector[0], False)
- *         cdef str fname
+ *         try:
  */
 struct __pyx_obj_5_cdec___pyx_scope_struct_1___iter__ {
   PyObject_HEAD
-  PyObject *__pyx_v_fname;
   size_t __pyx_v_i;
   FastSparseVector<weight_t>::const_iterator *__pyx_v_it;
   struct __pyx_obj_5_cdec_SparseVector *__pyx_v_self;
@@ -433,8 +480,28 @@ struct __pyx_obj_5_cdec___pyx_scope_struct_1___iter__ {
 };
 
 
-/* "/Users/vchahun/Sandbox/cdec/python/src/hypergraph.pxi":44
- *         del derivations
+/* "/Users/vchahun/Sandbox/cdec/python/src/hypergraph.pxi":60
+ *             del derivations
+ * 
+ *     def kbest_features(self, size):             # <<<<<<<<<<<<<<
+ *         cdef kb.KBestDerivations[FastSparseVector[weight_t], kb.FeatureVectorTraversal]* derivations = new kb.KBestDerivations[FastSparseVector[weight_t], kb.FeatureVectorTraversal](self.hg[0], size)
+ *         cdef kb.KBestDerivations[FastSparseVector[weight_t], kb.FeatureVectorTraversal].Derivation* derivation
+ */
+struct __pyx_obj_5_cdec___pyx_scope_struct_4_kbest_features {
+  PyObject_HEAD
+  KBest::KBestDerivations<FastSparseVector<weight_t>,FeatureVectorTraversal>::Derivation *__pyx_v_derivation;
+  KBest::KBestDerivations<FastSparseVector<weight_t>,FeatureVectorTraversal> *__pyx_v_derivations;
+  struct __pyx_obj_5_cdec_SparseVector *__pyx_v_fmap;
+  unsigned int __pyx_v_k;
+  struct __pyx_obj_5_cdec_Hypergraph *__pyx_v_self;
+  PyObject *__pyx_v_size;
+  unsigned int __pyx_t_0;
+  long __pyx_t_1;
+};
+
+
+/* "/Users/vchahun/Sandbox/cdec/python/src/hypergraph.pxi":46
+ *             del derivations
  * 
  *     def kbest_tree(self, size):             # <<<<<<<<<<<<<<
  *         cdef kb.KBestDerivations[vector[WordID], kb.ETreeTraversal]* derivations = new kb.KBestDerivations[vector[WordID], kb.ETreeTraversal](self.hg[0], size)
@@ -454,7 +521,7 @@ struct __pyx_obj_5_cdec___pyx_scope_struct_3_kbest_tree {
 
 
 /* "_cdec.pyx":15
- *     pass
+ * class ParseFailed(Exception): pass
  * 
  * cdef class Decoder:             # <<<<<<<<<<<<<<
  *     cdef decoder.Decoder* dec
@@ -467,7 +534,21 @@ struct __pyx_obj_5_cdec_Decoder {
 };
 
 
-/* "/Users/vchahun/Sandbox/cdec/python/src/vectors.pxi":32
+/* "/Users/vchahun/Sandbox/cdec/python/src/mteval.pxi":90
+ *         self.cs.AddKBestCandidates(hypergraph.hg[0], k, self.scorer.get())
+ * 
+ * cdef class SegmentEvaluator:             # <<<<<<<<<<<<<<
+ *     cdef shared_ptr[mteval.SegmentEvaluator]* scorer
+ *     cdef mteval.EvaluationMetric* metric
+ */
+struct __pyx_obj_5_cdec_SegmentEvaluator {
+  PyObject_HEAD
+  boost::shared_ptr<SegmentEvaluator> *scorer;
+  EvaluationMetric *metric;
+};
+
+
+/* "/Users/vchahun/Sandbox/cdec/python/src/vectors.pxi":36
  *         return sparse
  * 
  * cdef class SparseVector:             # <<<<<<<<<<<<<<
@@ -507,23 +588,7 @@ struct __pyx_obj_5_cdec_Lattice {
 };
 
 
-/* "/Users/vchahun/Sandbox/cdec/python/src/lattice.pxi":50
- *         return hypergraph.AsPLF(self.lattice[0], True).c_str()
- * 
- *     def __iter__(self):             # <<<<<<<<<<<<<<
- *         cdef unsigned i
- *         for i in range(len(self)):
- */
-struct __pyx_obj_5_cdec___pyx_scope_struct_5___iter__ {
-  PyObject_HEAD
-  unsigned int __pyx_v_i;
-  struct __pyx_obj_5_cdec_Lattice *__pyx_v_self;
-  Py_ssize_t __pyx_t_0;
-  unsigned int __pyx_t_1;
-};
-
-
-/* "/Users/vchahun/Sandbox/cdec/python/src/vectors.pxi":18
+/* "/Users/vchahun/Sandbox/cdec/python/src/vectors.pxi":22
  *         self.vector[0][fid] = value
  * 
  *     def __iter__(self):             # <<<<<<<<<<<<<<
@@ -559,11 +624,44 @@ struct __pyx_obj_5_cdec___pyx_scope_struct_2_kbest {
 };
 
 
+/* "/Users/vchahun/Sandbox/cdec/python/src/mteval.pxi":13
+ *     return ret
+ * 
+ * cdef class Candidate:             # <<<<<<<<<<<<<<
+ *     cdef mteval.Candidate* candidate
+ *     cdef public float score
+ */
+struct __pyx_obj_5_cdec_Candidate {
+  PyObject_HEAD
+  const training::Candidate *candidate;
+  float score;
+};
+
+
+/* "/Users/vchahun/Sandbox/cdec/python/src/hypergraph.pxi":75
+ *             del derivations
+ * 
+ *     def sample(self, unsigned n):             # <<<<<<<<<<<<<<
+ *         cdef vector[hypergraph.Hypothesis]* hypos = new vector[hypergraph.Hypothesis]()
+ *         if self.rng == NULL:
+ */
+struct __pyx_obj_5_cdec___pyx_scope_struct_5_sample {
+  PyObject_HEAD
+  std::vector<HypergraphSampler::Hypothesis> *__pyx_v_hypos;
+  unsigned int __pyx_v_k;
+  unsigned int __pyx_v_n;
+  struct __pyx_obj_5_cdec_Hypergraph *__pyx_v_self;
+  PyObject *__pyx_v_sentence;
+  size_t __pyx_t_0;
+  unsigned int __pyx_t_1;
+};
+
+
 /* "/Users/vchahun/Sandbox/cdec/python/src/vectors.pxi":3
  * from cython.operator cimport preincrement as pinc
  * 
  * cdef class DenseVector:             # <<<<<<<<<<<<<<
- *     cdef vector[weight_t]* vector
+ *     cdef vector[weight_t]* vector # Not owned by DenseVector
  * 
  */
 struct __pyx_obj_5_cdec_DenseVector {
@@ -571,6 +669,55 @@ struct __pyx_obj_5_cdec_DenseVector {
   std::vector<weight_t> *vector;
 };
 
+
+/* "/Users/vchahun/Sandbox/cdec/python/src/lattice.pxi":50
+ *         return hypergraph.AsPLF(self.lattice[0], True).c_str()
+ * 
+ *     def __iter__(self):             # <<<<<<<<<<<<<<
+ *         cdef unsigned i
+ *         for i in range(len(self)):
+ */
+struct __pyx_obj_5_cdec___pyx_scope_struct_6___iter__ {
+  PyObject_HEAD
+  unsigned int __pyx_v_i;
+  struct __pyx_obj_5_cdec_Lattice *__pyx_v_self;
+  Py_ssize_t __pyx_t_0;
+  unsigned int __pyx_t_1;
+};
+
+
+/* "/Users/vchahun/Sandbox/cdec/python/src/mteval.pxi":82
+ *         return candidate
+ * 
+ *     def __iter__(self):             # <<<<<<<<<<<<<<
+ *         cdef unsigned i
+ *         for i in range(len(self)):
+ */
+struct __pyx_obj_5_cdec___pyx_scope_struct_8___iter__ {
+  PyObject_HEAD
+  unsigned int __pyx_v_i;
+  struct __pyx_obj_5_cdec_CandidateSet *__pyx_v_self;
+  Py_ssize_t __pyx_t_0;
+  unsigned int __pyx_t_1;
+};
+
+
+/* "/Users/vchahun/Sandbox/cdec/python/src/mteval.pxi":45
+ *         return self.stats.size()
+ * 
+ *     def __iter__(self):             # <<<<<<<<<<<<<<
+ *         for i in range(len(self)):
+ *             yield self.stats[0][i]
+ */
+struct __pyx_obj_5_cdec___pyx_scope_struct_7___iter__ {
+  PyObject_HEAD
+  PyObject *__pyx_v_i;
+  struct __pyx_obj_5_cdec_SufficientStats *__pyx_v_self;
+  Py_ssize_t __pyx_t_0;
+  PyObject *__pyx_t_1;
+  PyObject *(*__pyx_t_2)(PyObject *);
+};
+
 #ifndef CYTHON_REFNANNY
   #define CYTHON_REFNANNY 0
 #endif
@@ -635,6 +782,8 @@ static void __Pyx_Raise(PyObject *type, PyObject *value, PyObject *tb, PyObject
 static int __Pyx_ArgTypeTest(PyObject *obj, PyTypeObject *type, int none_allowed,
     const char *name, int exact); /*proto*/
 
+static CYTHON_INLINE int __Pyx_TypeTest(PyObject *obj, PyTypeObject *type); /*proto*/
+
 static void __Pyx_RaiseDoubleKeywordsError(const char* func_name, PyObject* kw_name); /*proto*/
 
 static int __Pyx_ParseOptionalKeywords(PyObject *kwds, PyObject **argnames[], \
@@ -736,8 +885,6 @@ static double __Pyx__PyObject_AsDouble(PyObject* obj); /* proto */
 
 static int __Pyx_GetException(PyObject **type, PyObject **value, PyObject **tb); /*proto*/
 
-static CYTHON_INLINE int __Pyx_TypeTest(PyObject *obj, PyTypeObject *type); /*proto*/
-
 static CYTHON_INLINE void __Pyx_ExceptionSave(PyObject **type, PyObject **value, PyObject **tb); /*proto*/
 static void __Pyx_ExceptionReset(PyObject *type, PyObject *value, PyObject *tb); /*proto*/
 
@@ -801,6 +948,9 @@ static __pyx_GeneratorObject *__Pyx_Generator_New(__pyx_generator_body_t body,
                                                   PyObject *closure);
 static int __pyx_Generator_init(void);
 
+static void __Pyx_WriteUnraisable(const char *name, int clineno,
+                                  int lineno, const char *filename); /*proto*/
+
 static int __Pyx_check_binary_version(void);
 
 typedef struct {
@@ -841,18 +991,29 @@ static int __Pyx_InitStrings(__Pyx_StringTabEntry *t); /*proto*/
 
 /* Module declarations from 'kbest' */
 
+/* Module declarations from 'mteval' */
+
 /* Module declarations from '_cdec' */
 static PyTypeObject *__pyx_ptype_5_cdec_DenseVector = 0;
 static PyTypeObject *__pyx_ptype_5_cdec_SparseVector = 0;
 static PyTypeObject *__pyx_ptype_5_cdec_Hypergraph = 0;
 static PyTypeObject *__pyx_ptype_5_cdec_Lattice = 0;
+static PyTypeObject *__pyx_ptype_5_cdec_Candidate = 0;
+static PyTypeObject *__pyx_ptype_5_cdec_SufficientStats = 0;
+static PyTypeObject *__pyx_ptype_5_cdec_CandidateSet = 0;
+static PyTypeObject *__pyx_ptype_5_cdec_SegmentEvaluator = 0;
+static PyTypeObject *__pyx_ptype_5_cdec_Scorer = 0;
 static PyTypeObject *__pyx_ptype_5_cdec_Decoder = 0;
 static PyTypeObject *__pyx_ptype_5_cdec___pyx_scope_struct____iter__ = 0;
 static PyTypeObject *__pyx_ptype_5_cdec___pyx_scope_struct_1___iter__ = 0;
 static PyTypeObject *__pyx_ptype_5_cdec___pyx_scope_struct_2_kbest = 0;
 static PyTypeObject *__pyx_ptype_5_cdec___pyx_scope_struct_3_kbest_tree = 0;
-static PyTypeObject *__pyx_ptype_5_cdec___pyx_scope_struct_4_sample = 0;
-static PyTypeObject *__pyx_ptype_5_cdec___pyx_scope_struct_5___iter__ = 0;
+static PyTypeObject *__pyx_ptype_5_cdec___pyx_scope_struct_4_kbest_features = 0;
+static PyTypeObject *__pyx_ptype_5_cdec___pyx_scope_struct_5_sample = 0;
+static PyTypeObject *__pyx_ptype_5_cdec___pyx_scope_struct_6___iter__ = 0;
+static PyTypeObject *__pyx_ptype_5_cdec___pyx_scope_struct_7___iter__ = 0;
+static PyTypeObject *__pyx_ptype_5_cdec___pyx_scope_struct_8___iter__ = 0;
+static char *__pyx_f_5_cdec_as_str(PyObject *, struct __pyx_opt_args_5_cdec_as_str *__pyx_optional_args); /*proto*/
 #define __Pyx_MODULE_NAME "_cdec"
 int __pyx_module_is_main__cdec = 0;
 
@@ -860,34 +1021,39 @@ int __pyx_module_is_main__cdec = 0;
 static PyObject *__pyx_builtin_Exception;
 static PyObject *__pyx_builtin_KeyError;
 static PyObject *__pyx_builtin_range;
-static PyObject *__pyx_builtin_ValueError;
+static PyObject *__pyx_builtin_TypeError;
 static PyObject *__pyx_builtin_NotImplemented;
 static PyObject *__pyx_builtin_eval;
 static PyObject *__pyx_builtin_enumerate;
-static PyObject *__pyx_builtin_TypeError;
 static PyObject *__pyx_builtin_IndexError;
 static PyObject *__pyx_builtin_open;
-static PyObject *__pyx_pf_5_cdec_11DenseVector___getitem__(struct __pyx_obj_5_cdec_DenseVector *__pyx_v_self, char *__pyx_v_fname); /* proto */
-static int __pyx_pf_5_cdec_11DenseVector_2__setitem__(struct __pyx_obj_5_cdec_DenseVector *__pyx_v_self, char *__pyx_v_fname, float __pyx_v_value); /* proto */
-static PyObject *__pyx_pf_5_cdec_11DenseVector_4__iter__(struct __pyx_obj_5_cdec_DenseVector *__pyx_v_self); /* proto */
-static PyObject *__pyx_pf_5_cdec_11DenseVector_7dot(struct __pyx_obj_5_cdec_DenseVector *__pyx_v_self, struct __pyx_obj_5_cdec_SparseVector *__pyx_v_other); /* proto */
-static PyObject *__pyx_pf_5_cdec_11DenseVector_9tosparse(struct __pyx_obj_5_cdec_DenseVector *__pyx_v_self); /* proto */
-static PyObject *__pyx_pf_5_cdec_12SparseVector___getitem__(struct __pyx_obj_5_cdec_SparseVector *__pyx_v_self, char *__pyx_v_fname); /* proto */
-static int __pyx_pf_5_cdec_12SparseVector_2__setitem__(struct __pyx_obj_5_cdec_SparseVector *__pyx_v_self, char *__pyx_v_fname, float __pyx_v_value); /* proto */
-static PyObject *__pyx_pf_5_cdec_12SparseVector_4__iter__(struct __pyx_obj_5_cdec_SparseVector *__pyx_v_self); /* proto */
-static PyObject *__pyx_pf_5_cdec_12SparseVector_7dot(struct __pyx_obj_5_cdec_SparseVector *__pyx_v_self, PyObject *__pyx_v_other); /* proto */
-static PyObject *__pyx_pf_5_cdec_12SparseVector_9todense(struct __pyx_obj_5_cdec_SparseVector *__pyx_v_self); /* proto */
-static PyObject *__pyx_pf_5_cdec_12SparseVector_11__richcmp__(struct __pyx_obj_5_cdec_SparseVector *__pyx_v_self, struct __pyx_obj_5_cdec_SparseVector *__pyx_v_other, int __pyx_v_op); /* proto */
-static Py_ssize_t __pyx_pf_5_cdec_12SparseVector_13__len__(struct __pyx_obj_5_cdec_SparseVector *__pyx_v_self); /* proto */
-static int __pyx_pf_5_cdec_12SparseVector_15__contains__(struct __pyx_obj_5_cdec_SparseVector *__pyx_v_self, char *__pyx_v_fname); /* proto */
-static PyObject *__pyx_pf_5_cdec_12SparseVector_17__iadd__(struct __pyx_obj_5_cdec_SparseVector *__pyx_v_self, struct __pyx_obj_5_cdec_SparseVector *__pyx_v_other); /* proto */
-static PyObject *__pyx_pf_5_cdec_12SparseVector_19__isub__(struct __pyx_obj_5_cdec_SparseVector *__pyx_v_self, struct __pyx_obj_5_cdec_SparseVector *__pyx_v_other); /* proto */
-static PyObject *__pyx_pf_5_cdec_12SparseVector_21__imul__(struct __pyx_obj_5_cdec_SparseVector *__pyx_v_self, float __pyx_v_scalar); /* proto */
+static Py_ssize_t __pyx_pf_5_cdec_11DenseVector___len__(struct __pyx_obj_5_cdec_DenseVector *__pyx_v_self); /* proto */
+static PyObject *__pyx_pf_5_cdec_11DenseVector_2__getitem__(struct __pyx_obj_5_cdec_DenseVector *__pyx_v_self, char *__pyx_v_fname); /* proto */
+static int __pyx_pf_5_cdec_11DenseVector_4__setitem__(struct __pyx_obj_5_cdec_DenseVector *__pyx_v_self, char *__pyx_v_fname, float __pyx_v_value); /* proto */
+static PyObject *__pyx_pf_5_cdec_11DenseVector_6__iter__(struct __pyx_obj_5_cdec_DenseVector *__pyx_v_self); /* proto */
+static PyObject *__pyx_pf_5_cdec_11DenseVector_9dot(struct __pyx_obj_5_cdec_DenseVector *__pyx_v_self, struct __pyx_obj_5_cdec_SparseVector *__pyx_v_other); /* proto */
+static PyObject *__pyx_pf_5_cdec_11DenseVector_11tosparse(struct __pyx_obj_5_cdec_DenseVector *__pyx_v_self); /* proto */
+static void __pyx_pf_5_cdec_12SparseVector___dealloc__(CYTHON_UNUSED struct __pyx_obj_5_cdec_SparseVector *__pyx_v_self); /* proto */
+static PyObject *__pyx_pf_5_cdec_12SparseVector_2copy(struct __pyx_obj_5_cdec_SparseVector *__pyx_v_self); /* proto */
+static PyObject *__pyx_pf_5_cdec_12SparseVector_4__getitem__(struct __pyx_obj_5_cdec_SparseVector *__pyx_v_self, char *__pyx_v_fname); /* proto */
+static int __pyx_pf_5_cdec_12SparseVector_6__setitem__(struct __pyx_obj_5_cdec_SparseVector *__pyx_v_self, char *__pyx_v_fname, float __pyx_v_value); /* proto */
+static PyObject *__pyx_pf_5_cdec_12SparseVector_8__iter__(struct __pyx_obj_5_cdec_SparseVector *__pyx_v_self); /* proto */
+static PyObject *__pyx_pf_5_cdec_12SparseVector_11dot(struct __pyx_obj_5_cdec_SparseVector *__pyx_v_self, PyObject *__pyx_v_other); /* proto */
+static PyObject *__pyx_pf_5_cdec_12SparseVector_13__richcmp__(struct __pyx_obj_5_cdec_SparseVector *__pyx_v_x, struct __pyx_obj_5_cdec_SparseVector *__pyx_v_y, int __pyx_v_op); /* proto */
+static Py_ssize_t __pyx_pf_5_cdec_12SparseVector_15__len__(struct __pyx_obj_5_cdec_SparseVector *__pyx_v_self); /* proto */
+static int __pyx_pf_5_cdec_12SparseVector_17__contains__(struct __pyx_obj_5_cdec_SparseVector *__pyx_v_self, char *__pyx_v_fname); /* proto */
+static PyObject *__pyx_pf_5_cdec_12SparseVector_19__iadd__(struct __pyx_obj_5_cdec_SparseVector *__pyx_v_self, struct __pyx_obj_5_cdec_SparseVector *__pyx_v_other); /* proto */
+static PyObject *__pyx_pf_5_cdec_12SparseVector_21__isub__(struct __pyx_obj_5_cdec_SparseVector *__pyx_v_self, struct __pyx_obj_5_cdec_SparseVector *__pyx_v_other); /* proto */
+static PyObject *__pyx_pf_5_cdec_12SparseVector_23__imul__(struct __pyx_obj_5_cdec_SparseVector *__pyx_v_self, float __pyx_v_scalar); /* proto */
+#if PY_MAJOR_VERSION < 3
+static PyObject *__pyx_pf_5_cdec_12SparseVector_25__idiv__(struct __pyx_obj_5_cdec_SparseVector *__pyx_v_self, float __pyx_v_scalar); /* proto */
+#endif
+static PyObject *__pyx_pf_5_cdec_12SparseVector_27__add__(struct __pyx_obj_5_cdec_SparseVector *__pyx_v_x, struct __pyx_obj_5_cdec_SparseVector *__pyx_v_y); /* proto */
+static PyObject *__pyx_pf_5_cdec_12SparseVector_29__sub__(struct __pyx_obj_5_cdec_SparseVector *__pyx_v_x, struct __pyx_obj_5_cdec_SparseVector *__pyx_v_y); /* proto */
+static PyObject *__pyx_pf_5_cdec_12SparseVector_31__mul__(PyObject *__pyx_v_x, PyObject *__pyx_v_y); /* proto */
 #if PY_MAJOR_VERSION < 3
-static PyObject *__pyx_pf_5_cdec_12SparseVector_23__idiv__(struct __pyx_obj_5_cdec_SparseVector *__pyx_v_self, float __pyx_v_scalar); /* proto */
+static PyObject *__pyx_pf_5_cdec_12SparseVector_33__div__(PyObject *__pyx_v_x, PyObject *__pyx_v_y); /* proto */
 #endif
-static PyObject *__pyx_pf_5_cdec_12SparseVector_25__add__(struct __pyx_obj_5_cdec_SparseVector *__pyx_v_self, struct __pyx_obj_5_cdec_SparseVector *__pyx_v_other); /* proto */
-static PyObject *__pyx_pf_5_cdec_12SparseVector_27__sub__(struct __pyx_obj_5_cdec_SparseVector *__pyx_v_self, struct __pyx_obj_5_cdec_SparseVector *__pyx_v_other); /* proto */
 static void __pyx_pf_5_cdec_10Hypergraph___dealloc__(struct __pyx_obj_5_cdec_Hypergraph *__pyx_v_self); /* proto */
 static PyObject *__pyx_pf_5_cdec_10Hypergraph_2viterbi(struct __pyx_obj_5_cdec_Hypergraph *__pyx_v_self); /* proto */
 static PyObject *__pyx_pf_5_cdec_10Hypergraph_4viterbi_tree(struct __pyx_obj_5_cdec_Hypergraph *__pyx_v_self); /* proto */
@@ -895,11 +1061,12 @@ static PyObject *__pyx_pf_5_cdec_10Hypergraph_6viterbi_source_tree(struct __pyx_
 static PyObject *__pyx_pf_5_cdec_10Hypergraph_8viterbi_features(struct __pyx_obj_5_cdec_Hypergraph *__pyx_v_self); /* proto */
 static PyObject *__pyx_pf_5_cdec_10Hypergraph_10kbest(struct __pyx_obj_5_cdec_Hypergraph *__pyx_v_self, PyObject *__pyx_v_size); /* proto */
 static PyObject *__pyx_pf_5_cdec_10Hypergraph_13kbest_tree(struct __pyx_obj_5_cdec_Hypergraph *__pyx_v_self, PyObject *__pyx_v_size); /* proto */
-static PyObject *__pyx_pf_5_cdec_10Hypergraph_16sample(struct __pyx_obj_5_cdec_Hypergraph *__pyx_v_self, unsigned int __pyx_v_n); /* proto */
-static PyObject *__pyx_pf_5_cdec_10Hypergraph_19intersect(struct __pyx_obj_5_cdec_Hypergraph *__pyx_v_self, struct __pyx_obj_5_cdec_Lattice *__pyx_v_lat); /* proto */
-static PyObject *__pyx_pf_5_cdec_10Hypergraph_21prune(struct __pyx_obj_5_cdec_Hypergraph *__pyx_v_self, PyObject *__pyx_v_beam_alpha, PyObject *__pyx_v_density, PyObject *__pyx_v_kwargs); /* proto */
-static PyObject *__pyx_pf_5_cdec_10Hypergraph_23lattice(struct __pyx_obj_5_cdec_Hypergraph *__pyx_v_self); /* proto */
-static PyObject *__pyx_pf_5_cdec_10Hypergraph_25reweight(struct __pyx_obj_5_cdec_Hypergraph *__pyx_v_self, PyObject *__pyx_v_weights); /* proto */
+static PyObject *__pyx_pf_5_cdec_10Hypergraph_16kbest_features(struct __pyx_obj_5_cdec_Hypergraph *__pyx_v_self, PyObject *__pyx_v_size); /* proto */
+static PyObject *__pyx_pf_5_cdec_10Hypergraph_19sample(struct __pyx_obj_5_cdec_Hypergraph *__pyx_v_self, unsigned int __pyx_v_n); /* proto */
+static PyObject *__pyx_pf_5_cdec_10Hypergraph_22intersect(struct __pyx_obj_5_cdec_Hypergraph *__pyx_v_self, struct __pyx_obj_5_cdec_Lattice *__pyx_v_lat); /* proto */
+static PyObject *__pyx_pf_5_cdec_10Hypergraph_24prune(struct __pyx_obj_5_cdec_Hypergraph *__pyx_v_self, PyObject *__pyx_v_beam_alpha, PyObject *__pyx_v_density, PyObject *__pyx_v_kwargs); /* proto */
+static PyObject *__pyx_pf_5_cdec_10Hypergraph_26lattice(struct __pyx_obj_5_cdec_Hypergraph *__pyx_v_self); /* proto */
+static PyObject *__pyx_pf_5_cdec_10Hypergraph_28reweight(struct __pyx_obj_5_cdec_Hypergraph *__pyx_v_self, PyObject *__pyx_v_weights); /* proto */
 static int __pyx_pf_5_cdec_7Lattice___init__(struct __pyx_obj_5_cdec_Lattice *__pyx_v_self, PyObject *__pyx_v_inp); /* proto */
 static PyObject *__pyx_pf_5_cdec_7Lattice_2__getitem__(struct __pyx_obj_5_cdec_Lattice *__pyx_v_self, int __pyx_v_index); /* proto */
 static int __pyx_pf_5_cdec_7Lattice_4__setitem__(struct __pyx_obj_5_cdec_Lattice *__pyx_v_self, int __pyx_v_index, PyObject *__pyx_v_arcs); /* proto */
@@ -907,6 +1074,30 @@ static Py_ssize_t __pyx_pf_5_cdec_7Lattice_6__len__(struct __pyx_obj_5_cdec_Latt
 static PyObject *__pyx_pf_5_cdec_7Lattice_8__str__(struct __pyx_obj_5_cdec_Lattice *__pyx_v_self); /* proto */
 static PyObject *__pyx_pf_5_cdec_7Lattice_10__iter__(struct __pyx_obj_5_cdec_Lattice *__pyx_v_self); /* proto */
 static void __pyx_pf_5_cdec_7Lattice_13__dealloc__(CYTHON_UNUSED struct __pyx_obj_5_cdec_Lattice *__pyx_v_self); /* proto */
+static PyObject *__pyx_pf_5_cdec_9Candidate_5words___get__(struct __pyx_obj_5_cdec_Candidate *__pyx_v_self); /* proto */
+static PyObject *__pyx_pf_5_cdec_9Candidate_4fmap___get__(struct __pyx_obj_5_cdec_Candidate *__pyx_v_self); /* proto */
+static PyObject *__pyx_pf_5_cdec_9Candidate_5score___get__(struct __pyx_obj_5_cdec_Candidate *__pyx_v_self); /* proto */
+static int __pyx_pf_5_cdec_9Candidate_5score_2__set__(struct __pyx_obj_5_cdec_Candidate *__pyx_v_self, PyObject *__pyx_v_value); /* proto */
+static void __pyx_pf_5_cdec_15SufficientStats___dealloc__(CYTHON_UNUSED struct __pyx_obj_5_cdec_SufficientStats *__pyx_v_self); /* proto */
+static PyObject *__pyx_pf_5_cdec_15SufficientStats_5score___get__(struct __pyx_obj_5_cdec_SufficientStats *__pyx_v_self); /* proto */
+static PyObject *__pyx_pf_5_cdec_15SufficientStats_6detail___get__(struct __pyx_obj_5_cdec_SufficientStats *__pyx_v_self); /* proto */
+static Py_ssize_t __pyx_pf_5_cdec_15SufficientStats_2__len__(struct __pyx_obj_5_cdec_SufficientStats *__pyx_v_self); /* proto */
+static PyObject *__pyx_pf_5_cdec_15SufficientStats_4__iter__(struct __pyx_obj_5_cdec_SufficientStats *__pyx_v_self); /* proto */
+static PyObject *__pyx_pf_5_cdec_15SufficientStats_7__iadd__(struct __pyx_obj_5_cdec_SufficientStats *__pyx_v_self, struct __pyx_obj_5_cdec_SufficientStats *__pyx_v_other); /* proto */
+static PyObject *__pyx_pf_5_cdec_15SufficientStats_9__add__(struct __pyx_obj_5_cdec_SufficientStats *__pyx_v_x, struct __pyx_obj_5_cdec_SufficientStats *__pyx_v_y); /* proto */
+static int __pyx_pf_5_cdec_12CandidateSet___cinit__(struct __pyx_obj_5_cdec_CandidateSet *__pyx_v_self, struct __pyx_obj_5_cdec_SegmentEvaluator *__pyx_v_evaluator); /* proto */
+static void __pyx_pf_5_cdec_12CandidateSet_2__dealloc__(CYTHON_UNUSED struct __pyx_obj_5_cdec_CandidateSet *__pyx_v_self); /* proto */
+static Py_ssize_t __pyx_pf_5_cdec_12CandidateSet_4__len__(struct __pyx_obj_5_cdec_CandidateSet *__pyx_v_self); /* proto */
+static PyObject *__pyx_pf_5_cdec_12CandidateSet_6__getitem__(struct __pyx_obj_5_cdec_CandidateSet *__pyx_v_self, unsigned int __pyx_v_k); /* proto */
+static PyObject *__pyx_pf_5_cdec_12CandidateSet_8__iter__(struct __pyx_obj_5_cdec_CandidateSet *__pyx_v_self); /* proto */
+static PyObject *__pyx_pf_5_cdec_12CandidateSet_11add_kbest(struct __pyx_obj_5_cdec_CandidateSet *__pyx_v_self, struct __pyx_obj_5_cdec_Hypergraph *__pyx_v_hypergraph, unsigned int __pyx_v_k); /* proto */
+static void __pyx_pf_5_cdec_16SegmentEvaluator___dealloc__(CYTHON_UNUSED struct __pyx_obj_5_cdec_SegmentEvaluator *__pyx_v_self); /* proto */
+static PyObject *__pyx_pf_5_cdec_16SegmentEvaluator_2evaluate(struct __pyx_obj_5_cdec_SegmentEvaluator *__pyx_v_self, PyObject *__pyx_v_sentence); /* proto */
+static PyObject *__pyx_pf_5_cdec_16SegmentEvaluator_4candidate_set(struct __pyx_obj_5_cdec_SegmentEvaluator *__pyx_v_self); /* proto */
+static int __pyx_pf_5_cdec_6Scorer___cinit__(struct __pyx_obj_5_cdec_Scorer *__pyx_v_self, char *__pyx_v_name); /* proto */
+static void __pyx_pf_5_cdec_6Scorer_2__dealloc__(CYTHON_UNUSED struct __pyx_obj_5_cdec_Scorer *__pyx_v_self); /* proto */
+static PyObject *__pyx_pf_5_cdec_6Scorer_4__call__(struct __pyx_obj_5_cdec_Scorer *__pyx_v_self, PyObject *__pyx_v_refs); /* proto */
+static PyObject *__pyx_pf_5_cdec_6Scorer_6__str__(struct __pyx_obj_5_cdec_Scorer *__pyx_v_self); /* proto */
 static int __pyx_pf_5_cdec_7Decoder___cinit__(struct __pyx_obj_5_cdec_Decoder *__pyx_v_self, char *__pyx_v_config); /* proto */
 static void __pyx_pf_5_cdec_7Decoder_2__dealloc__(CYTHON_UNUSED struct __pyx_obj_5_cdec_Decoder *__pyx_v_self); /* proto */
 static PyObject *__pyx_pf_5_cdec_7Decoder_4read_weights(struct __pyx_obj_5_cdec_Decoder *__pyx_v_self, PyObject *__pyx_v_cfg); /* proto */
@@ -920,12 +1111,18 @@ static char __pyx_k_10[] = "csplit_preserve_full_word";
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 static char __pyx_k_13[] = "Cannot create lattice from %s";
 static char __pyx_k_14[] = "lattice index out of range";
-static char __pyx_k_21[] = "Cannot translate input type %s";
+static char __pyx_k_19[] = "Cannot convert type %s to str";
+static char __pyx_k_23[] = "Cannot translate input type %s";
+static char __pyx_k__k[] = "k";
+static char __pyx_k__TER[] = "TER";
 static char __pyx_k__dot[] = "dot";
 static char __pyx_k__inp[] = "inp";
 static char __pyx_k__plf[] = "plf";
+static char __pyx_k__BLEU[] = "BLEU";
 static char __pyx_k__eval[] = "eval";
+static char __pyx_k__name[] = "name";
 static char __pyx_k__open[] = "open";
+static char __pyx_k__refs[] = "refs";
 static char __pyx_k__self[] = "self";
 static char __pyx_k__utf8[] = "utf8";
 static char __pyx_k___cdec[] = "_cdec";
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 static char __pyx_k__encode[] = "encode";
 static char __pyx_k__density[] = "density";
 static char __pyx_k__grammar[] = "grammar";
+static char __pyx_k__IBM_BLEU[] = "IBM_BLEU";
 static char __pyx_k__KeyError[] = "KeyError";
 static char __pyx_k____exit__[] = "__exit__";
 static char __pyx_k____main__[] = "__main__";
 static char __pyx_k____test__[] = "__test__";
+static char __pyx_k__encoding[] = "encoding";
 static char __pyx_k__sentence[] = "sentence";
 static char __pyx_k__Exception[] = "Exception";
 static char __pyx_k__TypeError[] = "TypeError";
 static char __pyx_k____enter__[] = "__enter__";
 static char __pyx_k__enumerate[] = "enumerate";
+static char __pyx_k__evaluator[] = "evaluator";
 static char __pyx_k__IndexError[] = "IndexError";
-static char __pyx_k__ValueError[] = "ValueError";
 static char __pyx_k__beam_alpha[] = "beam_alpha";
+static char __pyx_k__hypergraph[] = "hypergraph";
 static char __pyx_k__ParseFailed[] = "ParseFailed";
 static char __pyx_k__NotImplemented[] = "NotImplemented";
 static PyObject *__pyx_kp_s_1;
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 static PyObject *__pyx_kp_s_11;
 static PyObject *__pyx_kp_s_13;
 static PyObject *__pyx_kp_s_14;
+static PyObject *__pyx_kp_s_19;
 static PyObject *__pyx_kp_s_2;
-static PyObject *__pyx_kp_s_21;
+static PyObject *__pyx_kp_s_23;
+static PyObject *__pyx_n_s__BLEU;
 static PyObject *__pyx_n_s__Exception;
+static PyObject *__pyx_n_s__IBM_BLEU;
 static PyObject *__pyx_n_s__IndexError;
 static PyObject *__pyx_n_s__KeyError;
 static PyObject *__pyx_n_s__NotImplemented;
 static PyObject *__pyx_n_s__ParseFailed;
+static PyObject *__pyx_n_s__TER;
 static PyObject *__pyx_n_s__TypeError;
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 static PyObject *__pyx_n_s____enter__;
 static PyObject *__pyx_n_s____exit__;
 static PyObject *__pyx_n_s____main__;
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 static PyObject *__pyx_n_s__density;
 static PyObject *__pyx_n_s__dot;
 static PyObject *__pyx_n_s__encode;
+static PyObject *__pyx_n_s__encoding;
 static PyObject *__pyx_n_s__enumerate;
 static PyObject *__pyx_n_s__eval;
+static PyObject *__pyx_n_s__evaluator;
 static PyObject *__pyx_n_s__grammar;
+static PyObject *__pyx_n_s__hypergraph;
 static PyObject *__pyx_n_s__inp;
+static PyObject *__pyx_n_s__k;
+static PyObject *__pyx_n_s__name;
 static PyObject *__pyx_n_s__open;
 static PyObject *__pyx_n_s__plf;
 static PyObject *__pyx_n_s__range;
+static PyObject *__pyx_n_s__refs;
 static PyObject *__pyx_n_s__self;
 static PyObject *__pyx_n_s__sentence;
 static PyObject *__pyx_n_s__split;
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 static PyObject *__pyx_k_tuple_16;
 static PyObject *__pyx_k_tuple_17;
 static PyObject *__pyx_k_tuple_18;
-static PyObject *__pyx_k_tuple_19;
 static PyObject *__pyx_k_tuple_20;
+static PyObject *__pyx_k_tuple_21;
+static PyObject *__pyx_k_tuple_22;
+static PyObject *__pyx_k_tuple_24;
+static PyObject *__pyx_k_tuple_25;
 
 /* Python wrapper */
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-static PyObject *__pyx_pw_5_cdec_11DenseVector_1__getitem__(PyObject *__pyx_v_self, PyObject *__pyx_arg_fname) {
+static Py_ssize_t __pyx_pw_5_cdec_11DenseVector_1__len__(PyObject *__pyx_v_self); /*proto*/
+static Py_ssize_t __pyx_pw_5_cdec_11DenseVector_1__len__(PyObject *__pyx_v_self) {
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+  __Pyx_RefNannyFinishContext();
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+ * 
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+ * 
+ */
+
+static Py_ssize_t __pyx_pf_5_cdec_11DenseVector___len__(struct __pyx_obj_5_cdec_DenseVector *__pyx_v_self) {
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+  __Pyx_RefNannyDeclarations
+  __Pyx_RefNannySetupContext("__len__", 0);
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+ * 
+ *     def __getitem__(self, char* fname):
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+/* Python wrapper */
+static PyObject *__pyx_pw_5_cdec_11DenseVector_3__getitem__(PyObject *__pyx_v_self, PyObject *__pyx_arg_fname); /*proto*/
+static PyObject *__pyx_pw_5_cdec_11DenseVector_3__getitem__(PyObject *__pyx_v_self, PyObject *__pyx_arg_fname) {
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+    __pyx_v_fname = PyBytes_AsString(__pyx_arg_fname); if (unlikely((!__pyx_v_fname) && PyErr_Occurred())) {__pyx_filename = __pyx_f[1]; __pyx_lineno = 9; __pyx_clineno = __LINE__; goto __pyx_L3_error;}
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+  __pyx_r = __pyx_pf_5_cdec_11DenseVector_2__getitem__(((struct __pyx_obj_5_cdec_DenseVector *)__pyx_v_self), ((char *)__pyx_v_fname));
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-/* "/Users/vchahun/Sandbox/cdec/python/src/vectors.pxi":6
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- *         cdef unsigned fid = FDConvert(fname)
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-static PyObject *__pyx_pf_5_cdec_11DenseVector___getitem__(struct __pyx_obj_5_cdec_DenseVector *__pyx_v_self, char *__pyx_v_fname) {
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+static PyObject *__pyx_pf_5_cdec_11DenseVector_2__getitem__(struct __pyx_obj_5_cdec_DenseVector *__pyx_v_self, char *__pyx_v_fname) {
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-  /* "/Users/vchahun/Sandbox/cdec/python/src/vectors.pxi":7
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-  /* "/Users/vchahun/Sandbox/cdec/python/src/vectors.pxi":8
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-    /* "/Users/vchahun/Sandbox/cdec/python/src/vectors.pxi":9
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+    /* "/Users/vchahun/Sandbox/cdec/python/src/vectors.pxi":12
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-    /* "/Users/vchahun/Sandbox/cdec/python/src/vectors.pxi":15
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+    /* "/Users/vchahun/Sandbox/cdec/python/src/vectors.pxi":19
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+    goto __pyx_L4;
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-  __pyx_L3:;
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-  /* "/Users/vchahun/Sandbox/cdec/python/src/vectors.pxi":16
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 /* Python wrapper */
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+static PyObject *__pyx_pw_5_cdec_11DenseVector_7__iter__(PyObject *__pyx_v_self); /*proto*/
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-/* "/Users/vchahun/Sandbox/cdec/python/src/vectors.pxi":18
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-static PyObject *__pyx_pf_5_cdec_11DenseVector_4__iter__(struct __pyx_obj_5_cdec_DenseVector *__pyx_v_self) {
+static PyObject *__pyx_pf_5_cdec_11DenseVector_6__iter__(struct __pyx_obj_5_cdec_DenseVector *__pyx_v_self) {
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+  if (unlikely(!__pyx_sent_value)) {__pyx_filename = __pyx_f[1]; __pyx_lineno = 22; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
 
-  /* "/Users/vchahun/Sandbox/cdec/python/src/vectors.pxi":20
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-    /* "/Users/vchahun/Sandbox/cdec/python/src/vectors.pxi":21
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-/* "/Users/vchahun/Sandbox/cdec/python/src/vectors.pxi":23
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+static PyObject *__pyx_pf_5_cdec_11DenseVector_9dot(struct __pyx_obj_5_cdec_DenseVector *__pyx_v_self, struct __pyx_obj_5_cdec_SparseVector *__pyx_v_other) {
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-  /* "/Users/vchahun/Sandbox/cdec/python/src/vectors.pxi":24
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+  __pyx_r = __pyx_pf_5_cdec_12SparseVector_17__contains__(((struct __pyx_obj_5_cdec_SparseVector *)__pyx_v_self), ((char *)__pyx_v_fname));
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+static int __pyx_pf_5_cdec_12SparseVector_17__contains__(struct __pyx_obj_5_cdec_SparseVector *__pyx_v_self, char *__pyx_v_fname) {
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-  /* "/Users/vchahun/Sandbox/cdec/python/src/vectors.pxi":75
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+static PyObject *__pyx_pw_5_cdec_12SparseVector_20__iadd__(PyObject *__pyx_v_self, PyObject *__pyx_v_other); /*proto*/
+static PyObject *__pyx_pw_5_cdec_12SparseVector_20__iadd__(PyObject *__pyx_v_self, PyObject *__pyx_v_other) {
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+  if (unlikely(!__Pyx_ArgTypeTest(((PyObject *)__pyx_v_other), __pyx_ptype_5_cdec_SparseVector, 1, "other", 0))) {__pyx_filename = __pyx_f[1]; __pyx_lineno = 84; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
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-/* "/Users/vchahun/Sandbox/cdec/python/src/vectors.pxi":77
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+static PyObject *__pyx_pf_5_cdec_12SparseVector_19__iadd__(struct __pyx_obj_5_cdec_SparseVector *__pyx_v_self, struct __pyx_obj_5_cdec_SparseVector *__pyx_v_other) {
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-  /* "/Users/vchahun/Sandbox/cdec/python/src/vectors.pxi":78
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-  /* "/Users/vchahun/Sandbox/cdec/python/src/vectors.pxi":79
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-static PyObject *__pyx_pw_5_cdec_12SparseVector_20__isub__(PyObject *__pyx_v_self, PyObject *__pyx_v_other) {
+static PyObject *__pyx_pw_5_cdec_12SparseVector_22__isub__(PyObject *__pyx_v_self, PyObject *__pyx_v_other); /*proto*/
+static PyObject *__pyx_pw_5_cdec_12SparseVector_22__isub__(PyObject *__pyx_v_self, PyObject *__pyx_v_other) {
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-  __pyx_r = __pyx_pf_5_cdec_12SparseVector_19__isub__(((struct __pyx_obj_5_cdec_SparseVector *)__pyx_v_self), ((struct __pyx_obj_5_cdec_SparseVector *)__pyx_v_other));
+  if (unlikely(!__Pyx_ArgTypeTest(((PyObject *)__pyx_v_other), __pyx_ptype_5_cdec_SparseVector, 1, "other", 0))) {__pyx_filename = __pyx_f[1]; __pyx_lineno = 88; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
+  __pyx_r = __pyx_pf_5_cdec_12SparseVector_21__isub__(((struct __pyx_obj_5_cdec_SparseVector *)__pyx_v_self), ((struct __pyx_obj_5_cdec_SparseVector *)__pyx_v_other));
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-/* "/Users/vchahun/Sandbox/cdec/python/src/vectors.pxi":81
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+static PyObject *__pyx_pf_5_cdec_12SparseVector_21__isub__(struct __pyx_obj_5_cdec_SparseVector *__pyx_v_self, struct __pyx_obj_5_cdec_SparseVector *__pyx_v_other) {
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-  /* "/Users/vchahun/Sandbox/cdec/python/src/vectors.pxi":82
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-  /* "/Users/vchahun/Sandbox/cdec/python/src/vectors.pxi":83
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+static PyObject *__pyx_pw_5_cdec_12SparseVector_24__imul__(PyObject *__pyx_v_self, PyObject *__pyx_arg_scalar); /*proto*/
+static PyObject *__pyx_pw_5_cdec_12SparseVector_24__imul__(PyObject *__pyx_v_self, PyObject *__pyx_arg_scalar) {
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+  __pyx_r = __pyx_pf_5_cdec_12SparseVector_23__imul__(((struct __pyx_obj_5_cdec_SparseVector *)__pyx_v_self), ((float)__pyx_v_scalar));
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-/* "/Users/vchahun/Sandbox/cdec/python/src/vectors.pxi":85
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-static PyObject *__pyx_pf_5_cdec_12SparseVector_21__imul__(struct __pyx_obj_5_cdec_SparseVector *__pyx_v_self, float __pyx_v_scalar) {
+static PyObject *__pyx_pf_5_cdec_12SparseVector_23__imul__(struct __pyx_obj_5_cdec_SparseVector *__pyx_v_self, float __pyx_v_scalar) {
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-  /* "/Users/vchahun/Sandbox/cdec/python/src/vectors.pxi":86
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-  /* "/Users/vchahun/Sandbox/cdec/python/src/vectors.pxi":87
+  /* "/Users/vchahun/Sandbox/cdec/python/src/vectors.pxi":94
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+  __pyx_r = __pyx_pf_5_cdec_12SparseVector_25__idiv__(((struct __pyx_obj_5_cdec_SparseVector *)__pyx_v_self), ((float)__pyx_v_scalar));
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+static PyObject *__pyx_pf_5_cdec_12SparseVector_25__idiv__(struct __pyx_obj_5_cdec_SparseVector *__pyx_v_self, float __pyx_v_scalar) {
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-  /* "/Users/vchahun/Sandbox/cdec/python/src/vectors.pxi":90
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-  /* "/Users/vchahun/Sandbox/cdec/python/src/vectors.pxi":91
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+  if (unlikely(!__Pyx_ArgTypeTest(((PyObject *)__pyx_v_x), __pyx_ptype_5_cdec_SparseVector, 1, "x", 0))) {__pyx_filename = __pyx_f[1]; __pyx_lineno = 100; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
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+  __pyx_r = __pyx_pf_5_cdec_12SparseVector_27__add__(((struct __pyx_obj_5_cdec_SparseVector *)__pyx_v_x), ((struct __pyx_obj_5_cdec_SparseVector *)__pyx_v_y));
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 static void __pyx_pw_5_cdec_10Hypergraph_1__dealloc__(PyObject *__pyx_v_self); /*proto*/
 static void __pyx_pw_5_cdec_10Hypergraph_1__dealloc__(PyObject *__pyx_v_self) {
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 /* Python wrapper */
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+/* "/Users/vchahun/Sandbox/cdec/python/src/hypergraph.pxi":91
  *     # TODO richer k-best/sample output (feature vectors, trees?)
  * 
  *     def intersect(self, Lattice lat):             # <<<<<<<<<<<<<<
@@ -3581,7 +4555,7 @@ static PyObject *__pyx_pw_5_cdec_10Hypergraph_20intersect(PyObject *__pyx_v_self
  * 
  */
 
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+static PyObject *__pyx_pf_5_cdec_10Hypergraph_22intersect(struct __pyx_obj_5_cdec_Hypergraph *__pyx_v_self, struct __pyx_obj_5_cdec_Lattice *__pyx_v_lat) {
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@@ -3590,7 +4564,7 @@ static PyObject *__pyx_pf_5_cdec_10Hypergraph_19intersect(struct __pyx_obj_5_cde
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-  /* "/Users/vchahun/Sandbox/cdec/python/src/hypergraph.pxi":71
+  /* "/Users/vchahun/Sandbox/cdec/python/src/hypergraph.pxi":92
  * 
  *     def intersect(self, Lattice lat):
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@@ -3598,7 +4572,7 @@ static PyObject *__pyx_pf_5_cdec_10Hypergraph_19intersect(struct __pyx_obj_5_cde
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+  __pyx_t_1 = __Pyx_PyBool_FromLong(HG::Intersect((__pyx_v_lat->lattice[0]), __pyx_v_self->hg)); if (unlikely(!__pyx_t_1)) {__pyx_filename = __pyx_f[2]; __pyx_lineno = 92; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
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@@ -3617,8 +4591,8 @@ static PyObject *__pyx_pf_5_cdec_10Hypergraph_19intersect(struct __pyx_obj_5_cde
 }
 
 /* Python wrapper */
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-static PyObject *__pyx_pw_5_cdec_10Hypergraph_22prune(PyObject *__pyx_v_self, PyObject *__pyx_args, PyObject *__pyx_kwds) {
+static PyObject *__pyx_pw_5_cdec_10Hypergraph_25prune(PyObject *__pyx_v_self, PyObject *__pyx_args, PyObject *__pyx_kwds); /*proto*/
+static PyObject *__pyx_pw_5_cdec_10Hypergraph_25prune(PyObject *__pyx_v_self, PyObject *__pyx_args, PyObject *__pyx_kwds) {
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+  __Pyx_RaiseArgtupleInvalid("prune", 0, 0, 2, PyTuple_GET_SIZE(__pyx_args)); {__pyx_filename = __pyx_f[2]; __pyx_lineno = 94; __pyx_clineno = __LINE__; goto __pyx_L3_error;}
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+  __pyx_r = __pyx_pf_5_cdec_10Hypergraph_24prune(((struct __pyx_obj_5_cdec_Hypergraph *)__pyx_v_self), __pyx_v_beam_alpha, __pyx_v_density, __pyx_v_kwargs);
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-/* "/Users/vchahun/Sandbox/cdec/python/src/hypergraph.pxi":73
+/* "/Users/vchahun/Sandbox/cdec/python/src/hypergraph.pxi":94
  *         return hypergraph.Intersect(lat.lattice[0], self.hg)
  * 
  *     def prune(self, beam_alpha=0, density=0, **kwargs):             # <<<<<<<<<<<<<<
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-static PyObject *__pyx_pf_5_cdec_10Hypergraph_21prune(struct __pyx_obj_5_cdec_Hypergraph *__pyx_v_self, PyObject *__pyx_v_beam_alpha, PyObject *__pyx_v_density, PyObject *__pyx_v_kwargs) {
+static PyObject *__pyx_pf_5_cdec_10Hypergraph_24prune(struct __pyx_obj_5_cdec_Hypergraph *__pyx_v_self, PyObject *__pyx_v_beam_alpha, PyObject *__pyx_v_density, PyObject *__pyx_v_kwargs) {
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@@ -3703,7 +4677,7 @@ static PyObject *__pyx_pf_5_cdec_10Hypergraph_21prune(struct __pyx_obj_5_cdec_Hy
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-  /* "/Users/vchahun/Sandbox/cdec/python/src/hypergraph.pxi":74
+  /* "/Users/vchahun/Sandbox/cdec/python/src/hypergraph.pxi":95
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-  /* "/Users/vchahun/Sandbox/cdec/python/src/hypergraph.pxi":75
+  /* "/Users/vchahun/Sandbox/cdec/python/src/hypergraph.pxi":96
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+  __pyx_t_1 = ((PyDict_Contains(((PyObject *)__pyx_v_kwargs), ((PyObject *)__pyx_n_s_10)))); if (unlikely(__pyx_t_1 < 0)) {__pyx_filename = __pyx_f[2]; __pyx_lineno = 96; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
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-    /* "/Users/vchahun/Sandbox/cdec/python/src/hypergraph.pxi":76
+    /* "/Users/vchahun/Sandbox/cdec/python/src/hypergraph.pxi":97
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-    /* "/Users/vchahun/Sandbox/cdec/python/src/hypergraph.pxi":77
+    /* "/Users/vchahun/Sandbox/cdec/python/src/hypergraph.pxi":98
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- * 
+ *         if preserve_mask:
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-  /* "/Users/vchahun/Sandbox/cdec/python/src/hypergraph.pxi":78
+  /* "/Users/vchahun/Sandbox/cdec/python/src/hypergraph.pxi":99
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  *         self.hg.PruneInsideOutside(beam_alpha, density, preserve_mask, False, 1, False)             # <<<<<<<<<<<<<<
+ *         if preserve_mask:
+ *             del preserve_mask
+ */
+  __pyx_t_2 = __pyx_PyFloat_AsDouble(__pyx_v_beam_alpha); if (unlikely((__pyx_t_2 == (double)-1) && PyErr_Occurred())) {__pyx_filename = __pyx_f[2]; __pyx_lineno = 99; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
+  __pyx_t_3 = __pyx_PyFloat_AsDouble(__pyx_v_density); if (unlikely((__pyx_t_3 == (double)-1) && PyErr_Occurred())) {__pyx_filename = __pyx_f[2]; __pyx_lineno = 99; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
+  __pyx_v_self->hg->PruneInsideOutside(__pyx_t_2, __pyx_t_3, __pyx_v_preserve_mask, 0, 1.0, 0);
+
+  /* "/Users/vchahun/Sandbox/cdec/python/src/hypergraph.pxi":100
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+ *         self.hg.PruneInsideOutside(beam_alpha, density, preserve_mask, False, 1, False)
+ *         if preserve_mask:             # <<<<<<<<<<<<<<
+ *             del preserve_mask
+ * 
+ */
+  __pyx_t_1 = (__pyx_v_preserve_mask != 0);
+  if (__pyx_t_1) {
+
+    /* "/Users/vchahun/Sandbox/cdec/python/src/hypergraph.pxi":101
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+ *         if preserve_mask:
+ *             del preserve_mask             # <<<<<<<<<<<<<<
  * 
  *     def lattice(self): # TODO direct hg -> lattice conversion in cdec
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-  __pyx_t_2 = __pyx_PyFloat_AsDouble(__pyx_v_beam_alpha); if (unlikely((__pyx_t_2 == (double)-1) && PyErr_Occurred())) {__pyx_filename = __pyx_f[2]; __pyx_lineno = 78; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
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-  __pyx_v_self->hg->PruneInsideOutside(__pyx_t_2, __pyx_t_3, __pyx_v_preserve_mask, 0, 1.0, 0);
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 /* Python wrapper */
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+/* "/Users/vchahun/Sandbox/cdec/python/src/hypergraph.pxi":103
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-static PyObject *__pyx_pf_5_cdec_10Hypergraph_23lattice(struct __pyx_obj_5_cdec_Hypergraph *__pyx_v_self) {
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-  /* "/Users/vchahun/Sandbox/cdec/python/src/hypergraph.pxi":81
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-  /* "/Users/vchahun/Sandbox/cdec/python/src/hypergraph.pxi":82
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+ *         cdef unsigned i
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+ *             del refv             # <<<<<<<<<<<<<<
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+ *         cdef SegmentEvaluator evaluator = SegmentEvaluator()
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+  /* "/Users/vchahun/Sandbox/cdec/python/src/mteval.pxi":131
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+ *         evaluator.metric = metric
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+ */
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+  /* "/Users/vchahun/Sandbox/cdec/python/src/mteval.pxi":132
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+ *         evaluator.metric = metric             # <<<<<<<<<<<<<<
+ *         evaluator.scorer = new shared_ptr[mteval.SegmentEvaluator](metric.CreateSegmentEvaluator(refsv[0]))
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+ *         del refsv # in theory should not delete but store in SegmentEvaluator
+ *         return evaluator             # <<<<<<<<<<<<<<
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+ *     def __str__(self):
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+  __pyx_r = Py_None; __Pyx_INCREF(Py_None);
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+  __pyx_L1_error:;
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+  __Pyx_XDECREF(__pyx_t_7);
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+/* Python wrapper */
+static PyObject *__pyx_pw_5_cdec_6Scorer_7__str__(PyObject *__pyx_v_self); /*proto*/
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+ * 
+ *     def __str__(self):             # <<<<<<<<<<<<<<
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+ * 
+ */
+
+static PyObject *__pyx_pf_5_cdec_6Scorer_6__str__(struct __pyx_obj_5_cdec_Scorer *__pyx_v_self) {
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+  __pyx_r = Py_None; __Pyx_INCREF(Py_None);
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 /* Python wrapper */
 static int __pyx_pw_5_cdec_7Decoder_1__cinit__(PyObject *__pyx_v_self, PyObject *__pyx_args, PyObject *__pyx_kwds); /*proto*/
 static int __pyx_pw_5_cdec_7Decoder_1__cinit__(PyObject *__pyx_v_self, PyObject *__pyx_args, PyObject *__pyx_kwds) {
@@ -5385,7 +8375,7 @@ static PyObject *__pyx_pf_5_cdec_7Decoder_4read_weights(struct __pyx_obj_5_cdec_
     }
     /*finally:*/ {
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-        __pyx_t_7 = PyObject_Call(__pyx_t_3, __pyx_k_tuple_19, NULL);
+        __pyx_t_7 = PyObject_Call(__pyx_t_3, __pyx_k_tuple_21, NULL);
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+    __pyx_t_3 = PyObject_Call(__pyx_t_1, ((PyObject *)__pyx_k_tuple_22), NULL); if (unlikely(!__pyx_t_3)) {__pyx_filename = __pyx_f[0]; __pyx_lineno = 38; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
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+    __pyx_t_3 = PyNumber_Remainder(((PyObject *)__pyx_kp_s_23), ((PyObject *)Py_TYPE(__pyx_v_sentence))); if (unlikely(!__pyx_t_3)) {__pyx_filename = __pyx_f[0]; __pyx_lineno = 44; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
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@@ -5858,7 +8848,7 @@ static PyObject *__pyx_sq_item_5_cdec_DenseVector(PyObject *o, Py_ssize_t i) {
 
 static int __pyx_mp_ass_subscript_5_cdec_DenseVector(PyObject *o, PyObject *i, PyObject *v) {
   if (v) {
-    return __pyx_pw_5_cdec_11DenseVector_3__setitem__(o, i, v);
+    return __pyx_pw_5_cdec_11DenseVector_5__setitem__(o, i, v);
   }
   else {
     PyErr_Format(PyExc_NotImplementedError,
@@ -5868,8 +8858,8 @@ static int __pyx_mp_ass_subscript_5_cdec_DenseVector(PyObject *o, PyObject *i, P
 }
 
 static PyMethodDef __pyx_methods_5_cdec_DenseVector[] = {
-  {__Pyx_NAMESTR("dot"), (PyCFunction)__pyx_pw_5_cdec_11DenseVector_8dot, METH_O, __Pyx_DOCSTR(0)},
-  {__Pyx_NAMESTR("tosparse"), (PyCFunction)__pyx_pw_5_cdec_11DenseVector_10tosparse, METH_NOARGS, __Pyx_DOCSTR(0)},
+  {__Pyx_NAMESTR("dot"), (PyCFunction)__pyx_pw_5_cdec_11DenseVector_10dot, METH_O, __Pyx_DOCSTR(0)},
+  {__Pyx_NAMESTR("tosparse"), (PyCFunction)__pyx_pw_5_cdec_11DenseVector_12tosparse, METH_NOARGS, __Pyx_DOCSTR(0)},
   {0, 0, 0, 0}
 };
 
@@ -5932,7 +8922,7 @@ static PyNumberMethods __pyx_tp_as_number_DenseVector = {
 };
 
 static PySequenceMethods __pyx_tp_as_sequence_DenseVector = {
-  0, /*sq_length*/
+  __pyx_pw_5_cdec_11DenseVector_1__len__, /*sq_length*/
   0, /*sq_concat*/
   0, /*sq_repeat*/
   __pyx_sq_item_5_cdec_DenseVector, /*sq_item*/
@@ -5945,8 +8935,8 @@ static PySequenceMethods __pyx_tp_as_sequence_DenseVector = {
 };
 
 static PyMappingMethods __pyx_tp_as_mapping_DenseVector = {
-  0, /*mp_length*/
-  __pyx_pw_5_cdec_11DenseVector_1__getitem__, /*mp_subscript*/
+  __pyx_pw_5_cdec_11DenseVector_1__len__, /*mp_length*/
+  __pyx_pw_5_cdec_11DenseVector_3__getitem__, /*mp_subscript*/
   __pyx_mp_ass_subscript_5_cdec_DenseVector, /*mp_ass_subscript*/
 };
 
@@ -6001,7 +8991,7 @@ static PyTypeObject __pyx_type_5_cdec_DenseVector = {
   0, /*tp_clear*/
   0, /*tp_richcompare*/
   0, /*tp_weaklistoffset*/
-  __pyx_pw_5_cdec_11DenseVector_5__iter__, /*tp_iter*/
+  __pyx_pw_5_cdec_11DenseVector_7__iter__, /*tp_iter*/
   0, /*tp_iternext*/
   __pyx_methods_5_cdec_DenseVector, /*tp_methods*/
   0, /*tp_members*/
@@ -6034,6 +9024,15 @@ static PyObject *__pyx_tp_new_5_cdec_SparseVector(PyTypeObject *t, PyObject *a,
 }
 
 static void __pyx_tp_dealloc_5_cdec_SparseVector(PyObject *o) {
+  {
+    PyObject *etype, *eval, *etb;
+    PyErr_Fetch(&etype, &eval, &etb);
+    ++Py_REFCNT(o);
+    __pyx_pw_5_cdec_12SparseVector_1__dealloc__(o);
+    if (PyErr_Occurred()) PyErr_WriteUnraisable(o);
+    --Py_REFCNT(o);
+    PyErr_Restore(etype, eval, etb);
+  }
   (*Py_TYPE(o)->tp_free)(o);
 }
 static PyObject *__pyx_sq_item_5_cdec_SparseVector(PyObject *o, Py_ssize_t i) {
@@ -6046,7 +9045,7 @@ static PyObject *__pyx_sq_item_5_cdec_SparseVector(PyObject *o, Py_ssize_t i) {
 
 static int __pyx_mp_ass_subscript_5_cdec_SparseVector(PyObject *o, PyObject *i, PyObject *v) {
   if (v) {
-    return __pyx_pw_5_cdec_12SparseVector_3__setitem__(o, i, v);
+    return __pyx_pw_5_cdec_12SparseVector_7__setitem__(o, i, v);
   }
   else {
     PyErr_Format(PyExc_NotImplementedError,
@@ -6056,17 +9055,17 @@ static int __pyx_mp_ass_subscript_5_cdec_SparseVector(PyObject *o, PyObject *i,
 }
 
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-  {__Pyx_NAMESTR("dot"), (PyCFunction)__pyx_pw_5_cdec_12SparseVector_8dot, METH_O, __Pyx_DOCSTR(0)},
-  {__Pyx_NAMESTR("todense"), (PyCFunction)__pyx_pw_5_cdec_12SparseVector_10todense, METH_NOARGS, __Pyx_DOCSTR(0)},
+  {__Pyx_NAMESTR("copy"), (PyCFunction)__pyx_pw_5_cdec_12SparseVector_3copy, METH_NOARGS, __Pyx_DOCSTR(0)},
+  {__Pyx_NAMESTR("dot"), (PyCFunction)__pyx_pw_5_cdec_12SparseVector_12dot, METH_O, __Pyx_DOCSTR(0)},
   {0, 0, 0, 0}
 };
 
 static PyNumberMethods __pyx_tp_as_number_SparseVector = {
-  __pyx_pw_5_cdec_12SparseVector_26__add__, /*nb_add*/
-  __pyx_pw_5_cdec_12SparseVector_28__sub__, /*nb_subtract*/
-  0, /*nb_multiply*/
+  __pyx_pw_5_cdec_12SparseVector_28__add__, /*nb_add*/
+  __pyx_pw_5_cdec_12SparseVector_30__sub__, /*nb_subtract*/
+  __pyx_pw_5_cdec_12SparseVector_32__mul__, /*nb_multiply*/
   #if PY_MAJOR_VERSION < 3
-  0, /*nb_divide*/
+  __pyx_pw_5_cdec_12SparseVector_34__div__, /*nb_divide*/
   #endif
   0, /*nb_remainder*/
   0, /*nb_divmod*/
@@ -6097,11 +9096,11 @@ static PyNumberMethods __pyx_tp_as_number_SparseVector = {
   #if PY_MAJOR_VERSION < 3
   0, /*nb_hex*/
   #endif
-  __pyx_pw_5_cdec_12SparseVector_18__iadd__, /*nb_inplace_add*/
-  __pyx_pw_5_cdec_12SparseVector_20__isub__, /*nb_inplace_subtract*/
-  __pyx_pw_5_cdec_12SparseVector_22__imul__, /*nb_inplace_multiply*/
+  __pyx_pw_5_cdec_12SparseVector_20__iadd__, /*nb_inplace_add*/
+  __pyx_pw_5_cdec_12SparseVector_22__isub__, /*nb_inplace_subtract*/
+  __pyx_pw_5_cdec_12SparseVector_24__imul__, /*nb_inplace_multiply*/
   #if PY_MAJOR_VERSION < 3
-  __pyx_pw_5_cdec_12SparseVector_24__idiv__, /*nb_inplace_divide*/
+  __pyx_pw_5_cdec_12SparseVector_26__idiv__, /*nb_inplace_divide*/
   #endif
   0, /*nb_inplace_remainder*/
   0, /*nb_inplace_power*/
@@ -6120,21 +9119,21 @@ static PyNumberMethods __pyx_tp_as_number_SparseVector = {
 };
 
 static PySequenceMethods __pyx_tp_as_sequence_SparseVector = {
-  __pyx_pw_5_cdec_12SparseVector_14__len__, /*sq_length*/
+  __pyx_pw_5_cdec_12SparseVector_16__len__, /*sq_length*/
   0, /*sq_concat*/
   0, /*sq_repeat*/
   __pyx_sq_item_5_cdec_SparseVector, /*sq_item*/
   0, /*sq_slice*/
   0, /*sq_ass_item*/
   0, /*sq_ass_slice*/
-  __pyx_pw_5_cdec_12SparseVector_16__contains__, /*sq_contains*/
+  __pyx_pw_5_cdec_12SparseVector_18__contains__, /*sq_contains*/
   0, /*sq_inplace_concat*/
   0, /*sq_inplace_repeat*/
 };
 
 static PyMappingMethods __pyx_tp_as_mapping_SparseVector = {
-  __pyx_pw_5_cdec_12SparseVector_14__len__, /*mp_length*/
-  __pyx_pw_5_cdec_12SparseVector_1__getitem__, /*mp_subscript*/
+  __pyx_pw_5_cdec_12SparseVector_16__len__, /*mp_length*/
+  __pyx_pw_5_cdec_12SparseVector_5__getitem__, /*mp_subscript*/
   __pyx_mp_ass_subscript_5_cdec_SparseVector, /*mp_ass_subscript*/
 };
 
@@ -6187,9 +9186,9 @@ static PyTypeObject __pyx_type_5_cdec_SparseVector = {
   0, /*tp_doc*/
   0, /*tp_traverse*/
   0, /*tp_clear*/
-  __pyx_pw_5_cdec_12SparseVector_12__richcmp__, /*tp_richcompare*/
+  __pyx_pw_5_cdec_12SparseVector_14__richcmp__, /*tp_richcompare*/
   0, /*tp_weaklistoffset*/
-  __pyx_pw_5_cdec_12SparseVector_5__iter__, /*tp_iter*/
+  __pyx_pw_5_cdec_12SparseVector_9__iter__, /*tp_iter*/
   0, /*tp_iternext*/
   __pyx_methods_5_cdec_SparseVector, /*tp_methods*/
   0, /*tp_members*/
@@ -6241,11 +9240,12 @@ static PyMethodDef __pyx_methods_5_cdec_Hypergraph[] = {
   {__Pyx_NAMESTR("viterbi_features"), (PyCFunction)__pyx_pw_5_cdec_10Hypergraph_9viterbi_features, METH_NOARGS, __Pyx_DOCSTR(0)},
   {__Pyx_NAMESTR("kbest"), (PyCFunction)__pyx_pw_5_cdec_10Hypergraph_11kbest, METH_O, __Pyx_DOCSTR(0)},
   {__Pyx_NAMESTR("kbest_tree"), (PyCFunction)__pyx_pw_5_cdec_10Hypergraph_14kbest_tree, METH_O, __Pyx_DOCSTR(0)},
-  {__Pyx_NAMESTR("sample"), (PyCFunction)__pyx_pw_5_cdec_10Hypergraph_17sample, METH_O, __Pyx_DOCSTR(0)},
-  {__Pyx_NAMESTR("intersect"), (PyCFunction)__pyx_pw_5_cdec_10Hypergraph_20intersect, METH_O, __Pyx_DOCSTR(0)},
-  {__Pyx_NAMESTR("prune"), (PyCFunction)__pyx_pw_5_cdec_10Hypergraph_22prune, METH_VARARGS|METH_KEYWORDS, __Pyx_DOCSTR(0)},
-  {__Pyx_NAMESTR("lattice"), (PyCFunction)__pyx_pw_5_cdec_10Hypergraph_24lattice, METH_NOARGS, __Pyx_DOCSTR(0)},
-  {__Pyx_NAMESTR("reweight"), (PyCFunction)__pyx_pw_5_cdec_10Hypergraph_26reweight, METH_O, __Pyx_DOCSTR(0)},
+  {__Pyx_NAMESTR("kbest_features"), (PyCFunction)__pyx_pw_5_cdec_10Hypergraph_17kbest_features, METH_O, __Pyx_DOCSTR(0)},
+  {__Pyx_NAMESTR("sample"), (PyCFunction)__pyx_pw_5_cdec_10Hypergraph_20sample, METH_O, __Pyx_DOCSTR(0)},
+  {__Pyx_NAMESTR("intersect"), (PyCFunction)__pyx_pw_5_cdec_10Hypergraph_23intersect, METH_O, __Pyx_DOCSTR(0)},
+  {__Pyx_NAMESTR("prune"), (PyCFunction)__pyx_pw_5_cdec_10Hypergraph_25prune, METH_VARARGS|METH_KEYWORDS, __Pyx_DOCSTR(0)},
+  {__Pyx_NAMESTR("lattice"), (PyCFunction)__pyx_pw_5_cdec_10Hypergraph_27lattice, METH_NOARGS, __Pyx_DOCSTR(0)},
+  {__Pyx_NAMESTR("reweight"), (PyCFunction)__pyx_pw_5_cdec_10Hypergraph_29reweight, METH_O, __Pyx_DOCSTR(0)},
   {0, 0, 0, 0}
 };
 
@@ -6598,6 +9598,941 @@ static PyTypeObject __pyx_type_5_cdec_Lattice = {
   #endif
 };
 
+static PyObject *__pyx_tp_new_5_cdec_Candidate(PyTypeObject *t, PyObject *a, PyObject *k) {
+  PyObject *o = (*t->tp_alloc)(t, 0);
+  if (!o) return 0;
+  return o;
+}
+
+static void __pyx_tp_dealloc_5_cdec_Candidate(PyObject *o) {
+  (*Py_TYPE(o)->tp_free)(o);
+}
+
+static PyObject *__pyx_getprop_5_cdec_9Candidate_words(PyObject *o, void *x) {
+  return __pyx_pw_5_cdec_9Candidate_5words_1__get__(o);
+}
+
+static PyObject *__pyx_getprop_5_cdec_9Candidate_fmap(PyObject *o, void *x) {
+  return __pyx_pw_5_cdec_9Candidate_4fmap_1__get__(o);
+}
+
+static PyObject *__pyx_getprop_5_cdec_9Candidate_score(PyObject *o, void *x) {
+  return __pyx_pw_5_cdec_9Candidate_5score_1__get__(o);
+}
+
+static int __pyx_setprop_5_cdec_9Candidate_score(PyObject *o, PyObject *v, void *x) {
+  if (v) {
+    return __pyx_pw_5_cdec_9Candidate_5score_3__set__(o, v);
+  }
+  else {
+    PyErr_SetString(PyExc_NotImplementedError, "__del__");
+    return -1;
+  }
+}
+
+static PyMethodDef __pyx_methods_5_cdec_Candidate[] = {
+  {0, 0, 0, 0}
+};
+
+static struct PyGetSetDef __pyx_getsets_5_cdec_Candidate[] = {
+  {(char *)"words", __pyx_getprop_5_cdec_9Candidate_words, 0, 0, 0},
+  {(char *)"fmap", __pyx_getprop_5_cdec_9Candidate_fmap, 0, 0, 0},
+  {(char *)"score", __pyx_getprop_5_cdec_9Candidate_score, __pyx_setprop_5_cdec_9Candidate_score, 0, 0},
+  {0, 0, 0, 0, 0}
+};
+
+static PyNumberMethods __pyx_tp_as_number_Candidate = {
+  0, /*nb_add*/
+  0, /*nb_subtract*/
+  0, /*nb_multiply*/
+  #if PY_MAJOR_VERSION < 3
+  0, /*nb_divide*/
+  #endif
+  0, /*nb_remainder*/
+  0, /*nb_divmod*/
+  0, /*nb_power*/
+  0, /*nb_negative*/
+  0, /*nb_positive*/
+  0, /*nb_absolute*/
+  0, /*nb_nonzero*/
+  0, /*nb_invert*/
+  0, /*nb_lshift*/
+  0, /*nb_rshift*/
+  0, /*nb_and*/
+  0, /*nb_xor*/
+  0, /*nb_or*/
+  #if PY_MAJOR_VERSION < 3
+  0, /*nb_coerce*/
+  #endif
+  0, /*nb_int*/
+  #if PY_MAJOR_VERSION < 3
+  0, /*nb_long*/
+  #else
+  0, /*reserved*/
+  #endif
+  0, /*nb_float*/
+  #if PY_MAJOR_VERSION < 3
+  0, /*nb_oct*/
+  #endif
+  #if PY_MAJOR_VERSION < 3
+  0, /*nb_hex*/
+  #endif
+  0, /*nb_inplace_add*/
+  0, /*nb_inplace_subtract*/
+  0, /*nb_inplace_multiply*/
+  #if PY_MAJOR_VERSION < 3
+  0, /*nb_inplace_divide*/
+  #endif
+  0, /*nb_inplace_remainder*/
+  0, /*nb_inplace_power*/
+  0, /*nb_inplace_lshift*/
+  0, /*nb_inplace_rshift*/
+  0, /*nb_inplace_and*/
+  0, /*nb_inplace_xor*/
+  0, /*nb_inplace_or*/
+  0, /*nb_floor_divide*/
+  0, /*nb_true_divide*/
+  0, /*nb_inplace_floor_divide*/
+  0, /*nb_inplace_true_divide*/
+  #if PY_VERSION_HEX >= 0x02050000
+  0, /*nb_index*/
+  #endif
+};
+
+static PySequenceMethods __pyx_tp_as_sequence_Candidate = {
+  0, /*sq_length*/
+  0, /*sq_concat*/
+  0, /*sq_repeat*/
+  0, /*sq_item*/
+  0, /*sq_slice*/
+  0, /*sq_ass_item*/
+  0, /*sq_ass_slice*/
+  0, /*sq_contains*/
+  0, /*sq_inplace_concat*/
+  0, /*sq_inplace_repeat*/
+};
+
+static PyMappingMethods __pyx_tp_as_mapping_Candidate = {
+  0, /*mp_length*/
+  0, /*mp_subscript*/
+  0, /*mp_ass_subscript*/
+};
+
+static PyBufferProcs __pyx_tp_as_buffer_Candidate = {
+  #if PY_MAJOR_VERSION < 3
+  0, /*bf_getreadbuffer*/
+  #endif
+  #if PY_MAJOR_VERSION < 3
+  0, /*bf_getwritebuffer*/
+  #endif
+  #if PY_MAJOR_VERSION < 3
+  0, /*bf_getsegcount*/
+  #endif
+  #if PY_MAJOR_VERSION < 3
+  0, /*bf_getcharbuffer*/
+  #endif
+  #if PY_VERSION_HEX >= 0x02060000
+  0, /*bf_getbuffer*/
+  #endif
+  #if PY_VERSION_HEX >= 0x02060000
+  0, /*bf_releasebuffer*/
+  #endif
+};
+
+static PyTypeObject __pyx_type_5_cdec_Candidate = {
+  PyVarObject_HEAD_INIT(0, 0)
+  __Pyx_NAMESTR("_cdec.Candidate"), /*tp_name*/
+  sizeof(struct __pyx_obj_5_cdec_Candidate), /*tp_basicsize*/
+  0, /*tp_itemsize*/
+  __pyx_tp_dealloc_5_cdec_Candidate, /*tp_dealloc*/
+  0, /*tp_print*/
+  0, /*tp_getattr*/
+  0, /*tp_setattr*/
+  #if PY_MAJOR_VERSION < 3
+  0, /*tp_compare*/
+  #else
+  0, /*reserved*/
+  #endif
+  0, /*tp_repr*/
+  &__pyx_tp_as_number_Candidate, /*tp_as_number*/
+  &__pyx_tp_as_sequence_Candidate, /*tp_as_sequence*/
+  &__pyx_tp_as_mapping_Candidate, /*tp_as_mapping*/
+  0, /*tp_hash*/
+  0, /*tp_call*/
+  0, /*tp_str*/
+  0, /*tp_getattro*/
+  0, /*tp_setattro*/
+  &__pyx_tp_as_buffer_Candidate, /*tp_as_buffer*/
+  Py_TPFLAGS_DEFAULT|Py_TPFLAGS_CHECKTYPES|Py_TPFLAGS_HAVE_NEWBUFFER|Py_TPFLAGS_BASETYPE, /*tp_flags*/
+  0, /*tp_doc*/
+  0, /*tp_traverse*/
+  0, /*tp_clear*/
+  0, /*tp_richcompare*/
+  0, /*tp_weaklistoffset*/
+  0, /*tp_iter*/
+  0, /*tp_iternext*/
+  __pyx_methods_5_cdec_Candidate, /*tp_methods*/
+  0, /*tp_members*/
+  __pyx_getsets_5_cdec_Candidate, /*tp_getset*/
+  0, /*tp_base*/
+  0, /*tp_dict*/
+  0, /*tp_descr_get*/
+  0, /*tp_descr_set*/
+  0, /*tp_dictoffset*/
+  0, /*tp_init*/
+  0, /*tp_alloc*/
+  __pyx_tp_new_5_cdec_Candidate, /*tp_new*/
+  0, /*tp_free*/
+  0, /*tp_is_gc*/
+  0, /*tp_bases*/
+  0, /*tp_mro*/
+  0, /*tp_cache*/
+  0, /*tp_subclasses*/
+  0, /*tp_weaklist*/
+  0, /*tp_del*/
+  #if PY_VERSION_HEX >= 0x02060000
+  0, /*tp_version_tag*/
+  #endif
+};
+
+static PyObject *__pyx_tp_new_5_cdec_SufficientStats(PyTypeObject *t, PyObject *a, PyObject *k) {
+  PyObject *o = (*t->tp_alloc)(t, 0);
+  if (!o) return 0;
+  return o;
+}
+
+static void __pyx_tp_dealloc_5_cdec_SufficientStats(PyObject *o) {
+  {
+    PyObject *etype, *eval, *etb;
+    PyErr_Fetch(&etype, &eval, &etb);
+    ++Py_REFCNT(o);
+    __pyx_pw_5_cdec_15SufficientStats_1__dealloc__(o);
+    if (PyErr_Occurred()) PyErr_WriteUnraisable(o);
+    --Py_REFCNT(o);
+    PyErr_Restore(etype, eval, etb);
+  }
+  (*Py_TYPE(o)->tp_free)(o);
+}
+
+static PyObject *__pyx_getprop_5_cdec_15SufficientStats_score(PyObject *o, void *x) {
+  return __pyx_pw_5_cdec_15SufficientStats_5score_1__get__(o);
+}
+
+static PyObject *__pyx_getprop_5_cdec_15SufficientStats_detail(PyObject *o, void *x) {
+  return __pyx_pw_5_cdec_15SufficientStats_6detail_1__get__(o);
+}
+
+static PyMethodDef __pyx_methods_5_cdec_SufficientStats[] = {
+  {0, 0, 0, 0}
+};
+
+static struct PyGetSetDef __pyx_getsets_5_cdec_SufficientStats[] = {
+  {(char *)"score", __pyx_getprop_5_cdec_15SufficientStats_score, 0, 0, 0},
+  {(char *)"detail", __pyx_getprop_5_cdec_15SufficientStats_detail, 0, 0, 0},
+  {0, 0, 0, 0, 0}
+};
+
+static PyNumberMethods __pyx_tp_as_number_SufficientStats = {
+  __pyx_pw_5_cdec_15SufficientStats_10__add__, /*nb_add*/
+  0, /*nb_subtract*/
+  0, /*nb_multiply*/
+  #if PY_MAJOR_VERSION < 3
+  0, /*nb_divide*/
+  #endif
+  0, /*nb_remainder*/
+  0, /*nb_divmod*/
+  0, /*nb_power*/
+  0, /*nb_negative*/
+  0, /*nb_positive*/
+  0, /*nb_absolute*/
+  0, /*nb_nonzero*/
+  0, /*nb_invert*/
+  0, /*nb_lshift*/
+  0, /*nb_rshift*/
+  0, /*nb_and*/
+  0, /*nb_xor*/
+  0, /*nb_or*/
+  #if PY_MAJOR_VERSION < 3
+  0, /*nb_coerce*/
+  #endif
+  0, /*nb_int*/
+  #if PY_MAJOR_VERSION < 3
+  0, /*nb_long*/
+  #else
+  0, /*reserved*/
+  #endif
+  0, /*nb_float*/
+  #if PY_MAJOR_VERSION < 3
+  0, /*nb_oct*/
+  #endif
+  #if PY_MAJOR_VERSION < 3
+  0, /*nb_hex*/
+  #endif
+  __pyx_pw_5_cdec_15SufficientStats_8__iadd__, /*nb_inplace_add*/
+  0, /*nb_inplace_subtract*/
+  0, /*nb_inplace_multiply*/
+  #if PY_MAJOR_VERSION < 3
+  0, /*nb_inplace_divide*/
+  #endif
+  0, /*nb_inplace_remainder*/
+  0, /*nb_inplace_power*/
+  0, /*nb_inplace_lshift*/
+  0, /*nb_inplace_rshift*/
+  0, /*nb_inplace_and*/
+  0, /*nb_inplace_xor*/
+  0, /*nb_inplace_or*/
+  0, /*nb_floor_divide*/
+  0, /*nb_true_divide*/
+  0, /*nb_inplace_floor_divide*/
+  0, /*nb_inplace_true_divide*/
+  #if PY_VERSION_HEX >= 0x02050000
+  0, /*nb_index*/
+  #endif
+};
+
+static PySequenceMethods __pyx_tp_as_sequence_SufficientStats = {
+  __pyx_pw_5_cdec_15SufficientStats_3__len__, /*sq_length*/
+  0, /*sq_concat*/
+  0, /*sq_repeat*/
+  0, /*sq_item*/
+  0, /*sq_slice*/
+  0, /*sq_ass_item*/
+  0, /*sq_ass_slice*/
+  0, /*sq_contains*/
+  0, /*sq_inplace_concat*/
+  0, /*sq_inplace_repeat*/
+};
+
+static PyMappingMethods __pyx_tp_as_mapping_SufficientStats = {
+  __pyx_pw_5_cdec_15SufficientStats_3__len__, /*mp_length*/
+  0, /*mp_subscript*/
+  0, /*mp_ass_subscript*/
+};
+
+static PyBufferProcs __pyx_tp_as_buffer_SufficientStats = {
+  #if PY_MAJOR_VERSION < 3
+  0, /*bf_getreadbuffer*/
+  #endif
+  #if PY_MAJOR_VERSION < 3
+  0, /*bf_getwritebuffer*/
+  #endif
+  #if PY_MAJOR_VERSION < 3
+  0, /*bf_getsegcount*/
+  #endif
+  #if PY_MAJOR_VERSION < 3
+  0, /*bf_getcharbuffer*/
+  #endif
+  #if PY_VERSION_HEX >= 0x02060000
+  0, /*bf_getbuffer*/
+  #endif
+  #if PY_VERSION_HEX >= 0x02060000
+  0, /*bf_releasebuffer*/
+  #endif
+};
+
+static PyTypeObject __pyx_type_5_cdec_SufficientStats = {
+  PyVarObject_HEAD_INIT(0, 0)
+  __Pyx_NAMESTR("_cdec.SufficientStats"), /*tp_name*/
+  sizeof(struct __pyx_obj_5_cdec_SufficientStats), /*tp_basicsize*/
+  0, /*tp_itemsize*/
+  __pyx_tp_dealloc_5_cdec_SufficientStats, /*tp_dealloc*/
+  0, /*tp_print*/
+  0, /*tp_getattr*/
+  0, /*tp_setattr*/
+  #if PY_MAJOR_VERSION < 3
+  0, /*tp_compare*/
+  #else
+  0, /*reserved*/
+  #endif
+  0, /*tp_repr*/
+  &__pyx_tp_as_number_SufficientStats, /*tp_as_number*/
+  &__pyx_tp_as_sequence_SufficientStats, /*tp_as_sequence*/
+  &__pyx_tp_as_mapping_SufficientStats, /*tp_as_mapping*/
+  0, /*tp_hash*/
+  0, /*tp_call*/
+  0, /*tp_str*/
+  0, /*tp_getattro*/
+  0, /*tp_setattro*/
+  &__pyx_tp_as_buffer_SufficientStats, /*tp_as_buffer*/
+  Py_TPFLAGS_DEFAULT|Py_TPFLAGS_CHECKTYPES|Py_TPFLAGS_HAVE_NEWBUFFER|Py_TPFLAGS_BASETYPE, /*tp_flags*/
+  0, /*tp_doc*/
+  0, /*tp_traverse*/
+  0, /*tp_clear*/
+  0, /*tp_richcompare*/
+  0, /*tp_weaklistoffset*/
+  __pyx_pw_5_cdec_15SufficientStats_5__iter__, /*tp_iter*/
+  0, /*tp_iternext*/
+  __pyx_methods_5_cdec_SufficientStats, /*tp_methods*/
+  0, /*tp_members*/
+  __pyx_getsets_5_cdec_SufficientStats, /*tp_getset*/
+  0, /*tp_base*/
+  0, /*tp_dict*/
+  0, /*tp_descr_get*/
+  0, /*tp_descr_set*/
+  0, /*tp_dictoffset*/
+  0, /*tp_init*/
+  0, /*tp_alloc*/
+  __pyx_tp_new_5_cdec_SufficientStats, /*tp_new*/
+  0, /*tp_free*/
+  0, /*tp_is_gc*/
+  0, /*tp_bases*/
+  0, /*tp_mro*/
+  0, /*tp_cache*/
+  0, /*tp_subclasses*/
+  0, /*tp_weaklist*/
+  0, /*tp_del*/
+  #if PY_VERSION_HEX >= 0x02060000
+  0, /*tp_version_tag*/
+  #endif
+};
+
+static PyObject *__pyx_tp_new_5_cdec_CandidateSet(PyTypeObject *t, PyObject *a, PyObject *k) {
+  PyObject *o = (*t->tp_alloc)(t, 0);
+  if (!o) return 0;
+  if (__pyx_pw_5_cdec_12CandidateSet_1__cinit__(o, a, k) < 0) {
+    Py_DECREF(o); o = 0;
+  }
+  return o;
+}
+
+static void __pyx_tp_dealloc_5_cdec_CandidateSet(PyObject *o) {
+  {
+    PyObject *etype, *eval, *etb;
+    PyErr_Fetch(&etype, &eval, &etb);
+    ++Py_REFCNT(o);
+    __pyx_pw_5_cdec_12CandidateSet_3__dealloc__(o);
+    if (PyErr_Occurred()) PyErr_WriteUnraisable(o);
+    --Py_REFCNT(o);
+    PyErr_Restore(etype, eval, etb);
+  }
+  (*Py_TYPE(o)->tp_free)(o);
+}
+static PyObject *__pyx_sq_item_5_cdec_CandidateSet(PyObject *o, Py_ssize_t i) {
+  PyObject *r;
+  PyObject *x = PyInt_FromSsize_t(i); if(!x) return 0;
+  r = Py_TYPE(o)->tp_as_mapping->mp_subscript(o, x);
+  Py_DECREF(x);
+  return r;
+}
+
+static PyMethodDef __pyx_methods_5_cdec_CandidateSet[] = {
+  {__Pyx_NAMESTR("add_kbest"), (PyCFunction)__pyx_pw_5_cdec_12CandidateSet_12add_kbest, METH_VARARGS|METH_KEYWORDS, __Pyx_DOCSTR(0)},
+  {0, 0, 0, 0}
+};
+
+static PyNumberMethods __pyx_tp_as_number_CandidateSet = {
+  0, /*nb_add*/
+  0, /*nb_subtract*/
+  0, /*nb_multiply*/
+  #if PY_MAJOR_VERSION < 3
+  0, /*nb_divide*/
+  #endif
+  0, /*nb_remainder*/
+  0, /*nb_divmod*/
+  0, /*nb_power*/
+  0, /*nb_negative*/
+  0, /*nb_positive*/
+  0, /*nb_absolute*/
+  0, /*nb_nonzero*/
+  0, /*nb_invert*/
+  0, /*nb_lshift*/
+  0, /*nb_rshift*/
+  0, /*nb_and*/
+  0, /*nb_xor*/
+  0, /*nb_or*/
+  #if PY_MAJOR_VERSION < 3
+  0, /*nb_coerce*/
+  #endif
+  0, /*nb_int*/
+  #if PY_MAJOR_VERSION < 3
+  0, /*nb_long*/
+  #else
+  0, /*reserved*/
+  #endif
+  0, /*nb_float*/
+  #if PY_MAJOR_VERSION < 3
+  0, /*nb_oct*/
+  #endif
+  #if PY_MAJOR_VERSION < 3
+  0, /*nb_hex*/
+  #endif
+  0, /*nb_inplace_add*/
+  0, /*nb_inplace_subtract*/
+  0, /*nb_inplace_multiply*/
+  #if PY_MAJOR_VERSION < 3
+  0, /*nb_inplace_divide*/
+  #endif
+  0, /*nb_inplace_remainder*/
+  0, /*nb_inplace_power*/
+  0, /*nb_inplace_lshift*/
+  0, /*nb_inplace_rshift*/
+  0, /*nb_inplace_and*/
+  0, /*nb_inplace_xor*/
+  0, /*nb_inplace_or*/
+  0, /*nb_floor_divide*/
+  0, /*nb_true_divide*/
+  0, /*nb_inplace_floor_divide*/
+  0, /*nb_inplace_true_divide*/
+  #if PY_VERSION_HEX >= 0x02050000
+  0, /*nb_index*/
+  #endif
+};
+
+static PySequenceMethods __pyx_tp_as_sequence_CandidateSet = {
+  __pyx_pw_5_cdec_12CandidateSet_5__len__, /*sq_length*/
+  0, /*sq_concat*/
+  0, /*sq_repeat*/
+  __pyx_sq_item_5_cdec_CandidateSet, /*sq_item*/
+  0, /*sq_slice*/
+  0, /*sq_ass_item*/
+  0, /*sq_ass_slice*/
+  0, /*sq_contains*/
+  0, /*sq_inplace_concat*/
+  0, /*sq_inplace_repeat*/
+};
+
+static PyMappingMethods __pyx_tp_as_mapping_CandidateSet = {
+  __pyx_pw_5_cdec_12CandidateSet_5__len__, /*mp_length*/
+  __pyx_pw_5_cdec_12CandidateSet_7__getitem__, /*mp_subscript*/
+  0, /*mp_ass_subscript*/
+};
+
+static PyBufferProcs __pyx_tp_as_buffer_CandidateSet = {
+  #if PY_MAJOR_VERSION < 3
+  0, /*bf_getreadbuffer*/
+  #endif
+  #if PY_MAJOR_VERSION < 3
+  0, /*bf_getwritebuffer*/
+  #endif
+  #if PY_MAJOR_VERSION < 3
+  0, /*bf_getsegcount*/
+  #endif
+  #if PY_MAJOR_VERSION < 3
+  0, /*bf_getcharbuffer*/
+  #endif
+  #if PY_VERSION_HEX >= 0x02060000
+  0, /*bf_getbuffer*/
+  #endif
+  #if PY_VERSION_HEX >= 0x02060000
+  0, /*bf_releasebuffer*/
+  #endif
+};
+
+static PyTypeObject __pyx_type_5_cdec_CandidateSet = {
+  PyVarObject_HEAD_INIT(0, 0)
+  __Pyx_NAMESTR("_cdec.CandidateSet"), /*tp_name*/
+  sizeof(struct __pyx_obj_5_cdec_CandidateSet), /*tp_basicsize*/
+  0, /*tp_itemsize*/
+  __pyx_tp_dealloc_5_cdec_CandidateSet, /*tp_dealloc*/
+  0, /*tp_print*/
+  0, /*tp_getattr*/
+  0, /*tp_setattr*/
+  #if PY_MAJOR_VERSION < 3
+  0, /*tp_compare*/
+  #else
+  0, /*reserved*/
+  #endif
+  0, /*tp_repr*/
+  &__pyx_tp_as_number_CandidateSet, /*tp_as_number*/
+  &__pyx_tp_as_sequence_CandidateSet, /*tp_as_sequence*/
+  &__pyx_tp_as_mapping_CandidateSet, /*tp_as_mapping*/
+  0, /*tp_hash*/
+  0, /*tp_call*/
+  0, /*tp_str*/
+  0, /*tp_getattro*/
+  0, /*tp_setattro*/
+  &__pyx_tp_as_buffer_CandidateSet, /*tp_as_buffer*/
+  Py_TPFLAGS_DEFAULT|Py_TPFLAGS_CHECKTYPES|Py_TPFLAGS_HAVE_NEWBUFFER|Py_TPFLAGS_BASETYPE, /*tp_flags*/
+  0, /*tp_doc*/
+  0, /*tp_traverse*/
+  0, /*tp_clear*/
+  0, /*tp_richcompare*/
+  0, /*tp_weaklistoffset*/
+  __pyx_pw_5_cdec_12CandidateSet_9__iter__, /*tp_iter*/
+  0, /*tp_iternext*/
+  __pyx_methods_5_cdec_CandidateSet, /*tp_methods*/
+  0, /*tp_members*/
+  0, /*tp_getset*/
+  0, /*tp_base*/
+  0, /*tp_dict*/
+  0, /*tp_descr_get*/
+  0, /*tp_descr_set*/
+  0, /*tp_dictoffset*/
+  0, /*tp_init*/
+  0, /*tp_alloc*/
+  __pyx_tp_new_5_cdec_CandidateSet, /*tp_new*/
+  0, /*tp_free*/
+  0, /*tp_is_gc*/
+  0, /*tp_bases*/
+  0, /*tp_mro*/
+  0, /*tp_cache*/
+  0, /*tp_subclasses*/
+  0, /*tp_weaklist*/
+  0, /*tp_del*/
+  #if PY_VERSION_HEX >= 0x02060000
+  0, /*tp_version_tag*/
+  #endif
+};
+
+static PyObject *__pyx_tp_new_5_cdec_SegmentEvaluator(PyTypeObject *t, PyObject *a, PyObject *k) {
+  PyObject *o = (*t->tp_alloc)(t, 0);
+  if (!o) return 0;
+  return o;
+}
+
+static void __pyx_tp_dealloc_5_cdec_SegmentEvaluator(PyObject *o) {
+  {
+    PyObject *etype, *eval, *etb;
+    PyErr_Fetch(&etype, &eval, &etb);
+    ++Py_REFCNT(o);
+    __pyx_pw_5_cdec_16SegmentEvaluator_1__dealloc__(o);
+    if (PyErr_Occurred()) PyErr_WriteUnraisable(o);
+    --Py_REFCNT(o);
+    PyErr_Restore(etype, eval, etb);
+  }
+  (*Py_TYPE(o)->tp_free)(o);
+}
+
+static PyMethodDef __pyx_methods_5_cdec_SegmentEvaluator[] = {
+  {__Pyx_NAMESTR("evaluate"), (PyCFunction)__pyx_pw_5_cdec_16SegmentEvaluator_3evaluate, METH_O, __Pyx_DOCSTR(0)},
+  {__Pyx_NAMESTR("candidate_set"), (PyCFunction)__pyx_pw_5_cdec_16SegmentEvaluator_5candidate_set, METH_NOARGS, __Pyx_DOCSTR(0)},
+  {0, 0, 0, 0}
+};
+
+static PyNumberMethods __pyx_tp_as_number_SegmentEvaluator = {
+  0, /*nb_add*/
+  0, /*nb_subtract*/
+  0, /*nb_multiply*/
+  #if PY_MAJOR_VERSION < 3
+  0, /*nb_divide*/
+  #endif
+  0, /*nb_remainder*/
+  0, /*nb_divmod*/
+  0, /*nb_power*/
+  0, /*nb_negative*/
+  0, /*nb_positive*/
+  0, /*nb_absolute*/
+  0, /*nb_nonzero*/
+  0, /*nb_invert*/
+  0, /*nb_lshift*/
+  0, /*nb_rshift*/
+  0, /*nb_and*/
+  0, /*nb_xor*/
+  0, /*nb_or*/
+  #if PY_MAJOR_VERSION < 3
+  0, /*nb_coerce*/
+  #endif
+  0, /*nb_int*/
+  #if PY_MAJOR_VERSION < 3
+  0, /*nb_long*/
+  #else
+  0, /*reserved*/
+  #endif
+  0, /*nb_float*/
+  #if PY_MAJOR_VERSION < 3
+  0, /*nb_oct*/
+  #endif
+  #if PY_MAJOR_VERSION < 3
+  0, /*nb_hex*/
+  #endif
+  0, /*nb_inplace_add*/
+  0, /*nb_inplace_subtract*/
+  0, /*nb_inplace_multiply*/
+  #if PY_MAJOR_VERSION < 3
+  0, /*nb_inplace_divide*/
+  #endif
+  0, /*nb_inplace_remainder*/
+  0, /*nb_inplace_power*/
+  0, /*nb_inplace_lshift*/
+  0, /*nb_inplace_rshift*/
+  0, /*nb_inplace_and*/
+  0, /*nb_inplace_xor*/
+  0, /*nb_inplace_or*/
+  0, /*nb_floor_divide*/
+  0, /*nb_true_divide*/
+  0, /*nb_inplace_floor_divide*/
+  0, /*nb_inplace_true_divide*/
+  #if PY_VERSION_HEX >= 0x02050000
+  0, /*nb_index*/
+  #endif
+};
+
+static PySequenceMethods __pyx_tp_as_sequence_SegmentEvaluator = {
+  0, /*sq_length*/
+  0, /*sq_concat*/
+  0, /*sq_repeat*/
+  0, /*sq_item*/
+  0, /*sq_slice*/
+  0, /*sq_ass_item*/
+  0, /*sq_ass_slice*/
+  0, /*sq_contains*/
+  0, /*sq_inplace_concat*/
+  0, /*sq_inplace_repeat*/
+};
+
+static PyMappingMethods __pyx_tp_as_mapping_SegmentEvaluator = {
+  0, /*mp_length*/
+  0, /*mp_subscript*/
+  0, /*mp_ass_subscript*/
+};
+
+static PyBufferProcs __pyx_tp_as_buffer_SegmentEvaluator = {
+  #if PY_MAJOR_VERSION < 3
+  0, /*bf_getreadbuffer*/
+  #endif
+  #if PY_MAJOR_VERSION < 3
+  0, /*bf_getwritebuffer*/
+  #endif
+  #if PY_MAJOR_VERSION < 3
+  0, /*bf_getsegcount*/
+  #endif
+  #if PY_MAJOR_VERSION < 3
+  0, /*bf_getcharbuffer*/
+  #endif
+  #if PY_VERSION_HEX >= 0x02060000
+  0, /*bf_getbuffer*/
+  #endif
+  #if PY_VERSION_HEX >= 0x02060000
+  0, /*bf_releasebuffer*/
+  #endif
+};
+
+static PyTypeObject __pyx_type_5_cdec_SegmentEvaluator = {
+  PyVarObject_HEAD_INIT(0, 0)
+  __Pyx_NAMESTR("_cdec.SegmentEvaluator"), /*tp_name*/
+  sizeof(struct __pyx_obj_5_cdec_SegmentEvaluator), /*tp_basicsize*/
+  0, /*tp_itemsize*/
+  __pyx_tp_dealloc_5_cdec_SegmentEvaluator, /*tp_dealloc*/
+  0, /*tp_print*/
+  0, /*tp_getattr*/
+  0, /*tp_setattr*/
+  #if PY_MAJOR_VERSION < 3
+  0, /*tp_compare*/
+  #else
+  0, /*reserved*/
+  #endif
+  0, /*tp_repr*/
+  &__pyx_tp_as_number_SegmentEvaluator, /*tp_as_number*/
+  &__pyx_tp_as_sequence_SegmentEvaluator, /*tp_as_sequence*/
+  &__pyx_tp_as_mapping_SegmentEvaluator, /*tp_as_mapping*/
+  0, /*tp_hash*/
+  0, /*tp_call*/
+  0, /*tp_str*/
+  0, /*tp_getattro*/
+  0, /*tp_setattro*/
+  &__pyx_tp_as_buffer_SegmentEvaluator, /*tp_as_buffer*/
+  Py_TPFLAGS_DEFAULT|Py_TPFLAGS_CHECKTYPES|Py_TPFLAGS_HAVE_NEWBUFFER|Py_TPFLAGS_BASETYPE, /*tp_flags*/
+  0, /*tp_doc*/
+  0, /*tp_traverse*/
+  0, /*tp_clear*/
+  0, /*tp_richcompare*/
+  0, /*tp_weaklistoffset*/
+  0, /*tp_iter*/
+  0, /*tp_iternext*/
+  __pyx_methods_5_cdec_SegmentEvaluator, /*tp_methods*/
+  0, /*tp_members*/
+  0, /*tp_getset*/
+  0, /*tp_base*/
+  0, /*tp_dict*/
+  0, /*tp_descr_get*/
+  0, /*tp_descr_set*/
+  0, /*tp_dictoffset*/
+  0, /*tp_init*/
+  0, /*tp_alloc*/
+  __pyx_tp_new_5_cdec_SegmentEvaluator, /*tp_new*/
+  0, /*tp_free*/
+  0, /*tp_is_gc*/
+  0, /*tp_bases*/
+  0, /*tp_mro*/
+  0, /*tp_cache*/
+  0, /*tp_subclasses*/
+  0, /*tp_weaklist*/
+  0, /*tp_del*/
+  #if PY_VERSION_HEX >= 0x02060000
+  0, /*tp_version_tag*/
+  #endif
+};
+
+static PyObject *__pyx_tp_new_5_cdec_Scorer(PyTypeObject *t, PyObject *a, PyObject *k) {
+  PyObject *o = (*t->tp_alloc)(t, 0);
+  if (!o) return 0;
+  if (__pyx_pw_5_cdec_6Scorer_1__cinit__(o, a, k) < 0) {
+    Py_DECREF(o); o = 0;
+  }
+  return o;
+}
+
+static void __pyx_tp_dealloc_5_cdec_Scorer(PyObject *o) {
+  {
+    PyObject *etype, *eval, *etb;
+    PyErr_Fetch(&etype, &eval, &etb);
+    ++Py_REFCNT(o);
+    __pyx_pw_5_cdec_6Scorer_3__dealloc__(o);
+    if (PyErr_Occurred()) PyErr_WriteUnraisable(o);
+    --Py_REFCNT(o);
+    PyErr_Restore(etype, eval, etb);
+  }
+  (*Py_TYPE(o)->tp_free)(o);
+}
+
+static PyMethodDef __pyx_methods_5_cdec_Scorer[] = {
+  {0, 0, 0, 0}
+};
+
+static PyNumberMethods __pyx_tp_as_number_Scorer = {
+  0, /*nb_add*/
+  0, /*nb_subtract*/
+  0, /*nb_multiply*/
+  #if PY_MAJOR_VERSION < 3
+  0, /*nb_divide*/
+  #endif
+  0, /*nb_remainder*/
+  0, /*nb_divmod*/
+  0, /*nb_power*/
+  0, /*nb_negative*/
+  0, /*nb_positive*/
+  0, /*nb_absolute*/
+  0, /*nb_nonzero*/
+  0, /*nb_invert*/
+  0, /*nb_lshift*/
+  0, /*nb_rshift*/
+  0, /*nb_and*/
+  0, /*nb_xor*/
+  0, /*nb_or*/
+  #if PY_MAJOR_VERSION < 3
+  0, /*nb_coerce*/
+  #endif
+  0, /*nb_int*/
+  #if PY_MAJOR_VERSION < 3
+  0, /*nb_long*/
+  #else
+  0, /*reserved*/
+  #endif
+  0, /*nb_float*/
+  #if PY_MAJOR_VERSION < 3
+  0, /*nb_oct*/
+  #endif
+  #if PY_MAJOR_VERSION < 3
+  0, /*nb_hex*/
+  #endif
+  0, /*nb_inplace_add*/
+  0, /*nb_inplace_subtract*/
+  0, /*nb_inplace_multiply*/
+  #if PY_MAJOR_VERSION < 3
+  0, /*nb_inplace_divide*/
+  #endif
+  0, /*nb_inplace_remainder*/
+  0, /*nb_inplace_power*/
+  0, /*nb_inplace_lshift*/
+  0, /*nb_inplace_rshift*/
+  0, /*nb_inplace_and*/
+  0, /*nb_inplace_xor*/
+  0, /*nb_inplace_or*/
+  0, /*nb_floor_divide*/
+  0, /*nb_true_divide*/
+  0, /*nb_inplace_floor_divide*/
+  0, /*nb_inplace_true_divide*/
+  #if PY_VERSION_HEX >= 0x02050000
+  0, /*nb_index*/
+  #endif
+};
+
+static PySequenceMethods __pyx_tp_as_sequence_Scorer = {
+  0, /*sq_length*/
+  0, /*sq_concat*/
+  0, /*sq_repeat*/
+  0, /*sq_item*/
+  0, /*sq_slice*/
+  0, /*sq_ass_item*/
+  0, /*sq_ass_slice*/
+  0, /*sq_contains*/
+  0, /*sq_inplace_concat*/
+  0, /*sq_inplace_repeat*/
+};
+
+static PyMappingMethods __pyx_tp_as_mapping_Scorer = {
+  0, /*mp_length*/
+  0, /*mp_subscript*/
+  0, /*mp_ass_subscript*/
+};
+
+static PyBufferProcs __pyx_tp_as_buffer_Scorer = {
+  #if PY_MAJOR_VERSION < 3
+  0, /*bf_getreadbuffer*/
+  #endif
+  #if PY_MAJOR_VERSION < 3
+  0, /*bf_getwritebuffer*/
+  #endif
+  #if PY_MAJOR_VERSION < 3
+  0, /*bf_getsegcount*/
+  #endif
+  #if PY_MAJOR_VERSION < 3
+  0, /*bf_getcharbuffer*/
+  #endif
+  #if PY_VERSION_HEX >= 0x02060000
+  0, /*bf_getbuffer*/
+  #endif
+  #if PY_VERSION_HEX >= 0x02060000
+  0, /*bf_releasebuffer*/
+  #endif
+};
+
+static PyTypeObject __pyx_type_5_cdec_Scorer = {
+  PyVarObject_HEAD_INIT(0, 0)
+  __Pyx_NAMESTR("_cdec.Scorer"), /*tp_name*/
+  sizeof(struct __pyx_obj_5_cdec_Scorer), /*tp_basicsize*/
+  0, /*tp_itemsize*/
+  __pyx_tp_dealloc_5_cdec_Scorer, /*tp_dealloc*/
+  0, /*tp_print*/
+  0, /*tp_getattr*/
+  0, /*tp_setattr*/
+  #if PY_MAJOR_VERSION < 3
+  0, /*tp_compare*/
+  #else
+  0, /*reserved*/
+  #endif
+  0, /*tp_repr*/
+  &__pyx_tp_as_number_Scorer, /*tp_as_number*/
+  &__pyx_tp_as_sequence_Scorer, /*tp_as_sequence*/
+  &__pyx_tp_as_mapping_Scorer, /*tp_as_mapping*/
+  0, /*tp_hash*/
+  __pyx_pw_5_cdec_6Scorer_5__call__, /*tp_call*/
+  __pyx_pw_5_cdec_6Scorer_7__str__, /*tp_str*/
+  0, /*tp_getattro*/
+  0, /*tp_setattro*/
+  &__pyx_tp_as_buffer_Scorer, /*tp_as_buffer*/
+  Py_TPFLAGS_DEFAULT|Py_TPFLAGS_CHECKTYPES|Py_TPFLAGS_HAVE_NEWBUFFER|Py_TPFLAGS_BASETYPE, /*tp_flags*/
+  0, /*tp_doc*/
+  0, /*tp_traverse*/
+  0, /*tp_clear*/
+  0, /*tp_richcompare*/
+  0, /*tp_weaklistoffset*/
+  0, /*tp_iter*/
+  0, /*tp_iternext*/
+  __pyx_methods_5_cdec_Scorer, /*tp_methods*/
+  0, /*tp_members*/
+  0, /*tp_getset*/
+  0, /*tp_base*/
+  0, /*tp_dict*/
+  0, /*tp_descr_get*/
+  0, /*tp_descr_set*/
+  0, /*tp_dictoffset*/
+  0, /*tp_init*/
+  0, /*tp_alloc*/
+  __pyx_tp_new_5_cdec_Scorer, /*tp_new*/
+  0, /*tp_free*/
+  0, /*tp_is_gc*/
+  0, /*tp_bases*/
+  0, /*tp_mro*/
+  0, /*tp_cache*/
+  0, /*tp_subclasses*/
+  0, /*tp_weaklist*/
+  0, /*tp_del*/
+  #if PY_VERSION_HEX >= 0x02060000
+  0, /*tp_version_tag*/
+  #endif
+};
+
 static PyObject *__pyx_tp_new_5_cdec_Decoder(PyTypeObject *t, PyObject *a, PyObject *k) {
   struct __pyx_obj_5_cdec_Decoder *p;
   PyObject *o = (*t->tp_alloc)(t, 0);
@@ -7017,14 +10952,12 @@ static PyObject *__pyx_tp_new_5_cdec___pyx_scope_struct_1___iter__(PyTypeObject
   PyObject *o = (*t->tp_alloc)(t, 0);
   if (!o) return 0;
   p = ((struct __pyx_obj_5_cdec___pyx_scope_struct_1___iter__ *)o);
-  p->__pyx_v_fname = 0;
   p->__pyx_v_self = 0;
   return o;
 }
 
 static void __pyx_tp_dealloc_5_cdec___pyx_scope_struct_1___iter__(PyObject *o) {
   struct __pyx_obj_5_cdec___pyx_scope_struct_1___iter__ *p = (struct __pyx_obj_5_cdec___pyx_scope_struct_1___iter__ *)o;
-  Py_XDECREF(((PyObject *)p->__pyx_v_fname));
   Py_XDECREF(((PyObject *)p->__pyx_v_self));
   (*Py_TYPE(o)->tp_free)(o);
 }
@@ -7032,9 +10965,6 @@ static void __pyx_tp_dealloc_5_cdec___pyx_scope_struct_1___iter__(PyObject *o) {
 static int __pyx_tp_traverse_5_cdec___pyx_scope_struct_1___iter__(PyObject *o, visitproc v, void *a) {
   int e;
   struct __pyx_obj_5_cdec___pyx_scope_struct_1___iter__ *p = (struct __pyx_obj_5_cdec___pyx_scope_struct_1___iter__ *)o;
-  if (p->__pyx_v_fname) {
-    e = (*v)(p->__pyx_v_fname, a); if (e) return e;
-  }
   if (p->__pyx_v_self) {
     e = (*v)(((PyObject*)p->__pyx_v_self), a); if (e) return e;
   }
@@ -7044,9 +10974,6 @@ static int __pyx_tp_traverse_5_cdec___pyx_scope_struct_1___iter__(PyObject *o, v
 static int __pyx_tp_clear_5_cdec___pyx_scope_struct_1___iter__(PyObject *o) {
   struct __pyx_obj_5_cdec___pyx_scope_struct_1___iter__ *p = (struct __pyx_obj_5_cdec___pyx_scope_struct_1___iter__ *)o;
   PyObject* tmp;
-  tmp = ((PyObject*)p->__pyx_v_fname);
-  p->__pyx_v_fname = ((PyObject*)Py_None); Py_INCREF(Py_None);
-  Py_XDECREF(tmp);
   tmp = ((PyObject*)p->__pyx_v_self);
   p->__pyx_v_self = ((struct __pyx_obj_5_cdec_SparseVector *)Py_None); Py_INCREF(Py_None);
   Py_XDECREF(tmp);
@@ -7625,26 +11552,233 @@ static PyTypeObject __pyx_type_5_cdec___pyx_scope_struct_3_kbest_tree = {
   #endif
 };
 
-static PyObject *__pyx_tp_new_5_cdec___pyx_scope_struct_4_sample(PyTypeObject *t, PyObject *a, PyObject *k) {
-  struct __pyx_obj_5_cdec___pyx_scope_struct_4_sample *p;
+static PyObject *__pyx_tp_new_5_cdec___pyx_scope_struct_4_kbest_features(PyTypeObject *t, PyObject *a, PyObject *k) {
+  struct __pyx_obj_5_cdec___pyx_scope_struct_4_kbest_features *p;
   PyObject *o = (*t->tp_alloc)(t, 0);
   if (!o) return 0;
-  p = ((struct __pyx_obj_5_cdec___pyx_scope_struct_4_sample *)o);
+  p = ((struct __pyx_obj_5_cdec___pyx_scope_struct_4_kbest_features *)o);
+  p->__pyx_v_fmap = 0;
+  p->__pyx_v_self = 0;
+  p->__pyx_v_size = 0;
+  return o;
+}
+
+static void __pyx_tp_dealloc_5_cdec___pyx_scope_struct_4_kbest_features(PyObject *o) {
+  struct __pyx_obj_5_cdec___pyx_scope_struct_4_kbest_features *p = (struct __pyx_obj_5_cdec___pyx_scope_struct_4_kbest_features *)o;
+  Py_XDECREF(((PyObject *)p->__pyx_v_fmap));
+  Py_XDECREF(((PyObject *)p->__pyx_v_self));
+  Py_XDECREF(p->__pyx_v_size);
+  (*Py_TYPE(o)->tp_free)(o);
+}
+
+static int __pyx_tp_traverse_5_cdec___pyx_scope_struct_4_kbest_features(PyObject *o, visitproc v, void *a) {
+  int e;
+  struct __pyx_obj_5_cdec___pyx_scope_struct_4_kbest_features *p = (struct __pyx_obj_5_cdec___pyx_scope_struct_4_kbest_features *)o;
+  if (p->__pyx_v_fmap) {
+    e = (*v)(((PyObject*)p->__pyx_v_fmap), a); if (e) return e;
+  }
+  if (p->__pyx_v_self) {
+    e = (*v)(((PyObject*)p->__pyx_v_self), a); if (e) return e;
+  }
+  if (p->__pyx_v_size) {
+    e = (*v)(p->__pyx_v_size, a); if (e) return e;
+  }
+  return 0;
+}
+
+static int __pyx_tp_clear_5_cdec___pyx_scope_struct_4_kbest_features(PyObject *o) {
+  struct __pyx_obj_5_cdec___pyx_scope_struct_4_kbest_features *p = (struct __pyx_obj_5_cdec___pyx_scope_struct_4_kbest_features *)o;
+  PyObject* tmp;
+  tmp = ((PyObject*)p->__pyx_v_fmap);
+  p->__pyx_v_fmap = ((struct __pyx_obj_5_cdec_SparseVector *)Py_None); Py_INCREF(Py_None);
+  Py_XDECREF(tmp);
+  tmp = ((PyObject*)p->__pyx_v_self);
+  p->__pyx_v_self = ((struct __pyx_obj_5_cdec_Hypergraph *)Py_None); Py_INCREF(Py_None);
+  Py_XDECREF(tmp);
+  tmp = ((PyObject*)p->__pyx_v_size);
+  p->__pyx_v_size = Py_None; Py_INCREF(Py_None);
+  Py_XDECREF(tmp);
+  return 0;
+}
+
+static PyMethodDef __pyx_methods_5_cdec___pyx_scope_struct_4_kbest_features[] = {
+  {0, 0, 0, 0}
+};
+
+static PyNumberMethods __pyx_tp_as_number___pyx_scope_struct_4_kbest_features = {
+  0, /*nb_add*/
+  0, /*nb_subtract*/
+  0, /*nb_multiply*/
+  #if PY_MAJOR_VERSION < 3
+  0, /*nb_divide*/
+  #endif
+  0, /*nb_remainder*/
+  0, /*nb_divmod*/
+  0, /*nb_power*/
+  0, /*nb_negative*/
+  0, /*nb_positive*/
+  0, /*nb_absolute*/
+  0, /*nb_nonzero*/
+  0, /*nb_invert*/
+  0, /*nb_lshift*/
+  0, /*nb_rshift*/
+  0, /*nb_and*/
+  0, /*nb_xor*/
+  0, /*nb_or*/
+  #if PY_MAJOR_VERSION < 3
+  0, /*nb_coerce*/
+  #endif
+  0, /*nb_int*/
+  #if PY_MAJOR_VERSION < 3
+  0, /*nb_long*/
+  #else
+  0, /*reserved*/
+  #endif
+  0, /*nb_float*/
+  #if PY_MAJOR_VERSION < 3
+  0, /*nb_oct*/
+  #endif
+  #if PY_MAJOR_VERSION < 3
+  0, /*nb_hex*/
+  #endif
+  0, /*nb_inplace_add*/
+  0, /*nb_inplace_subtract*/
+  0, /*nb_inplace_multiply*/
+  #if PY_MAJOR_VERSION < 3
+  0, /*nb_inplace_divide*/
+  #endif
+  0, /*nb_inplace_remainder*/
+  0, /*nb_inplace_power*/
+  0, /*nb_inplace_lshift*/
+  0, /*nb_inplace_rshift*/
+  0, /*nb_inplace_and*/
+  0, /*nb_inplace_xor*/
+  0, /*nb_inplace_or*/
+  0, /*nb_floor_divide*/
+  0, /*nb_true_divide*/
+  0, /*nb_inplace_floor_divide*/
+  0, /*nb_inplace_true_divide*/
+  #if PY_VERSION_HEX >= 0x02050000
+  0, /*nb_index*/
+  #endif
+};
+
+static PySequenceMethods __pyx_tp_as_sequence___pyx_scope_struct_4_kbest_features = {
+  0, /*sq_length*/
+  0, /*sq_concat*/
+  0, /*sq_repeat*/
+  0, /*sq_item*/
+  0, /*sq_slice*/
+  0, /*sq_ass_item*/
+  0, /*sq_ass_slice*/
+  0, /*sq_contains*/
+  0, /*sq_inplace_concat*/
+  0, /*sq_inplace_repeat*/
+};
+
+static PyMappingMethods __pyx_tp_as_mapping___pyx_scope_struct_4_kbest_features = {
+  0, /*mp_length*/
+  0, /*mp_subscript*/
+  0, /*mp_ass_subscript*/
+};
+
+static PyBufferProcs __pyx_tp_as_buffer___pyx_scope_struct_4_kbest_features = {
+  #if PY_MAJOR_VERSION < 3
+  0, /*bf_getreadbuffer*/
+  #endif
+  #if PY_MAJOR_VERSION < 3
+  0, /*bf_getwritebuffer*/
+  #endif
+  #if PY_MAJOR_VERSION < 3
+  0, /*bf_getsegcount*/
+  #endif
+  #if PY_MAJOR_VERSION < 3
+  0, /*bf_getcharbuffer*/
+  #endif
+  #if PY_VERSION_HEX >= 0x02060000
+  0, /*bf_getbuffer*/
+  #endif
+  #if PY_VERSION_HEX >= 0x02060000
+  0, /*bf_releasebuffer*/
+  #endif
+};
+
+static PyTypeObject __pyx_type_5_cdec___pyx_scope_struct_4_kbest_features = {
+  PyVarObject_HEAD_INIT(0, 0)
+  __Pyx_NAMESTR("_cdec.__pyx_scope_struct_4_kbest_features"), /*tp_name*/
+  sizeof(struct __pyx_obj_5_cdec___pyx_scope_struct_4_kbest_features), /*tp_basicsize*/
+  0, /*tp_itemsize*/
+  __pyx_tp_dealloc_5_cdec___pyx_scope_struct_4_kbest_features, /*tp_dealloc*/
+  0, /*tp_print*/
+  0, /*tp_getattr*/
+  0, /*tp_setattr*/
+  #if PY_MAJOR_VERSION < 3
+  0, /*tp_compare*/
+  #else
+  0, /*reserved*/
+  #endif
+  0, /*tp_repr*/
+  &__pyx_tp_as_number___pyx_scope_struct_4_kbest_features, /*tp_as_number*/
+  &__pyx_tp_as_sequence___pyx_scope_struct_4_kbest_features, /*tp_as_sequence*/
+  &__pyx_tp_as_mapping___pyx_scope_struct_4_kbest_features, /*tp_as_mapping*/
+  0, /*tp_hash*/
+  0, /*tp_call*/
+  0, /*tp_str*/
+  0, /*tp_getattro*/
+  0, /*tp_setattro*/
+  &__pyx_tp_as_buffer___pyx_scope_struct_4_kbest_features, /*tp_as_buffer*/
+  Py_TPFLAGS_DEFAULT|Py_TPFLAGS_CHECKTYPES|Py_TPFLAGS_HAVE_NEWBUFFER|Py_TPFLAGS_HAVE_GC, /*tp_flags*/
+  0, /*tp_doc*/
+  __pyx_tp_traverse_5_cdec___pyx_scope_struct_4_kbest_features, /*tp_traverse*/
+  __pyx_tp_clear_5_cdec___pyx_scope_struct_4_kbest_features, /*tp_clear*/
+  0, /*tp_richcompare*/
+  0, /*tp_weaklistoffset*/
+  0, /*tp_iter*/
+  0, /*tp_iternext*/
+  __pyx_methods_5_cdec___pyx_scope_struct_4_kbest_features, /*tp_methods*/
+  0, /*tp_members*/
+  0, /*tp_getset*/
+  0, /*tp_base*/
+  0, /*tp_dict*/
+  0, /*tp_descr_get*/
+  0, /*tp_descr_set*/
+  0, /*tp_dictoffset*/
+  0, /*tp_init*/
+  0, /*tp_alloc*/
+  __pyx_tp_new_5_cdec___pyx_scope_struct_4_kbest_features, /*tp_new*/
+  0, /*tp_free*/
+  0, /*tp_is_gc*/
+  0, /*tp_bases*/
+  0, /*tp_mro*/
+  0, /*tp_cache*/
+  0, /*tp_subclasses*/
+  0, /*tp_weaklist*/
+  0, /*tp_del*/
+  #if PY_VERSION_HEX >= 0x02060000
+  0, /*tp_version_tag*/
+  #endif
+};
+
+static PyObject *__pyx_tp_new_5_cdec___pyx_scope_struct_5_sample(PyTypeObject *t, PyObject *a, PyObject *k) {
+  struct __pyx_obj_5_cdec___pyx_scope_struct_5_sample *p;
+  PyObject *o = (*t->tp_alloc)(t, 0);
+  if (!o) return 0;
+  p = ((struct __pyx_obj_5_cdec___pyx_scope_struct_5_sample *)o);
   p->__pyx_v_self = 0;
   p->__pyx_v_sentence = 0;
   return o;
 }
 
-static void __pyx_tp_dealloc_5_cdec___pyx_scope_struct_4_sample(PyObject *o) {
-  struct __pyx_obj_5_cdec___pyx_scope_struct_4_sample *p = (struct __pyx_obj_5_cdec___pyx_scope_struct_4_sample *)o;
+static void __pyx_tp_dealloc_5_cdec___pyx_scope_struct_5_sample(PyObject *o) {
+  struct __pyx_obj_5_cdec___pyx_scope_struct_5_sample *p = (struct __pyx_obj_5_cdec___pyx_scope_struct_5_sample *)o;
   Py_XDECREF(((PyObject *)p->__pyx_v_self));
   Py_XDECREF(((PyObject *)p->__pyx_v_sentence));
   (*Py_TYPE(o)->tp_free)(o);
 }
 
-static int __pyx_tp_traverse_5_cdec___pyx_scope_struct_4_sample(PyObject *o, visitproc v, void *a) {
+static int __pyx_tp_traverse_5_cdec___pyx_scope_struct_5_sample(PyObject *o, visitproc v, void *a) {
   int e;
-  struct __pyx_obj_5_cdec___pyx_scope_struct_4_sample *p = (struct __pyx_obj_5_cdec___pyx_scope_struct_4_sample *)o;
+  struct __pyx_obj_5_cdec___pyx_scope_struct_5_sample *p = (struct __pyx_obj_5_cdec___pyx_scope_struct_5_sample *)o;
   if (p->__pyx_v_self) {
     e = (*v)(((PyObject*)p->__pyx_v_self), a); if (e) return e;
   }
@@ -7654,8 +11788,8 @@ static int __pyx_tp_traverse_5_cdec___pyx_scope_struct_4_sample(PyObject *o, vis
   return 0;
 }
 
-static int __pyx_tp_clear_5_cdec___pyx_scope_struct_4_sample(PyObject *o) {
-  struct __pyx_obj_5_cdec___pyx_scope_struct_4_sample *p = (struct __pyx_obj_5_cdec___pyx_scope_struct_4_sample *)o;
+static int __pyx_tp_clear_5_cdec___pyx_scope_struct_5_sample(PyObject *o) {
+  struct __pyx_obj_5_cdec___pyx_scope_struct_5_sample *p = (struct __pyx_obj_5_cdec___pyx_scope_struct_5_sample *)o;
   PyObject* tmp;
   tmp = ((PyObject*)p->__pyx_v_self);
   p->__pyx_v_self = ((struct __pyx_obj_5_cdec_Hypergraph *)Py_None); Py_INCREF(Py_None);
@@ -7666,11 +11800,11 @@ static int __pyx_tp_clear_5_cdec___pyx_scope_struct_4_sample(PyObject *o) {
   return 0;
 }
 
-static PyMethodDef __pyx_methods_5_cdec___pyx_scope_struct_4_sample[] = {
+static PyMethodDef __pyx_methods_5_cdec___pyx_scope_struct_5_sample[] = {
   {0, 0, 0, 0}
 };
 
-static PyNumberMethods __pyx_tp_as_number___pyx_scope_struct_4_sample = {
+static PyNumberMethods __pyx_tp_as_number___pyx_scope_struct_5_sample = {
   0, /*nb_add*/
   0, /*nb_subtract*/
   0, /*nb_multiply*/
@@ -7728,7 +11862,7 @@ static PyNumberMethods __pyx_tp_as_number___pyx_scope_struct_4_sample = {
   #endif
 };
 
-static PySequenceMethods __pyx_tp_as_sequence___pyx_scope_struct_4_sample = {
+static PySequenceMethods __pyx_tp_as_sequence___pyx_scope_struct_5_sample = {
   0, /*sq_length*/
   0, /*sq_concat*/
   0, /*sq_repeat*/
@@ -7741,13 +11875,13 @@ static PySequenceMethods __pyx_tp_as_sequence___pyx_scope_struct_4_sample = {
   0, /*sq_inplace_repeat*/
 };
 
-static PyMappingMethods __pyx_tp_as_mapping___pyx_scope_struct_4_sample = {
+static PyMappingMethods __pyx_tp_as_mapping___pyx_scope_struct_5_sample = {
   0, /*mp_length*/
   0, /*mp_subscript*/
   0, /*mp_ass_subscript*/
 };
 
-static PyBufferProcs __pyx_tp_as_buffer___pyx_scope_struct_4_sample = {
+static PyBufferProcs __pyx_tp_as_buffer___pyx_scope_struct_5_sample = {
   #if PY_MAJOR_VERSION < 3
   0, /*bf_getreadbuffer*/
   #endif
@@ -7768,12 +11902,12 @@ static PyBufferProcs __pyx_tp_as_buffer___pyx_scope_struct_4_sample = {
   #endif
 };
 
-static PyTypeObject __pyx_type_5_cdec___pyx_scope_struct_4_sample = {
+static PyTypeObject __pyx_type_5_cdec___pyx_scope_struct_5_sample = {
   PyVarObject_HEAD_INIT(0, 0)
-  __Pyx_NAMESTR("_cdec.__pyx_scope_struct_4_sample"), /*tp_name*/
-  sizeof(struct __pyx_obj_5_cdec___pyx_scope_struct_4_sample), /*tp_basicsize*/
+  __Pyx_NAMESTR("_cdec.__pyx_scope_struct_5_sample"), /*tp_name*/
+  sizeof(struct __pyx_obj_5_cdec___pyx_scope_struct_5_sample), /*tp_basicsize*/
   0, /*tp_itemsize*/
-  __pyx_tp_dealloc_5_cdec___pyx_scope_struct_4_sample, /*tp_dealloc*/
+  __pyx_tp_dealloc_5_cdec___pyx_scope_struct_5_sample, /*tp_dealloc*/
   0, /*tp_print*/
   0, /*tp_getattr*/
   0, /*tp_setattr*/
@@ -7783,24 +11917,24 @@ static PyTypeObject __pyx_type_5_cdec___pyx_scope_struct_4_sample = {
   0, /*reserved*/
   #endif
   0, /*tp_repr*/
-  &__pyx_tp_as_number___pyx_scope_struct_4_sample, /*tp_as_number*/
-  &__pyx_tp_as_sequence___pyx_scope_struct_4_sample, /*tp_as_sequence*/
-  &__pyx_tp_as_mapping___pyx_scope_struct_4_sample, /*tp_as_mapping*/
+  &__pyx_tp_as_number___pyx_scope_struct_5_sample, /*tp_as_number*/
+  &__pyx_tp_as_sequence___pyx_scope_struct_5_sample, /*tp_as_sequence*/
+  &__pyx_tp_as_mapping___pyx_scope_struct_5_sample, /*tp_as_mapping*/
   0, /*tp_hash*/
   0, /*tp_call*/
   0, /*tp_str*/
   0, /*tp_getattro*/
   0, /*tp_setattro*/
-  &__pyx_tp_as_buffer___pyx_scope_struct_4_sample, /*tp_as_buffer*/
+  &__pyx_tp_as_buffer___pyx_scope_struct_5_sample, /*tp_as_buffer*/
   Py_TPFLAGS_DEFAULT|Py_TPFLAGS_CHECKTYPES|Py_TPFLAGS_HAVE_NEWBUFFER|Py_TPFLAGS_HAVE_GC, /*tp_flags*/
   0, /*tp_doc*/
-  __pyx_tp_traverse_5_cdec___pyx_scope_struct_4_sample, /*tp_traverse*/
-  __pyx_tp_clear_5_cdec___pyx_scope_struct_4_sample, /*tp_clear*/
+  __pyx_tp_traverse_5_cdec___pyx_scope_struct_5_sample, /*tp_traverse*/
+  __pyx_tp_clear_5_cdec___pyx_scope_struct_5_sample, /*tp_clear*/
   0, /*tp_richcompare*/
   0, /*tp_weaklistoffset*/
   0, /*tp_iter*/
   0, /*tp_iternext*/
-  __pyx_methods_5_cdec___pyx_scope_struct_4_sample, /*tp_methods*/
+  __pyx_methods_5_cdec___pyx_scope_struct_5_sample, /*tp_methods*/
   0, /*tp_members*/
   0, /*tp_getset*/
   0, /*tp_base*/
@@ -7810,7 +11944,7 @@ static PyTypeObject __pyx_type_5_cdec___pyx_scope_struct_4_sample = {
   0, /*tp_dictoffset*/
   0, /*tp_init*/
   0, /*tp_alloc*/
-  __pyx_tp_new_5_cdec___pyx_scope_struct_4_sample, /*tp_new*/
+  __pyx_tp_new_5_cdec___pyx_scope_struct_5_sample, /*tp_new*/
   0, /*tp_free*/
   0, /*tp_is_gc*/
   0, /*tp_bases*/
@@ -7824,32 +11958,32 @@ static PyTypeObject __pyx_type_5_cdec___pyx_scope_struct_4_sample = {
   #endif
 };
 
-static PyObject *__pyx_tp_new_5_cdec___pyx_scope_struct_5___iter__(PyTypeObject *t, PyObject *a, PyObject *k) {
-  struct __pyx_obj_5_cdec___pyx_scope_struct_5___iter__ *p;
+static PyObject *__pyx_tp_new_5_cdec___pyx_scope_struct_6___iter__(PyTypeObject *t, PyObject *a, PyObject *k) {
+  struct __pyx_obj_5_cdec___pyx_scope_struct_6___iter__ *p;
   PyObject *o = (*t->tp_alloc)(t, 0);
   if (!o) return 0;
-  p = ((struct __pyx_obj_5_cdec___pyx_scope_struct_5___iter__ *)o);
+  p = ((struct __pyx_obj_5_cdec___pyx_scope_struct_6___iter__ *)o);
   p->__pyx_v_self = 0;
   return o;
 }
 
-static void __pyx_tp_dealloc_5_cdec___pyx_scope_struct_5___iter__(PyObject *o) {
-  struct __pyx_obj_5_cdec___pyx_scope_struct_5___iter__ *p = (struct __pyx_obj_5_cdec___pyx_scope_struct_5___iter__ *)o;
+static void __pyx_tp_dealloc_5_cdec___pyx_scope_struct_6___iter__(PyObject *o) {
+  struct __pyx_obj_5_cdec___pyx_scope_struct_6___iter__ *p = (struct __pyx_obj_5_cdec___pyx_scope_struct_6___iter__ *)o;
   Py_XDECREF(((PyObject *)p->__pyx_v_self));
   (*Py_TYPE(o)->tp_free)(o);
 }
 
-static int __pyx_tp_traverse_5_cdec___pyx_scope_struct_5___iter__(PyObject *o, visitproc v, void *a) {
+static int __pyx_tp_traverse_5_cdec___pyx_scope_struct_6___iter__(PyObject *o, visitproc v, void *a) {
   int e;
-  struct __pyx_obj_5_cdec___pyx_scope_struct_5___iter__ *p = (struct __pyx_obj_5_cdec___pyx_scope_struct_5___iter__ *)o;
+  struct __pyx_obj_5_cdec___pyx_scope_struct_6___iter__ *p = (struct __pyx_obj_5_cdec___pyx_scope_struct_6___iter__ *)o;
   if (p->__pyx_v_self) {
     e = (*v)(((PyObject*)p->__pyx_v_self), a); if (e) return e;
   }
   return 0;
 }
 
-static int __pyx_tp_clear_5_cdec___pyx_scope_struct_5___iter__(PyObject *o) {
-  struct __pyx_obj_5_cdec___pyx_scope_struct_5___iter__ *p = (struct __pyx_obj_5_cdec___pyx_scope_struct_5___iter__ *)o;
+static int __pyx_tp_clear_5_cdec___pyx_scope_struct_6___iter__(PyObject *o) {
+  struct __pyx_obj_5_cdec___pyx_scope_struct_6___iter__ *p = (struct __pyx_obj_5_cdec___pyx_scope_struct_6___iter__ *)o;
   PyObject* tmp;
   tmp = ((PyObject*)p->__pyx_v_self);
   p->__pyx_v_self = ((struct __pyx_obj_5_cdec_Lattice *)Py_None); Py_INCREF(Py_None);
@@ -7857,11 +11991,409 @@ static int __pyx_tp_clear_5_cdec___pyx_scope_struct_5___iter__(PyObject *o) {
   return 0;
 }
 
-static PyMethodDef __pyx_methods_5_cdec___pyx_scope_struct_5___iter__[] = {
+static PyMethodDef __pyx_methods_5_cdec___pyx_scope_struct_6___iter__[] = {
+  {0, 0, 0, 0}
+};
+
+static PyNumberMethods __pyx_tp_as_number___pyx_scope_struct_6___iter__ = {
+  0, /*nb_add*/
+  0, /*nb_subtract*/
+  0, /*nb_multiply*/
+  #if PY_MAJOR_VERSION < 3
+  0, /*nb_divide*/
+  #endif
+  0, /*nb_remainder*/
+  0, /*nb_divmod*/
+  0, /*nb_power*/
+  0, /*nb_negative*/
+  0, /*nb_positive*/
+  0, /*nb_absolute*/
+  0, /*nb_nonzero*/
+  0, /*nb_invert*/
+  0, /*nb_lshift*/
+  0, /*nb_rshift*/
+  0, /*nb_and*/
+  0, /*nb_xor*/
+  0, /*nb_or*/
+  #if PY_MAJOR_VERSION < 3
+  0, /*nb_coerce*/
+  #endif
+  0, /*nb_int*/
+  #if PY_MAJOR_VERSION < 3
+  0, /*nb_long*/
+  #else
+  0, /*reserved*/
+  #endif
+  0, /*nb_float*/
+  #if PY_MAJOR_VERSION < 3
+  0, /*nb_oct*/
+  #endif
+  #if PY_MAJOR_VERSION < 3
+  0, /*nb_hex*/
+  #endif
+  0, /*nb_inplace_add*/
+  0, /*nb_inplace_subtract*/
+  0, /*nb_inplace_multiply*/
+  #if PY_MAJOR_VERSION < 3
+  0, /*nb_inplace_divide*/
+  #endif
+  0, /*nb_inplace_remainder*/
+  0, /*nb_inplace_power*/
+  0, /*nb_inplace_lshift*/
+  0, /*nb_inplace_rshift*/
+  0, /*nb_inplace_and*/
+  0, /*nb_inplace_xor*/
+  0, /*nb_inplace_or*/
+  0, /*nb_floor_divide*/
+  0, /*nb_true_divide*/
+  0, /*nb_inplace_floor_divide*/
+  0, /*nb_inplace_true_divide*/
+  #if PY_VERSION_HEX >= 0x02050000
+  0, /*nb_index*/
+  #endif
+};
+
+static PySequenceMethods __pyx_tp_as_sequence___pyx_scope_struct_6___iter__ = {
+  0, /*sq_length*/
+  0, /*sq_concat*/
+  0, /*sq_repeat*/
+  0, /*sq_item*/
+  0, /*sq_slice*/
+  0, /*sq_ass_item*/
+  0, /*sq_ass_slice*/
+  0, /*sq_contains*/
+  0, /*sq_inplace_concat*/
+  0, /*sq_inplace_repeat*/
+};
+
+static PyMappingMethods __pyx_tp_as_mapping___pyx_scope_struct_6___iter__ = {
+  0, /*mp_length*/
+  0, /*mp_subscript*/
+  0, /*mp_ass_subscript*/
+};
+
+static PyBufferProcs __pyx_tp_as_buffer___pyx_scope_struct_6___iter__ = {
+  #if PY_MAJOR_VERSION < 3
+  0, /*bf_getreadbuffer*/
+  #endif
+  #if PY_MAJOR_VERSION < 3
+  0, /*bf_getwritebuffer*/
+  #endif
+  #if PY_MAJOR_VERSION < 3
+  0, /*bf_getsegcount*/
+  #endif
+  #if PY_MAJOR_VERSION < 3
+  0, /*bf_getcharbuffer*/
+  #endif
+  #if PY_VERSION_HEX >= 0x02060000
+  0, /*bf_getbuffer*/
+  #endif
+  #if PY_VERSION_HEX >= 0x02060000
+  0, /*bf_releasebuffer*/
+  #endif
+};
+
+static PyTypeObject __pyx_type_5_cdec___pyx_scope_struct_6___iter__ = {
+  PyVarObject_HEAD_INIT(0, 0)
+  __Pyx_NAMESTR("_cdec.__pyx_scope_struct_6___iter__"), /*tp_name*/
+  sizeof(struct __pyx_obj_5_cdec___pyx_scope_struct_6___iter__), /*tp_basicsize*/
+  0, /*tp_itemsize*/
+  __pyx_tp_dealloc_5_cdec___pyx_scope_struct_6___iter__, /*tp_dealloc*/
+  0, /*tp_print*/
+  0, /*tp_getattr*/
+  0, /*tp_setattr*/
+  #if PY_MAJOR_VERSION < 3
+  0, /*tp_compare*/
+  #else
+  0, /*reserved*/
+  #endif
+  0, /*tp_repr*/
+  &__pyx_tp_as_number___pyx_scope_struct_6___iter__, /*tp_as_number*/
+  &__pyx_tp_as_sequence___pyx_scope_struct_6___iter__, /*tp_as_sequence*/
+  &__pyx_tp_as_mapping___pyx_scope_struct_6___iter__, /*tp_as_mapping*/
+  0, /*tp_hash*/
+  0, /*tp_call*/
+  0, /*tp_str*/
+  0, /*tp_getattro*/
+  0, /*tp_setattro*/
+  &__pyx_tp_as_buffer___pyx_scope_struct_6___iter__, /*tp_as_buffer*/
+  Py_TPFLAGS_DEFAULT|Py_TPFLAGS_CHECKTYPES|Py_TPFLAGS_HAVE_NEWBUFFER|Py_TPFLAGS_HAVE_GC, /*tp_flags*/
+  0, /*tp_doc*/
+  __pyx_tp_traverse_5_cdec___pyx_scope_struct_6___iter__, /*tp_traverse*/
+  __pyx_tp_clear_5_cdec___pyx_scope_struct_6___iter__, /*tp_clear*/
+  0, /*tp_richcompare*/
+  0, /*tp_weaklistoffset*/
+  0, /*tp_iter*/
+  0, /*tp_iternext*/
+  __pyx_methods_5_cdec___pyx_scope_struct_6___iter__, /*tp_methods*/
+  0, /*tp_members*/
+  0, /*tp_getset*/
+  0, /*tp_base*/
+  0, /*tp_dict*/
+  0, /*tp_descr_get*/
+  0, /*tp_descr_set*/
+  0, /*tp_dictoffset*/
+  0, /*tp_init*/
+  0, /*tp_alloc*/
+  __pyx_tp_new_5_cdec___pyx_scope_struct_6___iter__, /*tp_new*/
+  0, /*tp_free*/
+  0, /*tp_is_gc*/
+  0, /*tp_bases*/
+  0, /*tp_mro*/
+  0, /*tp_cache*/
+  0, /*tp_subclasses*/
+  0, /*tp_weaklist*/
+  0, /*tp_del*/
+  #if PY_VERSION_HEX >= 0x02060000
+  0, /*tp_version_tag*/
+  #endif
+};
+
+static PyObject *__pyx_tp_new_5_cdec___pyx_scope_struct_7___iter__(PyTypeObject *t, PyObject *a, PyObject *k) {
+  struct __pyx_obj_5_cdec___pyx_scope_struct_7___iter__ *p;
+  PyObject *o = (*t->tp_alloc)(t, 0);
+  if (!o) return 0;
+  p = ((struct __pyx_obj_5_cdec___pyx_scope_struct_7___iter__ *)o);
+  p->__pyx_v_i = 0;
+  p->__pyx_v_self = 0;
+  p->__pyx_t_1 = 0;
+  return o;
+}
+
+static void __pyx_tp_dealloc_5_cdec___pyx_scope_struct_7___iter__(PyObject *o) {
+  struct __pyx_obj_5_cdec___pyx_scope_struct_7___iter__ *p = (struct __pyx_obj_5_cdec___pyx_scope_struct_7___iter__ *)o;
+  Py_XDECREF(p->__pyx_v_i);
+  Py_XDECREF(((PyObject *)p->__pyx_v_self));
+  Py_XDECREF(p->__pyx_t_1);
+  (*Py_TYPE(o)->tp_free)(o);
+}
+
+static int __pyx_tp_traverse_5_cdec___pyx_scope_struct_7___iter__(PyObject *o, visitproc v, void *a) {
+  int e;
+  struct __pyx_obj_5_cdec___pyx_scope_struct_7___iter__ *p = (struct __pyx_obj_5_cdec___pyx_scope_struct_7___iter__ *)o;
+  if (p->__pyx_v_i) {
+    e = (*v)(p->__pyx_v_i, a); if (e) return e;
+  }
+  if (p->__pyx_v_self) {
+    e = (*v)(((PyObject*)p->__pyx_v_self), a); if (e) return e;
+  }
+  if (p->__pyx_t_1) {
+    e = (*v)(p->__pyx_t_1, a); if (e) return e;
+  }
+  return 0;
+}
+
+static int __pyx_tp_clear_5_cdec___pyx_scope_struct_7___iter__(PyObject *o) {
+  struct __pyx_obj_5_cdec___pyx_scope_struct_7___iter__ *p = (struct __pyx_obj_5_cdec___pyx_scope_struct_7___iter__ *)o;
+  PyObject* tmp;
+  tmp = ((PyObject*)p->__pyx_v_i);
+  p->__pyx_v_i = Py_None; Py_INCREF(Py_None);
+  Py_XDECREF(tmp);
+  tmp = ((PyObject*)p->__pyx_v_self);
+  p->__pyx_v_self = ((struct __pyx_obj_5_cdec_SufficientStats *)Py_None); Py_INCREF(Py_None);
+  Py_XDECREF(tmp);
+  tmp = ((PyObject*)p->__pyx_t_1);
+  p->__pyx_t_1 = Py_None; Py_INCREF(Py_None);
+  Py_XDECREF(tmp);
+  return 0;
+}
+
+static PyMethodDef __pyx_methods_5_cdec___pyx_scope_struct_7___iter__[] = {
+  {0, 0, 0, 0}
+};
+
+static PyNumberMethods __pyx_tp_as_number___pyx_scope_struct_7___iter__ = {
+  0, /*nb_add*/
+  0, /*nb_subtract*/
+  0, /*nb_multiply*/
+  #if PY_MAJOR_VERSION < 3
+  0, /*nb_divide*/
+  #endif
+  0, /*nb_remainder*/
+  0, /*nb_divmod*/
+  0, /*nb_power*/
+  0, /*nb_negative*/
+  0, /*nb_positive*/
+  0, /*nb_absolute*/
+  0, /*nb_nonzero*/
+  0, /*nb_invert*/
+  0, /*nb_lshift*/
+  0, /*nb_rshift*/
+  0, /*nb_and*/
+  0, /*nb_xor*/
+  0, /*nb_or*/
+  #if PY_MAJOR_VERSION < 3
+  0, /*nb_coerce*/
+  #endif
+  0, /*nb_int*/
+  #if PY_MAJOR_VERSION < 3
+  0, /*nb_long*/
+  #else
+  0, /*reserved*/
+  #endif
+  0, /*nb_float*/
+  #if PY_MAJOR_VERSION < 3
+  0, /*nb_oct*/
+  #endif
+  #if PY_MAJOR_VERSION < 3
+  0, /*nb_hex*/
+  #endif
+  0, /*nb_inplace_add*/
+  0, /*nb_inplace_subtract*/
+  0, /*nb_inplace_multiply*/
+  #if PY_MAJOR_VERSION < 3
+  0, /*nb_inplace_divide*/
+  #endif
+  0, /*nb_inplace_remainder*/
+  0, /*nb_inplace_power*/
+  0, /*nb_inplace_lshift*/
+  0, /*nb_inplace_rshift*/
+  0, /*nb_inplace_and*/
+  0, /*nb_inplace_xor*/
+  0, /*nb_inplace_or*/
+  0, /*nb_floor_divide*/
+  0, /*nb_true_divide*/
+  0, /*nb_inplace_floor_divide*/
+  0, /*nb_inplace_true_divide*/
+  #if PY_VERSION_HEX >= 0x02050000
+  0, /*nb_index*/
+  #endif
+};
+
+static PySequenceMethods __pyx_tp_as_sequence___pyx_scope_struct_7___iter__ = {
+  0, /*sq_length*/
+  0, /*sq_concat*/
+  0, /*sq_repeat*/
+  0, /*sq_item*/
+  0, /*sq_slice*/
+  0, /*sq_ass_item*/
+  0, /*sq_ass_slice*/
+  0, /*sq_contains*/
+  0, /*sq_inplace_concat*/
+  0, /*sq_inplace_repeat*/
+};
+
+static PyMappingMethods __pyx_tp_as_mapping___pyx_scope_struct_7___iter__ = {
+  0, /*mp_length*/
+  0, /*mp_subscript*/
+  0, /*mp_ass_subscript*/
+};
+
+static PyBufferProcs __pyx_tp_as_buffer___pyx_scope_struct_7___iter__ = {
+  #if PY_MAJOR_VERSION < 3
+  0, /*bf_getreadbuffer*/
+  #endif
+  #if PY_MAJOR_VERSION < 3
+  0, /*bf_getwritebuffer*/
+  #endif
+  #if PY_MAJOR_VERSION < 3
+  0, /*bf_getsegcount*/
+  #endif
+  #if PY_MAJOR_VERSION < 3
+  0, /*bf_getcharbuffer*/
+  #endif
+  #if PY_VERSION_HEX >= 0x02060000
+  0, /*bf_getbuffer*/
+  #endif
+  #if PY_VERSION_HEX >= 0x02060000
+  0, /*bf_releasebuffer*/
+  #endif
+};
+
+static PyTypeObject __pyx_type_5_cdec___pyx_scope_struct_7___iter__ = {
+  PyVarObject_HEAD_INIT(0, 0)
+  __Pyx_NAMESTR("_cdec.__pyx_scope_struct_7___iter__"), /*tp_name*/
+  sizeof(struct __pyx_obj_5_cdec___pyx_scope_struct_7___iter__), /*tp_basicsize*/
+  0, /*tp_itemsize*/
+  __pyx_tp_dealloc_5_cdec___pyx_scope_struct_7___iter__, /*tp_dealloc*/
+  0, /*tp_print*/
+  0, /*tp_getattr*/
+  0, /*tp_setattr*/
+  #if PY_MAJOR_VERSION < 3
+  0, /*tp_compare*/
+  #else
+  0, /*reserved*/
+  #endif
+  0, /*tp_repr*/
+  &__pyx_tp_as_number___pyx_scope_struct_7___iter__, /*tp_as_number*/
+  &__pyx_tp_as_sequence___pyx_scope_struct_7___iter__, /*tp_as_sequence*/
+  &__pyx_tp_as_mapping___pyx_scope_struct_7___iter__, /*tp_as_mapping*/
+  0, /*tp_hash*/
+  0, /*tp_call*/
+  0, /*tp_str*/
+  0, /*tp_getattro*/
+  0, /*tp_setattro*/
+  &__pyx_tp_as_buffer___pyx_scope_struct_7___iter__, /*tp_as_buffer*/
+  Py_TPFLAGS_DEFAULT|Py_TPFLAGS_CHECKTYPES|Py_TPFLAGS_HAVE_NEWBUFFER|Py_TPFLAGS_HAVE_GC, /*tp_flags*/
+  0, /*tp_doc*/
+  __pyx_tp_traverse_5_cdec___pyx_scope_struct_7___iter__, /*tp_traverse*/
+  __pyx_tp_clear_5_cdec___pyx_scope_struct_7___iter__, /*tp_clear*/
+  0, /*tp_richcompare*/
+  0, /*tp_weaklistoffset*/
+  0, /*tp_iter*/
+  0, /*tp_iternext*/
+  __pyx_methods_5_cdec___pyx_scope_struct_7___iter__, /*tp_methods*/
+  0, /*tp_members*/
+  0, /*tp_getset*/
+  0, /*tp_base*/
+  0, /*tp_dict*/
+  0, /*tp_descr_get*/
+  0, /*tp_descr_set*/
+  0, /*tp_dictoffset*/
+  0, /*tp_init*/
+  0, /*tp_alloc*/
+  __pyx_tp_new_5_cdec___pyx_scope_struct_7___iter__, /*tp_new*/
+  0, /*tp_free*/
+  0, /*tp_is_gc*/
+  0, /*tp_bases*/
+  0, /*tp_mro*/
+  0, /*tp_cache*/
+  0, /*tp_subclasses*/
+  0, /*tp_weaklist*/
+  0, /*tp_del*/
+  #if PY_VERSION_HEX >= 0x02060000
+  0, /*tp_version_tag*/
+  #endif
+};
+
+static PyObject *__pyx_tp_new_5_cdec___pyx_scope_struct_8___iter__(PyTypeObject *t, PyObject *a, PyObject *k) {
+  struct __pyx_obj_5_cdec___pyx_scope_struct_8___iter__ *p;
+  PyObject *o = (*t->tp_alloc)(t, 0);
+  if (!o) return 0;
+  p = ((struct __pyx_obj_5_cdec___pyx_scope_struct_8___iter__ *)o);
+  p->__pyx_v_self = 0;
+  return o;
+}
+
+static void __pyx_tp_dealloc_5_cdec___pyx_scope_struct_8___iter__(PyObject *o) {
+  struct __pyx_obj_5_cdec___pyx_scope_struct_8___iter__ *p = (struct __pyx_obj_5_cdec___pyx_scope_struct_8___iter__ *)o;
+  Py_XDECREF(((PyObject *)p->__pyx_v_self));
+  (*Py_TYPE(o)->tp_free)(o);
+}
+
+static int __pyx_tp_traverse_5_cdec___pyx_scope_struct_8___iter__(PyObject *o, visitproc v, void *a) {
+  int e;
+  struct __pyx_obj_5_cdec___pyx_scope_struct_8___iter__ *p = (struct __pyx_obj_5_cdec___pyx_scope_struct_8___iter__ *)o;
+  if (p->__pyx_v_self) {
+    e = (*v)(((PyObject*)p->__pyx_v_self), a); if (e) return e;
+  }
+  return 0;
+}
+
+static int __pyx_tp_clear_5_cdec___pyx_scope_struct_8___iter__(PyObject *o) {
+  struct __pyx_obj_5_cdec___pyx_scope_struct_8___iter__ *p = (struct __pyx_obj_5_cdec___pyx_scope_struct_8___iter__ *)o;
+  PyObject* tmp;
+  tmp = ((PyObject*)p->__pyx_v_self);
+  p->__pyx_v_self = ((struct __pyx_obj_5_cdec_CandidateSet *)Py_None); Py_INCREF(Py_None);
+  Py_XDECREF(tmp);
+  return 0;
+}
+
+static PyMethodDef __pyx_methods_5_cdec___pyx_scope_struct_8___iter__[] = {
   {0, 0, 0, 0}
 };
 
-static PyNumberMethods __pyx_tp_as_number___pyx_scope_struct_5___iter__ = {
+static PyNumberMethods __pyx_tp_as_number___pyx_scope_struct_8___iter__ = {
   0, /*nb_add*/
   0, /*nb_subtract*/
   0, /*nb_multiply*/
@@ -7919,7 +12451,7 @@ static PyNumberMethods __pyx_tp_as_number___pyx_scope_struct_5___iter__ = {
   #endif
 };
 
-static PySequenceMethods __pyx_tp_as_sequence___pyx_scope_struct_5___iter__ = {
+static PySequenceMethods __pyx_tp_as_sequence___pyx_scope_struct_8___iter__ = {
   0, /*sq_length*/
   0, /*sq_concat*/
   0, /*sq_repeat*/
@@ -7932,13 +12464,13 @@ static PySequenceMethods __pyx_tp_as_sequence___pyx_scope_struct_5___iter__ = {
   0, /*sq_inplace_repeat*/
 };
 
-static PyMappingMethods __pyx_tp_as_mapping___pyx_scope_struct_5___iter__ = {
+static PyMappingMethods __pyx_tp_as_mapping___pyx_scope_struct_8___iter__ = {
   0, /*mp_length*/
   0, /*mp_subscript*/
   0, /*mp_ass_subscript*/
 };
 
-static PyBufferProcs __pyx_tp_as_buffer___pyx_scope_struct_5___iter__ = {
+static PyBufferProcs __pyx_tp_as_buffer___pyx_scope_struct_8___iter__ = {
   #if PY_MAJOR_VERSION < 3
   0, /*bf_getreadbuffer*/
   #endif
@@ -7959,12 +12491,12 @@ static PyBufferProcs __pyx_tp_as_buffer___pyx_scope_struct_5___iter__ = {
   #endif
 };
 
-static PyTypeObject __pyx_type_5_cdec___pyx_scope_struct_5___iter__ = {
+static PyTypeObject __pyx_type_5_cdec___pyx_scope_struct_8___iter__ = {
   PyVarObject_HEAD_INIT(0, 0)
-  __Pyx_NAMESTR("_cdec.__pyx_scope_struct_5___iter__"), /*tp_name*/
-  sizeof(struct __pyx_obj_5_cdec___pyx_scope_struct_5___iter__), /*tp_basicsize*/
+  __Pyx_NAMESTR("_cdec.__pyx_scope_struct_8___iter__"), /*tp_name*/
+  sizeof(struct __pyx_obj_5_cdec___pyx_scope_struct_8___iter__), /*tp_basicsize*/
   0, /*tp_itemsize*/
-  __pyx_tp_dealloc_5_cdec___pyx_scope_struct_5___iter__, /*tp_dealloc*/
+  __pyx_tp_dealloc_5_cdec___pyx_scope_struct_8___iter__, /*tp_dealloc*/
   0, /*tp_print*/
   0, /*tp_getattr*/
   0, /*tp_setattr*/
@@ -7974,24 +12506,24 @@ static PyTypeObject __pyx_type_5_cdec___pyx_scope_struct_5___iter__ = {
   0, /*reserved*/
   #endif
   0, /*tp_repr*/
-  &__pyx_tp_as_number___pyx_scope_struct_5___iter__, /*tp_as_number*/
-  &__pyx_tp_as_sequence___pyx_scope_struct_5___iter__, /*tp_as_sequence*/
-  &__pyx_tp_as_mapping___pyx_scope_struct_5___iter__, /*tp_as_mapping*/
+  &__pyx_tp_as_number___pyx_scope_struct_8___iter__, /*tp_as_number*/
+  &__pyx_tp_as_sequence___pyx_scope_struct_8___iter__, /*tp_as_sequence*/
+  &__pyx_tp_as_mapping___pyx_scope_struct_8___iter__, /*tp_as_mapping*/
   0, /*tp_hash*/
   0, /*tp_call*/
   0, /*tp_str*/
   0, /*tp_getattro*/
   0, /*tp_setattro*/
-  &__pyx_tp_as_buffer___pyx_scope_struct_5___iter__, /*tp_as_buffer*/
+  &__pyx_tp_as_buffer___pyx_scope_struct_8___iter__, /*tp_as_buffer*/
   Py_TPFLAGS_DEFAULT|Py_TPFLAGS_CHECKTYPES|Py_TPFLAGS_HAVE_NEWBUFFER|Py_TPFLAGS_HAVE_GC, /*tp_flags*/
   0, /*tp_doc*/
-  __pyx_tp_traverse_5_cdec___pyx_scope_struct_5___iter__, /*tp_traverse*/
-  __pyx_tp_clear_5_cdec___pyx_scope_struct_5___iter__, /*tp_clear*/
+  __pyx_tp_traverse_5_cdec___pyx_scope_struct_8___iter__, /*tp_traverse*/
+  __pyx_tp_clear_5_cdec___pyx_scope_struct_8___iter__, /*tp_clear*/
   0, /*tp_richcompare*/
   0, /*tp_weaklistoffset*/
   0, /*tp_iter*/
   0, /*tp_iternext*/
-  __pyx_methods_5_cdec___pyx_scope_struct_5___iter__, /*tp_methods*/
+  __pyx_methods_5_cdec___pyx_scope_struct_8___iter__, /*tp_methods*/
   0, /*tp_members*/
   0, /*tp_getset*/
   0, /*tp_base*/
@@ -8001,7 +12533,7 @@ static PyTypeObject __pyx_type_5_cdec___pyx_scope_struct_5___iter__ = {
   0, /*tp_dictoffset*/
   0, /*tp_init*/
   0, /*tp_alloc*/
-  __pyx_tp_new_5_cdec___pyx_scope_struct_5___iter__, /*tp_new*/
+  __pyx_tp_new_5_cdec___pyx_scope_struct_8___iter__, /*tp_new*/
   0, /*tp_free*/
   0, /*tp_is_gc*/
   0, /*tp_bases*/
@@ -8039,15 +12571,18 @@ static __Pyx_StringTabEntry __pyx_string_tab[] = {
   {&__pyx_kp_s_11, __pyx_k_11, sizeof(__pyx_k_11), 0, 0, 1, 0},
   {&__pyx_kp_s_13, __pyx_k_13, sizeof(__pyx_k_13), 0, 0, 1, 0},
   {&__pyx_kp_s_14, __pyx_k_14, sizeof(__pyx_k_14), 0, 0, 1, 0},
+  {&__pyx_kp_s_19, __pyx_k_19, sizeof(__pyx_k_19), 0, 0, 1, 0},
   {&__pyx_kp_s_2, __pyx_k_2, sizeof(__pyx_k_2), 0, 0, 1, 0},
-  {&__pyx_kp_s_21, __pyx_k_21, sizeof(__pyx_k_21), 0, 0, 1, 0},
+  {&__pyx_kp_s_23, __pyx_k_23, sizeof(__pyx_k_23), 0, 0, 1, 0},
+  {&__pyx_n_s__BLEU, __pyx_k__BLEU, sizeof(__pyx_k__BLEU), 0, 0, 1, 1},
   {&__pyx_n_s__Exception, __pyx_k__Exception, sizeof(__pyx_k__Exception), 0, 0, 1, 1},
+  {&__pyx_n_s__IBM_BLEU, __pyx_k__IBM_BLEU, sizeof(__pyx_k__IBM_BLEU), 0, 0, 1, 1},
   {&__pyx_n_s__IndexError, __pyx_k__IndexError, sizeof(__pyx_k__IndexError), 0, 0, 1, 1},
   {&__pyx_n_s__KeyError, __pyx_k__KeyError, sizeof(__pyx_k__KeyError), 0, 0, 1, 1},
   {&__pyx_n_s__NotImplemented, __pyx_k__NotImplemented, sizeof(__pyx_k__NotImplemented), 0, 0, 1, 1},
   {&__pyx_n_s__ParseFailed, __pyx_k__ParseFailed, sizeof(__pyx_k__ParseFailed), 0, 0, 1, 1},
+  {&__pyx_n_s__TER, __pyx_k__TER, sizeof(__pyx_k__TER), 0, 0, 1, 1},
   {&__pyx_n_s__TypeError, __pyx_k__TypeError, sizeof(__pyx_k__TypeError), 0, 0, 1, 1},
-  {&__pyx_n_s__ValueError, __pyx_k__ValueError, sizeof(__pyx_k__ValueError), 0, 0, 1, 1},
   {&__pyx_n_s____enter__, __pyx_k____enter__, sizeof(__pyx_k____enter__), 0, 0, 1, 1},
   {&__pyx_n_s____exit__, __pyx_k____exit__, sizeof(__pyx_k____exit__), 0, 0, 1, 1},
   {&__pyx_n_s____main__, __pyx_k____main__, sizeof(__pyx_k____main__), 0, 0, 1, 1},
@@ -8059,13 +12594,19 @@ static __Pyx_StringTabEntry __pyx_string_tab[] = {
   {&__pyx_n_s__density, __pyx_k__density, sizeof(__pyx_k__density), 0, 0, 1, 1},
   {&__pyx_n_s__dot, __pyx_k__dot, sizeof(__pyx_k__dot), 0, 0, 1, 1},
   {&__pyx_n_s__encode, __pyx_k__encode, sizeof(__pyx_k__encode), 0, 0, 1, 1},
+  {&__pyx_n_s__encoding, __pyx_k__encoding, sizeof(__pyx_k__encoding), 0, 0, 1, 1},
   {&__pyx_n_s__enumerate, __pyx_k__enumerate, sizeof(__pyx_k__enumerate), 0, 0, 1, 1},
   {&__pyx_n_s__eval, __pyx_k__eval, sizeof(__pyx_k__eval), 0, 0, 1, 1},
+  {&__pyx_n_s__evaluator, __pyx_k__evaluator, sizeof(__pyx_k__evaluator), 0, 0, 1, 1},
   {&__pyx_n_s__grammar, __pyx_k__grammar, sizeof(__pyx_k__grammar), 0, 0, 1, 1},
+  {&__pyx_n_s__hypergraph, __pyx_k__hypergraph, sizeof(__pyx_k__hypergraph), 0, 0, 1, 1},
   {&__pyx_n_s__inp, __pyx_k__inp, sizeof(__pyx_k__inp), 0, 0, 1, 1},
+  {&__pyx_n_s__k, __pyx_k__k, sizeof(__pyx_k__k), 0, 0, 1, 1},
+  {&__pyx_n_s__name, __pyx_k__name, sizeof(__pyx_k__name), 0, 0, 1, 1},
   {&__pyx_n_s__open, __pyx_k__open, sizeof(__pyx_k__open), 0, 0, 1, 1},
   {&__pyx_n_s__plf, __pyx_k__plf, sizeof(__pyx_k__plf), 0, 0, 1, 1},
   {&__pyx_n_s__range, __pyx_k__range, sizeof(__pyx_k__range), 0, 0, 1, 1},
+  {&__pyx_n_s__refs, __pyx_k__refs, sizeof(__pyx_k__refs), 0, 0, 1, 1},
   {&__pyx_n_s__self, __pyx_k__self, sizeof(__pyx_k__self), 0, 0, 1, 1},
   {&__pyx_n_s__sentence, __pyx_k__sentence, sizeof(__pyx_k__sentence), 0, 0, 1, 1},
   {&__pyx_n_s__split, __pyx_k__split, sizeof(__pyx_k__split), 0, 0, 1, 1},
@@ -8074,14 +12615,13 @@ static __Pyx_StringTabEntry __pyx_string_tab[] = {
   {0, 0, 0, 0, 0, 0, 0}
 };
 static int __Pyx_InitCachedBuiltins(void) {
-  __pyx_builtin_Exception = __Pyx_GetName(__pyx_b, __pyx_n_s__Exception); if (!__pyx_builtin_Exception) {__pyx_filename = __pyx_f[0]; __pyx_lineno = 12; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
-  __pyx_builtin_KeyError = __Pyx_GetName(__pyx_b, __pyx_n_s__KeyError); if (!__pyx_builtin_KeyError) {__pyx_filename = __pyx_f[1]; __pyx_lineno = 10; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
-  __pyx_builtin_range = __Pyx_GetName(__pyx_b, __pyx_n_s__range); if (!__pyx_builtin_range) {__pyx_filename = __pyx_f[1]; __pyx_lineno = 20; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
-  __pyx_builtin_ValueError = __Pyx_GetName(__pyx_b, __pyx_n_s__ValueError); if (!__pyx_builtin_ValueError) {__pyx_filename = __pyx_f[1]; __pyx_lineno = 56; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
-  __pyx_builtin_NotImplemented = __Pyx_GetName(__pyx_b, __pyx_n_s__NotImplemented); if (!__pyx_builtin_NotImplemented) {__pyx_filename = __pyx_f[1]; __pyx_lineno = 69; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
-  __pyx_builtin_eval = __Pyx_GetName(__pyx_b, __pyx_n_s__eval); if (!__pyx_builtin_eval) {__pyx_filename = __pyx_f[2]; __pyx_lineno = 82; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
+  __pyx_builtin_Exception = __Pyx_GetName(__pyx_b, __pyx_n_s__Exception); if (!__pyx_builtin_Exception) {__pyx_filename = __pyx_f[0]; __pyx_lineno = 13; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
+  __pyx_builtin_KeyError = __Pyx_GetName(__pyx_b, __pyx_n_s__KeyError); if (!__pyx_builtin_KeyError) {__pyx_filename = __pyx_f[1]; __pyx_lineno = 13; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
+  __pyx_builtin_range = __Pyx_GetName(__pyx_b, __pyx_n_s__range); if (!__pyx_builtin_range) {__pyx_filename = __pyx_f[1]; __pyx_lineno = 24; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
+  __pyx_builtin_TypeError = __Pyx_GetName(__pyx_b, __pyx_n_s__TypeError); if (!__pyx_builtin_TypeError) {__pyx_filename = __pyx_f[1]; __pyx_lineno = 69; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
+  __pyx_builtin_NotImplemented = __Pyx_GetName(__pyx_b, __pyx_n_s__NotImplemented); if (!__pyx_builtin_NotImplemented) {__pyx_filename = __pyx_f[1]; __pyx_lineno = 76; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
+  __pyx_builtin_eval = __Pyx_GetName(__pyx_b, __pyx_n_s__eval); if (!__pyx_builtin_eval) {__pyx_filename = __pyx_f[2]; __pyx_lineno = 105; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
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-  /* "/Users/vchahun/Sandbox/cdec/python/src/vectors.pxi":69
+  /* "/Users/vchahun/Sandbox/cdec/python/src/vectors.pxi":76
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+  __pyx_k_tuple_3 = PyTuple_New(1); if (unlikely(!__pyx_k_tuple_3)) {__pyx_filename = __pyx_f[1]; __pyx_lineno = 76; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
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- *             yield sentence.decode('utf8')             # <<<<<<<<<<<<<<
- *         del derivations
- * 
+  /* "/Users/vchahun/Sandbox/cdec/python/src/hypergraph.pxi":42
+ *                 if not derivation: break
+ *                 sentence = GetString(derivation._yield).c_str()
+ *                 yield sentence.decode('utf8')             # <<<<<<<<<<<<<<
+ *         finally:
+ *             del derivations
  */
-  __pyx_k_tuple_7 = PyTuple_New(1); if (unlikely(!__pyx_k_tuple_7)) {__pyx_filename = __pyx_f[2]; __pyx_lineno = 41; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
+  __pyx_k_tuple_7 = PyTuple_New(1); if (unlikely(!__pyx_k_tuple_7)) {__pyx_filename = __pyx_f[2]; __pyx_lineno = 42; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
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- *             yield tree.decode('utf8')             # <<<<<<<<<<<<<<
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+ *                 if not derivation: break
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- *             yield sentence.decode('utf8')             # <<<<<<<<<<<<<<
- *         del hypos
- * 
+  /* "/Users/vchahun/Sandbox/cdec/python/src/hypergraph.pxi":85
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   __Pyx_GIVEREF(((PyObject *)__pyx_k_tuple_18));
 
+  /* "/Users/vchahun/Sandbox/cdec/python/src/mteval.pxi":6
+ *     cdef bytes ret
+ *     if isinstance(sentence, unicode):
+ *         ret = sentence.encode('utf8')             # <<<<<<<<<<<<<<
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+  __Pyx_INCREF(((PyObject *)__pyx_n_s__utf8));
+  PyTuple_SET_ITEM(__pyx_k_tuple_20, 0, ((PyObject *)__pyx_n_s__utf8));
+  __Pyx_GIVEREF(((PyObject *)__pyx_n_s__utf8));
+  __Pyx_GIVEREF(((PyObject *)__pyx_k_tuple_20));
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-  PyTuple_SET_ITEM(__pyx_k_tuple_19, 0, Py_None);
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   __Pyx_GIVEREF(Py_None);
   __Pyx_INCREF(Py_None);
-  PyTuple_SET_ITEM(__pyx_k_tuple_19, 1, Py_None);
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-  __Pyx_GOTREF(__pyx_k_tuple_20);
+  __pyx_k_tuple_22 = PyTuple_New(1); if (unlikely(!__pyx_k_tuple_22)) {__pyx_filename = __pyx_f[0]; __pyx_lineno = 38; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
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   __Pyx_INCREF(((PyObject *)__pyx_n_s__utf8));
-  PyTuple_SET_ITEM(__pyx_k_tuple_20, 0, ((PyObject *)__pyx_n_s__utf8));
+  PyTuple_SET_ITEM(__pyx_k_tuple_22, 0, ((PyObject *)__pyx_n_s__utf8));
   __Pyx_GIVEREF(((PyObject *)__pyx_n_s__utf8));
-  __Pyx_GIVEREF(((PyObject *)__pyx_k_tuple_20));
+  __Pyx_GIVEREF(((PyObject *)__pyx_k_tuple_22));
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+ * BLEU = Scorer('IBM_BLEU')             # <<<<<<<<<<<<<<
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+  /* "/Users/vchahun/Sandbox/cdec/python/src/mteval.pxi":141
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+  PyTuple_SET_ITEM(__pyx_k_tuple_25, 0, ((PyObject *)__pyx_n_s__TER));
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+  if (__Pyx_SetAttrString(__pyx_m, "CandidateSet", (PyObject *)&__pyx_type_5_cdec_CandidateSet) < 0) {__pyx_filename = __pyx_f[4]; __pyx_lineno = 59; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
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+  if (__Pyx_SetAttrString(__pyx_m, "SegmentEvaluator", (PyObject *)&__pyx_type_5_cdec_SegmentEvaluator) < 0) {__pyx_filename = __pyx_f[4]; __pyx_lineno = 90; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
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+  if (PyType_Ready(&__pyx_type_5_cdec___pyx_scope_struct_5_sample) < 0) {__pyx_filename = __pyx_f[2]; __pyx_lineno = 75; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
+  __pyx_ptype_5_cdec___pyx_scope_struct_5_sample = &__pyx_type_5_cdec___pyx_scope_struct_5_sample;
+  if (PyType_Ready(&__pyx_type_5_cdec___pyx_scope_struct_6___iter__) < 0) {__pyx_filename = __pyx_f[3]; __pyx_lineno = 50; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
+  __pyx_ptype_5_cdec___pyx_scope_struct_6___iter__ = &__pyx_type_5_cdec___pyx_scope_struct_6___iter__;
+  if (PyType_Ready(&__pyx_type_5_cdec___pyx_scope_struct_7___iter__) < 0) {__pyx_filename = __pyx_f[4]; __pyx_lineno = 45; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
+  __pyx_ptype_5_cdec___pyx_scope_struct_7___iter__ = &__pyx_type_5_cdec___pyx_scope_struct_7___iter__;
+  if (PyType_Ready(&__pyx_type_5_cdec___pyx_scope_struct_8___iter__) < 0) {__pyx_filename = __pyx_f[4]; __pyx_lineno = 82; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
+  __pyx_ptype_5_cdec___pyx_scope_struct_8___iter__ = &__pyx_type_5_cdec___pyx_scope_struct_8___iter__;
   /*--- Type import code ---*/
   /*--- Variable import code ---*/
   /*--- Function import code ---*/
   /*--- Execution code ---*/
 
-  /* "_cdec.pyx":10
- * include "lattice.pxi"
+  /* "/Users/vchahun/Sandbox/cdec/python/src/mteval.pxi":140
+ *         return self.name.c_str()
+ * 
+ * BLEU = Scorer('IBM_BLEU')             # <<<<<<<<<<<<<<
+ * TER = Scorer('TER')
+ */
+  __pyx_t_1 = PyObject_Call(((PyObject *)((PyObject*)__pyx_ptype_5_cdec_Scorer)), ((PyObject *)__pyx_k_tuple_24), NULL); if (unlikely(!__pyx_t_1)) {__pyx_filename = __pyx_f[4]; __pyx_lineno = 140; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
+  __Pyx_GOTREF(__pyx_t_1);
+  if (PyObject_SetAttr(__pyx_m, __pyx_n_s__BLEU, __pyx_t_1) < 0) {__pyx_filename = __pyx_f[4]; __pyx_lineno = 140; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
+  __Pyx_DECREF(__pyx_t_1); __pyx_t_1 = 0;
+
+  /* "/Users/vchahun/Sandbox/cdec/python/src/mteval.pxi":141
+ * 
+ * BLEU = Scorer('IBM_BLEU')
+ * TER = Scorer('TER')             # <<<<<<<<<<<<<<
+ */
+  __pyx_t_1 = PyObject_Call(((PyObject *)((PyObject*)__pyx_ptype_5_cdec_Scorer)), ((PyObject *)__pyx_k_tuple_25), NULL); if (unlikely(!__pyx_t_1)) {__pyx_filename = __pyx_f[4]; __pyx_lineno = 141; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
+  __Pyx_GOTREF(__pyx_t_1);
+  if (PyObject_SetAttr(__pyx_m, __pyx_n_s__TER, __pyx_t_1) < 0) {__pyx_filename = __pyx_f[4]; __pyx_lineno = 141; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
+  __Pyx_DECREF(__pyx_t_1); __pyx_t_1 = 0;
+
+  /* "_cdec.pyx":11
+ * include "mteval.pxi"
  * 
  * SetSilent(True)             # <<<<<<<<<<<<<<
  * 
- * class ParseFailed(Exception):
+ * class ParseFailed(Exception): pass
  */
   SetSilent(1);
 
-  /* "_cdec.pyx":12
+  /* "_cdec.pyx":13
  * SetSilent(True)
  * 
- * class ParseFailed(Exception):             # <<<<<<<<<<<<<<
- *     pass
+ * class ParseFailed(Exception): pass             # <<<<<<<<<<<<<<
  * 
+ * cdef class Decoder:
  */
-  __pyx_t_1 = PyDict_New(); if (unlikely(!__pyx_t_1)) {__pyx_filename = __pyx_f[0]; __pyx_lineno = 12; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
+  __pyx_t_1 = PyDict_New(); if (unlikely(!__pyx_t_1)) {__pyx_filename = __pyx_f[0]; __pyx_lineno = 13; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
   __Pyx_GOTREF(((PyObject *)__pyx_t_1));
-  __pyx_t_2 = PyTuple_New(1); if (unlikely(!__pyx_t_2)) {__pyx_filename = __pyx_f[0]; __pyx_lineno = 12; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
+  __pyx_t_2 = PyTuple_New(1); if (unlikely(!__pyx_t_2)) {__pyx_filename = __pyx_f[0]; __pyx_lineno = 13; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
   __Pyx_GOTREF(__pyx_t_2);
   __Pyx_INCREF(__pyx_builtin_Exception);
   PyTuple_SET_ITEM(__pyx_t_2, 0, __pyx_builtin_Exception);
   __Pyx_GIVEREF(__pyx_builtin_Exception);
-  __pyx_t_3 = __Pyx_CreateClass(((PyObject *)__pyx_t_2), ((PyObject *)__pyx_t_1), __pyx_n_s__ParseFailed, __pyx_n_s___cdec); if (unlikely(!__pyx_t_3)) {__pyx_filename = __pyx_f[0]; __pyx_lineno = 12; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
+  __pyx_t_3 = __Pyx_CreateClass(((PyObject *)__pyx_t_2), ((PyObject *)__pyx_t_1), __pyx_n_s__ParseFailed, __pyx_n_s___cdec); if (unlikely(!__pyx_t_3)) {__pyx_filename = __pyx_f[0]; __pyx_lineno = 13; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
   __Pyx_GOTREF(__pyx_t_3);
   __Pyx_DECREF(((PyObject *)__pyx_t_2)); __pyx_t_2 = 0;
-  if (PyObject_SetAttr(__pyx_m, __pyx_n_s__ParseFailed, __pyx_t_3) < 0) {__pyx_filename = __pyx_f[0]; __pyx_lineno = 12; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
+  if (PyObject_SetAttr(__pyx_m, __pyx_n_s__ParseFailed, __pyx_t_3) < 0) {__pyx_filename = __pyx_f[0]; __pyx_lineno = 13; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
   __Pyx_DECREF(__pyx_t_3); __pyx_t_3 = 0;
   __Pyx_DECREF(((PyObject *)__pyx_t_1)); __pyx_t_1 = 0;
 
@@ -8673,6 +13294,18 @@ static int __Pyx_ArgTypeTest(PyObject *obj, PyTypeObject *type, int none_allowed
     return 0;
 }
 
+static CYTHON_INLINE int __Pyx_TypeTest(PyObject *obj, PyTypeObject *type) {
+    if (unlikely(!type)) {
+        PyErr_Format(PyExc_SystemError, "Missing type object");
+        return 0;
+    }
+    if (likely(PyObject_TypeCheck(obj, type)))
+        return 1;
+    PyErr_Format(PyExc_TypeError, "Cannot convert %.200s to %.200s",
+                 Py_TYPE(obj)->tp_name, type->tp_name);
+    return 0;
+}
+
 static void __Pyx_RaiseDoubleKeywordsError(
     const char* func_name,
     PyObject* kw_name)
@@ -8889,18 +13522,6 @@ bad:
     return -1;
 }
 
-static CYTHON_INLINE int __Pyx_TypeTest(PyObject *obj, PyTypeObject *type) {
-    if (unlikely(!type)) {
-        PyErr_Format(PyExc_SystemError, "Missing type object");
-        return 0;
-    }
-    if (likely(PyObject_TypeCheck(obj, type)))
-        return 1;
-    PyErr_Format(PyExc_TypeError, "Cannot convert %.200s to %.200s",
-                 Py_TYPE(obj)->tp_name, type->tp_name);
-    return 0;
-}
-
 static CYTHON_INLINE void __Pyx_ExceptionSave(PyObject **type, PyObject **value, PyObject **tb) {
     PyThreadState *tstate = PyThreadState_GET();
     *type = tstate->exc_type;
@@ -9693,6 +14314,25 @@ static int __pyx_Generator_init(void)
     return PyType_Ready(&__pyx_GeneratorType);
 }
 
+static void __Pyx_WriteUnraisable(const char *name, int clineno,
+                                  int lineno, const char *filename) {
+    PyObject *old_exc, *old_val, *old_tb;
+    PyObject *ctx;
+    __Pyx_ErrFetch(&old_exc, &old_val, &old_tb);
+    #if PY_MAJOR_VERSION < 3
+    ctx = PyString_FromString(name);
+    #else
+    ctx = PyUnicode_FromString(name);
+    #endif
+    __Pyx_ErrRestore(old_exc, old_val, old_tb);
+    if (!ctx) {
+        PyErr_WriteUnraisable(Py_None);
+    } else {
+        PyErr_WriteUnraisable(ctx);
+        Py_DECREF(ctx);
+    }
+}
+
 static int __Pyx_check_binary_version(void) {
     char ctversion[4], rtversion[4];
     PyOS_snprintf(ctversion, 4, "%d.%d", PY_MAJOR_VERSION, PY_MINOR_VERSION);
diff --git a/python/src/_cdec.pyx b/python/src/_cdec.pyx
index 698a66f6..6fafbbc0 100644
--- a/python/src/_cdec.pyx
+++ b/python/src/_cdec.pyx
@@ -6,11 +6,11 @@ cimport decoder
 include "vectors.pxi"
 include "hypergraph.pxi"
 include "lattice.pxi"
+include "mteval.pxi"
 
 SetSilent(True)
 
-class ParseFailed(Exception):
-    pass
+class ParseFailed(Exception): pass
 
 cdef class Decoder:
     cdef decoder.Decoder* dec
diff --git a/python/src/hypergraph.pxi b/python/src/hypergraph.pxi
index c226d105..9d09722e 100644
--- a/python/src/hypergraph.pxi
+++ b/python/src/hypergraph.pxi
@@ -32,26 +32,45 @@ cdef class Hypergraph:
     def kbest(self, size):
         cdef kb.KBestDerivations[vector[WordID], kb.ESentenceTraversal]* derivations = new kb.KBestDerivations[vector[WordID], kb.ESentenceTraversal](self.hg[0], size)
         cdef kb.KBestDerivations[vector[WordID], kb.ESentenceTraversal].Derivation* derivation
-        cdef str sentence
+        cdef bytes sentence
         cdef unsigned k
-        for k in range(size):
-            derivation = derivations.LazyKthBest(self.hg.nodes_.size() - 1, k)
-            if not derivation: break
-            sentence = GetString(derivation._yield).c_str()
-            yield sentence.decode('utf8')
-        del derivations
+        try:
+            for k in range(size):
+                derivation = derivations.LazyKthBest(self.hg.nodes_.size() - 1, k)
+                if not derivation: break
+                sentence = GetString(derivation._yield).c_str()
+                yield sentence.decode('utf8')
+        finally:
+            del derivations
 
     def kbest_tree(self, size):
         cdef kb.KBestDerivations[vector[WordID], kb.ETreeTraversal]* derivations = new kb.KBestDerivations[vector[WordID], kb.ETreeTraversal](self.hg[0], size)
         cdef kb.KBestDerivations[vector[WordID], kb.ETreeTraversal].Derivation* derivation
         cdef str tree
         cdef unsigned k
-        for k in range(size):
-            derivation = derivations.LazyKthBest(self.hg.nodes_.size() - 1, k)
-            if not derivation: break
-            tree = GetString(derivation._yield).c_str()
-            yield tree.decode('utf8')
-        del derivations
+        try:
+            for k in range(size):
+                derivation = derivations.LazyKthBest(self.hg.nodes_.size() - 1, k)
+                if not derivation: break
+                tree = GetString(derivation._yield).c_str()
+                yield tree.decode('utf8')
+        finally:
+            del derivations
+
+    def kbest_features(self, size):
+        cdef kb.KBestDerivations[FastSparseVector[weight_t], kb.FeatureVectorTraversal]* derivations = new kb.KBestDerivations[FastSparseVector[weight_t], kb.FeatureVectorTraversal](self.hg[0], size)
+        cdef kb.KBestDerivations[FastSparseVector[weight_t], kb.FeatureVectorTraversal].Derivation* derivation
+        cdef SparseVector fmap
+        cdef unsigned k
+        try:
+            for k in range(size):
+                derivation = derivations.LazyKthBest(self.hg.nodes_.size() - 1, k)
+                if not derivation: break
+                fmap = SparseVector()
+                fmap.vector = new FastSparseVector[weight_t](derivation._yield)
+                yield fmap
+        finally:
+            del derivations
 
     def sample(self, unsigned n):
         cdef vector[hypergraph.Hypothesis]* hypos = new vector[hypergraph.Hypothesis]()
@@ -60,10 +79,12 @@ cdef class Hypergraph:
         hypergraph.sample_hypotheses(self.hg[0], n, self.rng, hypos)
         cdef str sentence
         cdef unsigned k
-        for k in range(hypos.size()):
-            sentence = GetString(hypos[0][k].words).c_str()
-            yield sentence.decode('utf8')
-        del hypos
+        try:
+            for k in range(hypos.size()):
+                sentence = GetString(hypos[0][k].words).c_str()
+                yield sentence.decode('utf8')
+        finally:
+            del hypos
 
     # TODO richer k-best/sample output (feature vectors, trees?)
 
@@ -76,6 +97,8 @@ cdef class Hypergraph:
              preserve_mask = new hypergraph.EdgeMask(self.hg.edges_.size())
              preserve_mask[0][hypergraph.GetFullWordEdgeIndex(self.hg[0])] = True
         self.hg.PruneInsideOutside(beam_alpha, density, preserve_mask, False, 1, False)
+        if preserve_mask:
+            del preserve_mask
 
     def lattice(self): # TODO direct hg -> lattice conversion in cdec
         cdef str plf = hypergraph.AsPLF(self.hg[0], True).c_str()
@@ -87,6 +110,6 @@ cdef class Hypergraph:
         elif isinstance(weights, DenseVector):
             self.hg.Reweight((<DenseVector> weights).vector[0])
         else:
-            raise ValueError('cannot reweight hypergraph with %s' % type(weights))
+            raise TypeError('cannot reweight hypergraph with %s' % type(weights))
 
     # TODO get feature expectations, get partition function ("inside" score)
diff --git a/python/src/kbest.pxd b/python/src/kbest.pxd
index f34ac5ed..cef42bd3 100644
--- a/python/src/kbest.pxd
+++ b/python/src/kbest.pxd
@@ -9,6 +9,8 @@ cdef extern from "decoder/viterbi.h":
         pass
     cdef cppclass FTreeTraversal:
         pass
+    cdef cppclass FeatureVectorTraversal:
+        pass
 
 cdef extern from "decoder/kbest.h" namespace "KBest":
     cdef cppclass KBestDerivations[T, Traversal]:
diff --git a/python/src/mteval.pxd b/python/src/mteval.pxd
new file mode 100644
index 00000000..52af6297
--- /dev/null
+++ b/python/src/mteval.pxd
@@ -0,0 +1,47 @@
+from libcpp.vector cimport vector
+from libcpp.string cimport string
+from utils cimport *
+from hypergraph cimport Hypergraph
+
+cdef extern from "mteval/ns.h":
+    cdef cppclass SufficientStats:
+        SufficientStats()
+        SufficientStats(SufficientStats&)
+        unsigned size()
+        float operator[](unsigned i)
+        void swap(SufficientStats& other)
+
+    SufficientStats add "operator+" (SufficientStats&, SufficientStats&)
+
+    cdef cppclass SegmentEvaluator:
+        void Evaluate(vector[WordID]& hyp, SufficientStats* out)
+
+    cdef cppclass EvaluationMetric:
+        string& MetricId()
+        bint IsErrorMetric()
+        float ComputeScore(SufficientStats& stats)
+        string DetailedScore(SufficientStats& stats)
+        shared_ptr[SegmentEvaluator] CreateSegmentEvaluator(vector[vector[WordID]]& refs)
+        ComputeSufficientStatistics(vector[WordID]& hyp,
+                                    vector[WordID]& refs,
+                                    SufficientStats* out)
+
+cdef extern from "mteval/ns.h" namespace "EvaluationMetric":
+    EvaluationMetric* Instance(string& metric_id)
+    EvaluationMetric* Instance() # IBM_BLEU
+
+cdef extern from "training/candidate_set.h" namespace "training":
+    cdef cppclass Candidate "const training::Candidate":
+        vector[WordID] ewords
+        FastSparseVector[weight_t] fmap
+        SufficientStats eval_feats
+
+    cdef cppclass CandidateSet:
+        CandidateSet()
+        unsigned size()
+        Candidate& operator[](unsigned i)
+        void ReadFromFile(string& file)
+        void WriteToFile(string& file)
+        void AddKBestCandidates(Hypergraph& hg,
+                unsigned kbest_size,
+                SegmentEvaluator* scorer)
diff --git a/python/src/mteval.pxi b/python/src/mteval.pxi
new file mode 100644
index 00000000..9afb6fe1
--- /dev/null
+++ b/python/src/mteval.pxi
@@ -0,0 +1,141 @@
+cimport mteval
+
+cdef char* as_str(sentence, error_msg='Cannot convert type %s to str'):
+    cdef bytes ret
+    if isinstance(sentence, unicode):
+        ret = sentence.encode('utf8')
+    elif isinstance(sentence, str):
+        ret = sentence
+    else:
+        raise TypeError(error_msg % type(sentence))
+    return ret
+
+cdef class Candidate:
+    cdef mteval.Candidate* candidate
+    cdef public float score
+
+    property words:
+        def __get__(self):
+            return unicode(GetString(self.candidate.ewords).c_str(), encoding='utf8')
+
+    property fmap:
+        def __get__(self):
+            cdef SparseVector fmap = SparseVector()
+            fmap.vector = new FastSparseVector[weight_t](self.candidate.fmap)
+            return fmap
+
+cdef class SufficientStats:
+    cdef mteval.SufficientStats* stats
+    cdef mteval.EvaluationMetric* metric
+
+    def __dealloc__(self):
+        del self.stats
+
+    property score:
+        def __get__(self):
+            return self.metric.ComputeScore(self.stats[0])
+
+    property detail:
+        def __get__(self):
+            return self.metric.DetailedScore(self.stats[0]).c_str()
+
+    def __len__(self):
+        return self.stats.size()
+
+    def __iter__(self):
+        for i in range(len(self)):
+            yield self.stats[0][i]
+
+    def __iadd__(SufficientStats self, SufficientStats other):
+        self.stats[0] += other.stats[0]
+        return self
+
+    def __add__(SufficientStats x, SufficientStats y):
+        cdef SufficientStats result = SufficientStats()
+        result.stats = new mteval.SufficientStats(mteval.add(x.stats[0], y.stats[0]))
+        result.metric = x.metric
+        return result
+
+cdef class CandidateSet:
+    cdef shared_ptr[mteval.SegmentEvaluator]* scorer
+    cdef mteval.EvaluationMetric* metric
+    cdef mteval.CandidateSet* cs
+
+    def __cinit__(self, SegmentEvaluator evaluator):
+        self.scorer = new shared_ptr[mteval.SegmentEvaluator](evaluator.scorer[0])
+        self.metric = evaluator.metric
+        self.cs = new mteval.CandidateSet()
+
+    def __dealloc__(self):
+        del self.scorer
+        del self.cs
+
+    def __len__(self):
+        return self.cs.size()
+
+    def __getitem__(self, unsigned k):
+        cdef Candidate candidate = Candidate()
+        candidate.candidate = &self.cs[0][k]
+        candidate.score = self.metric.ComputeScore(self.cs[0][k].eval_feats)
+        return candidate
+
+    def __iter__(self):
+        cdef unsigned i
+        for i in range(len(self)):
+            yield self[i]
+
+    def add_kbest(self, Hypergraph hypergraph, unsigned k):
+        self.cs.AddKBestCandidates(hypergraph.hg[0], k, self.scorer.get())
+
+cdef class SegmentEvaluator:
+    cdef shared_ptr[mteval.SegmentEvaluator]* scorer
+    cdef mteval.EvaluationMetric* metric
+    
+    def __dealloc__(self):
+        del self.scorer
+
+    def evaluate(self, sentence):
+        cdef vector[WordID] hyp
+        cdef SufficientStats sf = SufficientStats()
+        sf.metric = self.metric
+        sf.stats = new mteval.SufficientStats()
+        ConvertSentence(string(as_str(sentence.strip())), &hyp)
+        self.scorer.get().Evaluate(hyp, sf.stats)
+        return sf
+
+    def candidate_set(self):
+        return CandidateSet(self)
+
+cdef class Scorer:
+    cdef string* name
+
+    def __cinit__(self, char* name):
+        self.name = new string(name)
+
+    def __dealloc__(self):
+        del self.name
+    
+    def __call__(self, refs):
+        cdef mteval.EvaluationMetric* metric = mteval.Instance(self.name[0])
+        if isinstance(refs, unicode) or isinstance(refs, str):
+            refs = [refs]
+        cdef vector[vector[WordID]]* refsv = new vector[vector[WordID]]()
+        cdef vector[WordID]* refv
+        cdef bytes ref_str
+        for ref in refs:
+            refv = new vector[WordID]()
+            ConvertSentence(string(as_str(ref.strip())), refv)
+            refsv.push_back(refv[0])
+            del refv
+        cdef unsigned i
+        cdef SegmentEvaluator evaluator = SegmentEvaluator()
+        evaluator.metric = metric
+        evaluator.scorer = new shared_ptr[mteval.SegmentEvaluator](metric.CreateSegmentEvaluator(refsv[0]))
+        del refsv # in theory should not delete but store in SegmentEvaluator
+        return evaluator
+
+    def __str__(self):
+        return self.name.c_str()
+
+BLEU = Scorer('IBM_BLEU')
+TER = Scorer('TER')
diff --git a/python/src/utils.pxd b/python/src/utils.pxd
index 3d518524..94fab5ef 100644
--- a/python/src/utils.pxd
+++ b/python/src/utils.pxd
@@ -50,16 +50,19 @@ cdef extern from "utils/sparse_vector.h":
 
     FastSparseVector[weight_t] operator+(FastSparseVector[weight_t]&, FastSparseVector[weight_t]&)
     FastSparseVector[weight_t] operator-(FastSparseVector[weight_t]&, FastSparseVector[weight_t]&)
+    FastSparseVector[weight_t] operator*(FastSparseVector[weight_t]&, double&)
+    FastSparseVector[weight_t] operator/(FastSparseVector[weight_t]&, double&)
     ostream operator<<(ostream& out, FastSparseVector[weight_t]& v)
 
 cdef extern from "utils/weights.h" namespace "Weights":
     void InitSparseVector(vector[weight_t]& dv, FastSparseVector[weight_t]* sv)
 
-cdef extern from "utils/tdict.cc" namespace "TD":
+cdef extern from "utils/tdict.h" namespace "TD":
     string GetString(vector[WordID]& st)
     unsigned NumWords()
     WordID TDConvert "TD::Convert" (char*)
     char* TDConvert "TD::Convert" (WordID)
+    void ConvertSentence(string& sent, vector[WordID]* ids)
 
 cdef extern from "utils/verbose.h":
     void SetSilent(bint)
@@ -76,3 +79,8 @@ cdef extern from "utils/filelib.h":
 cdef extern from "utils/sampler.h":
     cdef cppclass MT19937:
         pass
+
+cdef extern from "<boost/shared_ptr.hpp>" namespace "boost":
+    cdef cppclass shared_ptr[T]:
+        shared_ptr(shared_ptr& r)
+        T* get()
diff --git a/python/src/vectors.pxi b/python/src/vectors.pxi
index 74d3a0bd..fc0c365f 100644
--- a/python/src/vectors.pxi
+++ b/python/src/vectors.pxi
@@ -1,16 +1,20 @@
 from cython.operator cimport preincrement as pinc
 
 cdef class DenseVector:
-    cdef vector[weight_t]* vector
+    cdef vector[weight_t]* vector # Not owned by DenseVector
+
+    def __len__(self):
+        return self.vector.size()
 
     def __getitem__(self, char* fname):
-        cdef unsigned fid = FDConvert(fname)
-        if fid <= self.vector.size():
+        cdef int fid = FDConvert(fname)
+        if 0 <= fid < self.vector.size():
             return self.vector[0][fid]
         raise KeyError(fname)
     
     def __setitem__(self, char* fname, float value):
-        cdef unsigned fid = FDConvert(<char *>fname)
+        cdef int fid = FDConvert(<char *>fname)
+        if fid < 0: raise KeyError(fname)
         if self.vector.size() <= fid:
             self.vector.resize(fid + 1)
         self.vector[0][fid] = value
@@ -32,40 +36,43 @@ cdef class DenseVector:
 cdef class SparseVector:
     cdef FastSparseVector[weight_t]* vector
 
+    def __dealloc__(self):
+        del self.vector
+
+    def copy(self):
+        return self * 1
+
     def __getitem__(self, char* fname):
-        cdef unsigned fid = FDConvert(fname)
+        cdef int fid = FDConvert(fname)
+        if fid < 0: raise KeyError(fname)
         return self.vector.value(fid)
     
     def __setitem__(self, char* fname, float value):
-        cdef unsigned fid = FDConvert(<char *>fname)
+        cdef int fid = FDConvert(<char *>fname)
+        if fid < 0: raise KeyError(fname)
         self.vector.set_value(fid, value)
 
     def __iter__(self):
         cdef FastSparseVector[weight_t].const_iterator* it = new FastSparseVector[weight_t].const_iterator(self.vector[0], False)
-        cdef str fname
-        for i in range(self.vector.size()):
-            fname = FDConvert(it[0].ptr().first).c_str()
-            yield (fname, it[0].ptr().second)
-            pinc(it[0])
+        try:
+            for i in range(self.vector.size()):
+                yield (FDConvert(it[0].ptr().first).c_str(), it[0].ptr().second)
+                pinc(it[0]) # ++it
+        finally:
+            del it
 
     def dot(self, other):
         if isinstance(other, DenseVector):
             return self.vector.dot((<DenseVector> other).vector[0])
         elif isinstance(other, SparseVector):
             return self.vector.dot((<SparseVector> other).vector[0])
-        raise ValueError('cannot take the dot product of %s and SparseVector' % type(other))
-
-    def todense(self):
-        cdef DenseVector dense = DenseVector()
-        dense.vector = new vector[weight_t]()
-        self.vector.init_vector(dense.vector)
-        return dense
+        raise TypeError('cannot take the dot product of %s and SparseVector' % type(other))
     
-    def __richcmp__(SparseVector self, SparseVector other, int op):
+    def __richcmp__(SparseVector x, SparseVector y, int op):
         if op == 2: # ==
-            return self.vector[0] == other.vector[0]
+            return x.vector[0] == y.vector[0]
         elif op == 3: # !=
-            return not (self == other)
+            return not (x == y)
         raise NotImplemented('comparison not implemented for SparseVector')
 
     def __len__(self):
@@ -90,12 +97,30 @@ cdef class SparseVector:
         self.vector[0] /= scalar
         return self
 
-    def __add__(SparseVector self, SparseVector other):
+    def __add__(SparseVector x, SparseVector y):
+        cdef SparseVector result = SparseVector()
+        result.vector = new FastSparseVector[weight_t](x.vector[0] + y.vector[0])
+        return result
+
+    def __sub__(SparseVector x, SparseVector y):
+        cdef SparseVector result = SparseVector()
+        result.vector = new FastSparseVector[weight_t](x.vector[0] - y.vector[0])
+        return result
+
+    def __mul__(x, y):
+        cdef SparseVector vector
+        cdef float scalar
+        if isinstance(x, SparseVector): vector, scalar = x, y
+        else: vector, scalar = y, x
         cdef SparseVector result = SparseVector()
-        result.vector = new FastSparseVector[weight_t](self.vector[0] + other.vector[0])
+        result.vector = new FastSparseVector[weight_t](vector.vector[0] * scalar)
         return result
 
-    def __sub__(SparseVector self, SparseVector other):
+    def __div__(x, y):
+        cdef SparseVector vector
+        cdef float scalar
+        if isinstance(x, SparseVector): vector, scalar = x, y
+        else: vector, scalar = y, x
         cdef SparseVector result = SparseVector()
-        result.vector = new FastSparseVector[weight_t](self.vector[0] - other.vector[0])
+        result.vector = new FastSparseVector[weight_t](vector.vector[0] / scalar)
         return result
diff --git a/python/test.py b/python/test.py
index 92403298..8069aa0a 100644
--- a/python/test.py
+++ b/python/test.py
@@ -31,9 +31,11 @@ print ' FTree[0]:', forest.viterbi_source_tree().encode('utf8')
 print 'LgProb[0]:', forest.viterbi_features().dot(decoder.weights)
 
 # Get k-best translations
-for i, (sentence, tree) in enumerate(zip(forest.kbest(5), forest.kbest_tree(5)), 1):
+kbest = zip(forest.kbest(5), forest.kbest_tree(5), forest.kbest_features(5))
+for i, (sentence, tree, features) in enumerate(kbest, 1):
     print 'Output[%d]:' % i, sentence.encode('utf8')
     print '  Tree[%d]:' % i, tree.encode('utf8')
+    print ' FVect[%d]:' % i, dict(features)
 
 # Sample translations from the forest
 for sentence in forest.sample(5):
@@ -58,3 +60,6 @@ print forest.viterbi_source_tree()
 # Compare 1best and reference feature vectors
 fref = forest.viterbi_features()
 print dict(fsrc - fref)
+
+# Prune hypergraph
+forest.prune(density=100)
diff --git a/training/Makefile.am b/training/Makefile.am
index 68ebfab4..4cef0d5b 100644
--- a/training/Makefile.am
+++ b/training/Makefile.am
@@ -26,6 +26,7 @@ TESTS = lbfgs_test optimize_test
 noinst_LIBRARIES = libtraining.a
 libtraining_a_SOURCES = \
   candidate_set.cc \
+  entropy.cc \
   optimize.cc \
   online_optimizer.cc \
   risk.cc
diff --git a/training/candidate_set.cc b/training/candidate_set.cc
index 8c086ece..087efec3 100644
--- a/training/candidate_set.cc
+++ b/training/candidate_set.cc
@@ -4,6 +4,7 @@
 
 #include <boost/functional/hash.hpp>
 
+#include "verbose.h"
 #include "ns.h"
 #include "filelib.h"
 #include "wordid.h"
@@ -118,7 +119,7 @@ void CandidateSet::WriteToFile(const string& file) const {
 }
 
 void CandidateSet::ReadFromFile(const string& file) {
-  cerr << "Reading candidates from " << file << endl;
+  if(!SILENT) cerr << "Reading candidates from " << file << endl;
   ReadFile rf(file);
   istream& in = *rf.stream();
   string cand;
@@ -133,11 +134,11 @@ void CandidateSet::ReadFromFile(const string& file) {
     ParseSparseVector(feats, 0, &cs.back().fmap);
     cs.back().eval_feats = SufficientStats(ss);
   }
-  cerr << "  read " << cs.size() << " candidates\n";
+  if(!SILENT) cerr << "  read " << cs.size() << " candidates\n";
 }
 
 void CandidateSet::Dedup() {
-  cerr << "Dedup in=" << cs.size();
+  if(!SILENT) cerr << "Dedup in=" << cs.size();
   tr1::unordered_set<Candidate, CandidateHasher, CandidateCompare> u;
   while(cs.size() > 0) {
     u.insert(cs.back());
@@ -148,7 +149,7 @@ void CandidateSet::Dedup() {
     cs.push_back(*it);
     it = u.erase(it);
   }
-  cerr << "  out=" << cs.size() << endl;
+  if(!SILENT) cerr << "  out=" << cs.size() << endl;
 }
 
 void CandidateSet::AddKBestCandidates(const Hypergraph& hg, size_t kbest_size, const SegmentEvaluator* scorer) {
diff --git a/training/entropy.cc b/training/entropy.cc
new file mode 100644
index 00000000..4fdbe2be
--- /dev/null
+++ b/training/entropy.cc
@@ -0,0 +1,41 @@
+#include "entropy.h"
+
+#include "prob.h"
+#include "candidate_set.h"
+
+using namespace std;
+
+namespace training {
+
+// see Mann and McCallum "Efficient Computation of Entropy Gradient ..." for
+// a mostly clear derivation of:
+//   g = E[ F(x,y) * log p(y|x) ] + H(y | x) * E[ F(x,y) ]
+double CandidateSetEntropy::operator()(const vector<double>& params,
+                                       SparseVector<double>* g) const {
+  prob_t z;
+  vector<double> dps(cands_.size());
+  for (unsigned i = 0; i < cands_.size(); ++i) {
+    dps[i] = cands_[i].fmap.dot(params);
+    const prob_t u(dps[i], init_lnx());
+    z += u;
+  }
+  const double log_z = log(z);
+
+  SparseVector<double> exp_feats;
+  double entropy = 0;
+  for (unsigned i = 0; i < cands_.size(); ++i) {
+    const double log_prob = cands_[i].fmap.dot(params) - log_z;
+    const double prob = exp(log_prob);
+    const double e_logprob = prob * log_prob;
+    entropy -= e_logprob;
+    if (g) {
+      (*g) += cands_[i].fmap * e_logprob;
+      exp_feats += cands_[i].fmap * prob;
+    }
+  }
+  if (g) (*g) += exp_feats * entropy;
+  return entropy;
+}
+
+}
+
diff --git a/training/entropy.h b/training/entropy.h
new file mode 100644
index 00000000..796589ca
--- /dev/null
+++ b/training/entropy.h
@@ -0,0 +1,22 @@
+#ifndef _CSENTROPY_H_
+#define _CSENTROPY_H_
+
+#include <vector>
+#include "sparse_vector.h"
+
+namespace training {
+  class CandidateSet;
+
+  class CandidateSetEntropy {
+   public:
+    explicit CandidateSetEntropy(const CandidateSet& cs) : cands_(cs) {}
+    // compute the entropy (expected log likelihood) of a CandidateSet
+    // (optional) the gradient of the entropy with respect to params
+    double operator()(const std::vector<double>& params,
+                      SparseVector<double>* g = NULL) const;
+   private:
+    const CandidateSet& cands_;
+  };
+};
+
+#endif
diff --git a/utils/fdict.h b/utils/fdict.h
index 71547d2e..eb853fb2 100644
--- a/utils/fdict.h
+++ b/utils/fdict.h
@@ -33,6 +33,8 @@ struct FD {
     assert(dict_.max() == 0);  // dictionary must not have
                                // been added to
     hash_ = new PerfectHashFunction(cmph_file);
+#else
+    (void) cmph_file;
 #endif
   }
   static inline int NumFeats() {